Possible reactor meltdown in Japan

[PandaBear]

Is it possible to run filter through the water to reduce the contamination while keeping it cool? This is probably not going to be a permanent solution but at least reduce the runoff while keeping the reactor core enough till later, so we can entomb it properly without worrying about ground water leak and contamination.

 

[ToyotaNSaturn]

That still-in-Illinois but looking-at-Indiana company?

 

[Volvo_ST1]

Originally Posted By: PandaBear
Is it possible to run filter through the water to reduce the contamination while keeping it cool?


I suppose you want run the water through a filter, not the other way around. The H in the H2O has been epxosed to ionizing radiation. The H itself will emit radiation, and you can't filter it at all.

Then there are the radioactive particles. How small are they? How much water do you have to filter? How long does that take? Who and how will people even install the filters? Do such filters exist?

Quote:
This is probably not going to be a permanent solution but at least reduce the runoff

How does filtering contaminated water reduce the runoff? They don't even know where the runoff is coming from at this time.

Quote:
while keeping the reactor core enough till later,

Eh? The core may well breach the containment vessel. I suppose that's when Mystic's brilliant suggestion of pouring concrete under the facility will come into play.

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so we can entomb it properly without worrying about ground water leak and contamination.


"We?" They will not be able to prevent groundwater contamination by entombing the plant. The proverbial genie is peeking out of the bottle. Contamination is in the groundwater, it's in the air and on the soil, it's in the ocean. The question is how much more of the genie will escape. Whatever has gotten out is out. The whole bleeping genie may come out.

 

[Al]

Originally Posted By: PandaBear
Is it possible to run filter through the water to reduce the contamination while keeping it cool? This is probably not going to be a permanent solution but at least reduce the runoff while keeping the reactor core enough till later, so we can entomb it properly without worrying about ground water leak and contamination.

You are talking massive, massive equipment/pumps/controls etc. Filters clog up and require sophisticated ways of cleaning/regenerating. Given unlimited time, resources, and an environment that is possible to work in you suggestion could be done. But again we are talking millions of curies in an environment that is not possible to work in. Its not possible to do what you are suggesting.

You will see in the coming days/weeks what I am talking about.

Originally Posted By: Volvo_ST1

Then there are the radioactive particles. How small are they? How much water do you have to filter? How long does that take? Who and how will people even install the filters? Do such filters exist?

You have the basic idea.

 

[LS2JSTS]

Al or Mola or Astro...can you tell me something?

I know that concrete melts or burns at a pretty low temperature, at least a temperature well below what can be found inside that containment vessel. So, how does the thing get entombed until those temperatures drop quite a bit, and how do they do that?

If they just let it sit, how long would it take for the temps to drop enough to allow the concrete to set up? Any idea what kind of mix that would be, I'm sure it's not the typical "6 bag" mix found around here.

Also, any idea what the actual burn/melt point would be for the concrete that already surrounds the containment vessel?

I heard that if we start to see lots of white smoke, not steam but white smoke. Then that is a sign that the crete, and by extension, the containment vessel, has been breached, any truth to that? The theory being that concrete burns white when at temperature. Something about the calcium...IDK.

TIA

 

[OVERKILL]

Originally Posted By: LS2JSTS
Al or Mola or Astro...can you tell me something?

I know that concrete melts or burns at a pretty low temperature, at least a temperature well below what can be found inside that containment vessel. So, how does the thing get entombed until those temperatures drop quite a bit, and how do they do that?

If they just let it sit, how long would it take for the temps to drop enough to allow the concrete to set up? Any idea what kind of mix that would be, I'm sure it's not the typical "6 bag" mix found around here.

Also, any idea what the actual burn/melt point would be for the concrete that already surrounds the containment vessel?

I heard that if we start to see lots of white smoke, not steam but white smoke. Then that is a sign that the crete, and by extension, the containment vessel, has been breached, any truth to that? The theory being that concrete burns white when at temperature. Something about the calcium...IDK.

TIA


We've been seeing white smoke for quite some time.....

 

[LS2JSTS]

Any video to share or sources for info?

All the smoke I've seen has been either darker, like in the Hydrogen explosions or steam that dissipates quickly. I haven't seen any heavy white smoke....but I haven't been following real close.

 

[OVERKILL]

Originally Posted By: LS2JSTS
Any video to share or sources for info?

All the smoke I've seen has been either darker, like in the Hydrogen explosions or steam that dissipates quickly. I haven't seen any heavy white smoke....but I haven't been following real close.


http://www.guardian.co.uk/world/gallery/...16&index=24

One of them was/is smoking pretty much constantly for quite some time.

 

[Al]

Originally Posted By: Al

The biggest problem is how to keep the core cool going forward..without contamination of the water used to cool it. It needs to have a self contained cooling system to operate for 1 to two years at least.

Hate to say I told you so on the 12th

http://www.cnn.com/2011/WORLD/asiapcf/03/29/japan.nuclear.reactors/index.html?hpt=T2

"TEPCO is in an awful dilemma right now," said Jim Walsh, an international security expert at the Massachusetts Institute of Technology. "One the one hand, they want to cool the reactor and keep the reactor cool, so they have to pour water in. If there is a leak in one of the containment vessels, that water keeps leaking out. So they have a problem where the more they try to cool it down, the greater the radiation hazard as that water leaks out from the plant."

They will need to make a decision as to whether to keep cooling it or not.

 

[Blaze]

I noticed in one of thier control rooms it appears ceiling panels or something of that nature have broken loose and are dangling... I wonder if that was caused from the explosions?

 

[Astro14]

Originally Posted By: LS2JSTS
Al or Mola or Astro...can you tell me something?

I know that concrete melts or burns at a pretty low temperature, at least a temperature well below what can be found inside that containment vessel. So, how does the thing get entombed until those temperatures drop quite a bit, and how do they do that?

If they just let it sit, how long would it take for the temps to drop enough to allow the concrete to set up? Any idea what kind of mix that would be, I'm sure it's not the typical "6 bag" mix found around here.

Also, any idea what the actual burn/melt point would be for the concrete that already surrounds the containment vessel?

I heard that if we start to see lots of white smoke, not steam but white smoke. Then that is a sign that the crete, and by extension, the containment vessel, has been breached, any truth to that? The theory being that concrete burns white when at temperature. Something about the calcium...IDK.

TIA


Pretty technical questions...well outside my ability to answer in any detail. I know that the zirconium alloy around the rods starts to melt at about 2,000C - that's when you will start to see Zirconium in the atmosphere. The MOX melts about 1000C higher - that's when you'll see the U235/238 and P239 in the atmosphere...Decay heat takes a long time to go down...and since the reactors were running when they were shut down, there is a LOT of decay heat...7% of the full output at first...so we're talking megawatts of heat to be cooled for the next several months to several years...So, I don't know if concrete will contain it...it has to be cooled for a while, then entombed...

Color of smoke is interesting, but not definitive or conclusive by any means...

But they need to be cooled, or the fuel rod cladding melts and the Uranium and Plutonim (among others) are exposed. Keep 'em cool, and they stay contained. If the rods are already compromised, then you have a containment issue, but you still need to cool it to prevent further compromise...

 

[Al]

I think they are getting close to stop cooling. The water is running over exposed fuel and spreading it everywhere. Also the water is not being circulated so steam is taking the stuff into the air.

It may be that stopping to cool it ... it will form into a molten glass ball and stop spreading.

Decay heat in even the operating reactor is below .2%

 

[Shannow]

Concrete won't burn as such...the heat drives the carbonate back into gaseous form, and it decomposes, basically falling apart.

 

[LS2JSTS]

Wasn't sure how to describe it...burn/melt...lol.

So, do you know what color the gas would be when this happened. Would it be white and would it linger in the air, or dissipate quickly?

 

[LS2JSTS]

Originally Posted By: Al
...

Decay heat in even the operating reactor is below .2%


@ what temperature would that be?

 

[Al]

Originally Posted By: LS2JSTS
Originally Posted By: Al
...

Decay heat in even the operating reactor is below .2%


@ what temperature would that be?
Its not a function of temperature. Its a function of time. You could take the fuel and freeze it but it keeps producing that .2% decay heat. It will then heat up and stop getting hotter as long as the .2% decay heat = heat being rejected. If you reject less the temp will go up to a point where it reaches equilibrium again. But it still continues giving off decay heat.









l

 

[ToyotaNSaturn]

the Guardian: Lost the race to save the reactor?

 

[Astro14]

Originally Posted By: Al
Decay heat in even the operating reactor is below .2%


Doesn't that depend on the reactor design? (...including the fuel mix)...still, even at .2% of hundreds of megawatts...those rods will continue to heat unless there is something to remove (reject) the heat...and over hours, then days, then weeks, that heat builds...

 

[Al]

Originally Posted By: Astro14
Originally Posted By: Al
Decay heat in even the operating reactor is below .2%


Doesn't that depend on the reactor design? (...including the fuel mix)...still, even at .2% of hundreds of megawatts...those rods will continue to heat unless there is something to remove (reject) the heat...and over hours, then days, then weeks, that heat builds...

It depends as you probably know on the total amount of full power days and the enrichment. The lower the enrichment the more decay heat. That's why highly enriched navy reactors have very little decay heat.

If their reactor is like 1700 thermal megawatts that's like 3.5 MW/core. I'm not a nuclear physicist..just information I picked up, but have to go on the internets to remember.

 

[OVERKILL]

Originally Posted By: ToyotaNSaturn
the Guardian: Lost the race to save the reactor?


Just read that

Quote:
Workers at the crippled Fukushima Dai-ichi nuclear plant appeared to have "lost the race" to save one of the reactors, a U.S. expert told the Guardian.
Richard Lahey, who was head of safety research for boiling water reactors at General Electric when the company installed the units at the Japan plant, says the radioactive core in the Unit 2 reactor appears to have melted through the bottom of its containment vessel and on a concrete floor.
"The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell," Lahey told the paper.


Read more: http://www.foxnews.com/world/2011/03/29/.../#ixzz1I2Qw4AnG