Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
 Pages:  1    3  ..  5
Author: Subject: Japanese nuclear reactor problems
Magpie
lab constructor
*****




Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline

Mood: Chemistry: the subtle science.

[*] posted on 12-3-2011 at 19:24
Japanese nuclear reactor problems


I've been watching CNN news on the damage in Japan due to the recent 8.9 earthquake and consequent tsunami.

I'm aghast at the technical descriptions of what is happening at the reactor(s). Only one person, a nuclear reactor expert at Yale I believe, has given a coherent and technically accurate description and answered questions accurately. One guy came on tonight with a nice diagram of the closed loops of a reactor and then botched it up with a hurried description of how it works, starting with the cooling water! If he would have slowed down and started with the fission process heat generation it would have been very informative.

Then Bill Nye, who claimed to be an engineer, was interviewed and claimed that cesium was a neutron absorber and part of the control rod! Now I'm totally disillusioned with the level of science understanding in the US. :(




The single most important condition for a successful synthesis is good mixing - Nicodem
View user's profile View All Posts By User
Sedit
International Hazard
*****




Posts: 1939
Registered: 23-11-2008
Member Is Offline

Mood: Manic Expressive

[*] posted on 12-3-2011 at 20:03


I seen the Bill Nye interview, or atlest one of them, and he never mentioned that. Infact he said if they are detecting Cesium then there is serious problems and its sure to get ALOT worse before it gets better seemingly shying away from mentioning it melting down.

There was however water and Boric acid being sprayed onto the reaction using the Boric acid as the Neutron absorber.... are you sure you did not just miss a section and misunderstand what you heard?

Im no nuclear chemist but I give it to Tuesday to either shut down or melt down. Thats my prediction and im sticking to it:D





Knowledge is useless to useless people...

"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story before."~Maynard James Keenan
View user's profile View All Posts By User
Magpie
lab constructor
*****




Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline

Mood: Chemistry: the subtle science.

[*] posted on 12-3-2011 at 20:28


Sedit I think you may have missed the first part of his interview - it was interrupted by the footage of a helicopter rescue. He did say "cesium". I will assume he confused this with "cadmium," which is a neutron absorber. He did then later say that if cesium is in the air there has been a breach, although he said breach of a "control rod" when he should have said a breach of a "fuel" assembly.

According to Wiki he is a mechanical engineer, so should have some knowledge of nuclear reactor design.




The single most important condition for a successful synthesis is good mixing - Nicodem
View user's profile View All Posts By User
Sedit
International Hazard
*****




Posts: 1939
Registered: 23-11-2008
Member Is Offline

Mood: Manic Expressive

[*] posted on 12-3-2011 at 20:45


I dunno, honestly I think there must have been two different interviews with him because he was on nothing of the sorts in the one I seen from start to finish.

He was more about the point that if they detected Cesium then there is no doubt its a bad deal.

Honestly I was more warped by the fact that The Science Guy... was a Mechanics Guy! Kind of confused me a bit and from his posture in the interview I think it confused him to. I would not credit him as a reliable source.





Knowledge is useless to useless people...

"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story before."~Maynard James Keenan
View user's profile View All Posts By User
anotheronebitesthedust
Hazard to Others
***




Posts: 189
Registered: 24-6-2007
Member Is Offline

Mood: No Mood

[*] posted on 12-3-2011 at 20:51


http://www.youtube.com/watch?v=af-41E5mndk
View user's profile View All Posts By User
leu
National Hazard
****




Posts: 368
Registered: 13-10-2005
Member Is Offline

Mood: No Mood

[*] posted on 13-3-2011 at 14:02


Some relevant links:

http://www.iaea.org/newscenter/news/tsunamiupdate01.html

http://www.mirror.co.uk/news/top-stories/2011/03/13/sea-wate...

http://news.sky.com/skynews/Home/World-News/Video-Fukushima-...

http://www.nisa.meti.go.jp/english/

http://www.iaea.org/Publications/Factsheets/English/ines.pdf

http://www.cnn.com/2011/WORLD/asiapcf/03/12/japan.quake.nucl...

http://www.washingtonpost.com/wp-dyn/content/article/2011/03...

:cool:





Chemistry is our Covalent Bond
View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 14-3-2011 at 11:15


It has not been my desire to increase the despair or hysteria during a time when that is not helpful to people who are counting their uncountable dead and at the same time fighting for their lives in the midst of a disaster .....however ....
to be entirely realistic and cut through the b.s. of positive spin or minimizing ....
the magnitude of this catastrophe is huge and growing ......and the loss of life already as well as that potential for increasing exponentially should be acknowledged as significantly greater than what has been reported via
a likely "toned down" reporting which has been done for respect of the sensitive nature of a story about such a catastrophe. Putting aside that decorum of optimism and "sensitivity" which avoids frankly describing the circumstances .......
Japan is in some very deep shit already which is deep shit getting deeper by the hour. The worst is probably not over nor even beginning to be over at this juncture and the ultimate losses of life as well as property may be profound
beyond what the carefully limited publication of reporting has thus far described.
View user's profile View All Posts By User
unionised
International Hazard
*****




Posts: 4935
Registered: 1-11-2003
Location: UK
Member Is Offline

Mood: No Mood

[*] posted on 14-3-2011 at 12:56


Do you have any evidence for that?
View user's profile View All Posts By User
Lambda-Eyde
International Hazard
*****




Posts: 856
Registered: 20-11-2008
Location: Norway
Member Is Offline

Mood: Cleaved

[*] posted on 14-3-2011 at 13:11


Recommended read: http://theenergycollective.com/barrybrook/53461/fukushima-nu...
View user's profile View All Posts By User
Twospoons
International Hazard
*****




Posts: 1192
Registered: 26-7-2004
Location: Middle Earth
Member Is Offline

Mood: A trace of hope...

[*] posted on 14-3-2011 at 13:51


Thanks for that - a very interesting read.



Helicopter: "helico" -> spiral, "pter" -> with wings
View user's profile View All Posts By User
madscientist
International Hazard
*****




Posts: 962
Registered: 19-5-2002
Location: American Midwest
Member Is Offline

Mood: pyrophoric

[*] posted on 14-3-2011 at 17:01


"Don't worry, the situation is under control," they said. Kaboom. "Oh, not much radiation leaking," they said. Then the US military (which sprays DU everywhere without concern for the hazards) repositioned an aircraft carrier out of the fallout zone.

They've cut corners (failed to waterproof the backup generators?!), lied about inspections, and keep saying "a certain bad something probably won't happen" right before it happens. I'm not seeing much reason to believe a single word they say.

Famous last words of a chemist: "Trust me, this is a perfectly safe setup. I know exactly what I am doing."

Famous last words of a nuclear engineer: "Trust me, this is a perfectly safe reactor, unlike the others that came before. This time, we have overlooked nothing."

Pride comes before the fall! Don't put too much faith in our engineering. We lie, cut corners, and make mistakes - I'd rather the consequences didn't involve waiting for geological processes to bury fallout, or the rise of a benign Godzilla.

What a disaster.




I weep at the sight of flaming acetic anhydride.
View user's profile View All Posts By User
ScienceHideout
National Hazard
****




Posts: 391
Registered: 12-3-2011
Location: In the Source
Member Is Offline

Mood: High Spin

[*] posted on 14-3-2011 at 17:33


My favorite power? Nuclear power!

Don't blame all nuclear powerplants, don't blame the earthquake, blame yourself living next to a nuclear power plant. And in the case that I exer live near a nuclear plant, in a meltdown, at least I'll die being near the place I love.

I know... I know. That's just my opinion. Nuclear power is green, efficient, and they really never blow up like that. Who would build a reactor on a FAULT LINE???? I know. I do feel sorry for the Japanese, but no one, not even the engineer, can control earthquakes.




hey, if you are reading this, I can't U2U, but you are always welcome to send me an email!


View user's profile Visit user's homepage View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 14-3-2011 at 19:08


Quote: Originally posted by unionised  
Do you have any evidence for that?


(Pontius) Pilate answered, "quod scripsi, scripsi"
(What I have written, I have written)

Luke: "Are you all right? What's wrong?" Obi-Wan: "I felt a great disturbance in the Force... as if millions of voices suddenly cried out in terror and were suddenly silenced. I fear something terrible has happened. You'd better get on with your exercises."


Quote: Originally posted by madscientist  
"Don't worry, the situation is under control," they said.

[snip]

Pride comes before the fall! Don't put too much faith in our engineering. We lie, cut corners, and make mistakes - I'd rather the consequences didn't involve waiting for geological processes to bury fallout, or the rise of a benign Godzilla.

What a disaster.


YGTFR! And it is a logistical nightmare for responders. It is a catastrophe of cataclysmic dimensions that are not truly yet realized...... it is simply not immediately comprehensible, because the shock of the spectacle has overwhelmed objective analysis.
View user's profile View All Posts By User
Sedit
International Hazard
*****




Posts: 1939
Registered: 23-11-2008
Member Is Offline

Mood: Manic Expressive

[*] posted on 14-3-2011 at 19:58


Fires breaking out so I can't see them cooling the reactor to efficiently when thats happening. I guess they put it out though but are still saying more radiation was leaked meaning the fire couldn't have been far from the core I would assume.

http://www.aolnews.com/2011/03/14/explosion-heard-at-japan-n...


I would like to believe they would have it contained by tommorow but I just don't see resolution of anykind that fast as it appears to still be esculating.

I feel a melt down is imminant even if the reactor is strong enough to contain it as the documents posted by Lambda seem to suggest. I question that documents talk about this just being residual heat. If so why after being cooled for along time with water it heated back up when they where forced to stop for a little bit melting one of the rods. When an object is just hot with radiant heat and cooled with water it should not quickly shoot back up in 45 minutes to over 3000degrees C if the cooling is stopped.





Knowledge is useless to useless people...

"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story before."~Maynard James Keenan
View user's profile View All Posts By User
hkparker
International Hazard
*****




Posts: 601
Registered: 15-10-2010
Location: California, United States
Member Is Offline

Mood: No Mood

[*] posted on 14-3-2011 at 20:57


Periodicvideos did a video on this recently, good explanation:

http://www.youtube.com/watch?v=-bcrLiATLq0




My YouTube Channel

"Nothing is too wonderful to be true if it be consistent with the laws of nature." -Michael Faraday
View user's profile Visit user's homepage View All Posts By User
Twospoons
International Hazard
*****




Posts: 1192
Registered: 26-7-2004
Location: Middle Earth
Member Is Offline

Mood: A trace of hope...

[*] posted on 14-3-2011 at 21:00


This was explained in the document - the continued heating comes from the decay of the iodine and caesium fission products. I guess the heating rate would depend on how old the fuel rods were, ie how much I and Cs were in the rods. I read somewhere else that spent fuel rods have to be stored in water to prevent heat build up.



Helicopter: "helico" -> spiral, "pter" -> with wings
View user's profile View All Posts By User
Magpie
lab constructor
*****




Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline

Mood: Chemistry: the subtle science.

[*] posted on 14-3-2011 at 22:55


Quote: Originally posted by Twospoons  
This was explained in the document - the continued heating comes from the decay of the iodine and caesium fission products. snip


There's more than just cesium-137 and iodine-131 fission products producing heat. From Wiki:

"The radioactivity in the fission product mixture is mostly due to short lived isotopes such as I-131 and 140Ba, after about four months 141Ce, 95Zr/95Nb and 89Sr take the largest share, while after about two or three years the largest share is taken by 144Ce/144Pr, 106Ru/106Rh and 147Pm. Later 90Sr and 137Cs are the main radioisotopes, being succeeded by 99Tc. In the case of a release of radioactivity from a power reactor or used fuel, only some elements are released; as a result, the isotopic signature of the radioactivity is very different from an open air nuclear detonation, where all the fission products are dispersed."




The single most important condition for a successful synthesis is good mixing - Nicodem
View user's profile View All Posts By User
watson.fawkes
International Hazard
*****




Posts: 2793
Registered: 16-8-2008
Member Is Offline

Mood: No Mood

[*] posted on 15-3-2011 at 04:24


Quote: Originally posted by Lambda-Eyde  
Recommended read: http://theenergycollective.com/barrybrook/53461/fukushima-nu...
Here's the author's bio page at MIT: Oehmen, Josef - Lean Advancement Initiative. LAI is an academic management consultancy institute. Here's what the author does there: (quotations both taken from that page)
Quote:
The main research interest of Dr. Josef Oehmen is risk management in the value chain, with a special focus on lean product development
The damage control has already begun:
Quote:
Josef is the author of the essay “Why I’m not worried about Japan’s nuclear reactors”. It was an email he sent to his family in Japan. When his cousin posted it on his blog, it went viral. Josef is working hard with a team from MIT to provide an appropriate response to the interest the post has generated. The original blog will be migrated to an MIT site, managed by a team of experts from MIT's Department of Nuclear Science and Engineering. The link will be posted here when it becomes available. Josef is not a nuclear scientist or engineer. He is a mechanical engineer by training, working on product development processes with MIT's Lean Advancement Initiative and the MIT-KFUPM Center for Clean Water and Energy.
This incident illustrates one of the main problems with nuclear energy in practice, as opposed to principle: blind cheerleading. The guy is parroting things he's heard from other people. It does not constitute independent analysis. In the sense, it's bullshit, in exactly the sense expounded by Harry G. Frankfurt in his excellent essay On Bullshit: statements made without particular regard for their actual truth. He's trusting engineers without his own analysis, which he might be capable of, but doesn't show any evidence of. And, of course, events have already proven him wrong. In witness, here's the second paragraph of his piece:
Quote:
There was and will *not* be any significant release of radioactivity.
Yeah, right.

The blind cheerleading doesn't stop with him. It includes everybody who's uncritically quoted it because it argues a "pro" position with respect to nuclear power. Caricature: "He's got a PhD, he must be right!" This factionalism is, it needs reminding, antithetical to a scientific approach to the whole issue, a public issue that is in desperate need of more actual science in public discourse.

View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 15-3-2011 at 04:55


This is simply an unconfirmed piece of information which I heard over the radio during a talk show broadcast ....where someone mentioned that the GPS data
was showing that following the earthquake that the entire island had been moved about 8 feet from its previous location and that the axis of rotation for
the entire earth had been shifted 10 inches ......which provides a clue as to what magnitude of force was felt by Japan. Additionally there have been permanent
changes in terrain elevation of 6 feet which has effectively also changed the location of the coastline by several miles resulting in what was waterfront property before now and hereafter being located on the sea bottom several miles out to sea from the new shoreline.

Thousands of bodies have been washing ashore on the tide, and there is a shortage of body bags. Corpses are being burned unceremoniously because
the regular funeral crematoriums are overwhelmed beyond capacity.
View user's profile View All Posts By User
Regolith
Hazard to Self
**




Posts: 73
Registered: 4-2-2011
Location: Mining the moon.
Member Is Offline

Mood: Glacial

[*] posted on 15-3-2011 at 05:24


Damn, I leave for a week to make sure friends and family in Japan are alive and the board opens one of my favourite topics, Nuclear Power.

Reactors 1, 2 and 3 at the Fukushima plant are in meltdown in one form or another. The cores of each have had parts of them exposed to the air which they aren't meant todo for any amount of time, at least not immediately following active service.

Following hydrogen explosions and the destruction of the outside biological shield. Which was mostly for protection from the elements and never truly designed to contain fission products. The reactors have almost no support machinery available to them even if power was restored. At this point all of the reactors have been technically destroyed. Each of them is now functioning in the last ditch emergency failure mode. None of them will be able to be recovered and used again. They will need to be decommissioned. Unlike chernobyl however, which was a total meltdown followed by possibly a kiloton grade nuclear explosion within the core. These cores will be removable and will be able to be disposed of in a safe manner. The reactor vessels themselves are able to contain 5000F degree heat this is beyond the maximum generation temperature available to the nuclear fuel. In addition the nuclear cores aren't critical currently they have shut down the heat is all residual generated by decay of fission products. Again unlike chernobyl which was fully active when exposed to the environment.

They did learn from mistakes of the past when they made these. We didn't know earthquakes could get that big when they built the plant. The generator for backup was in a well shielded shed that was washed away by a massive wave. This facility was made to handle quakes a 1000 times less powerful than what hit. That it's doing as well as it is.. It's amazing

The reactors in full meltdown are going to be much harder to cool as a giant lump, of semi-molten nuclear fuel. Has far less surface area than small rods so they are still struggling to keep them as cool as possible.The highest radiation levels measured so far are approx 8 times the normal background radiation, these were detected during the emergency venting. Again a huge difference between this and previous disasters is the amount of monitoring. The american carrier just off the coast has sophisticated monitoring equipment and moved incase of a wind shift and to have their rescue aircraft not transit the reactor area. Exposure so far has been effectively dealt with by washing with simple soap and water. They have detection equipment everywhere and the safety zone around the reactor has been emptied. As nuclear disasters go, this is so far going very well.
View user's profile View All Posts By User
entropy51
Gone, but not forgotten
*****




Posts: 1612
Registered: 30-5-2009
Member Is Offline

Mood: Fissile

[*] posted on 15-3-2011 at 08:45


Quote: Originally posted by Regolith  
Unlike chernobyl however, which was a total meltdown followed by possibly a kiloton grade nuclear explosion within the core.
The energy release at Chernobyl was about one ton of TNT, nowhere near 1000 tons.

[Edited on 15-3-2011 by entropy51]
View user's profile View All Posts By User
bquirky
National Hazard
****




Posts: 316
Registered: 22-10-2008
Location: Perth Western Australia
Member Is Offline

Mood: No Mood

[*] posted on 15-3-2011 at 09:11


this is probobly a dumb question


but at present what is the limiting factor preventing further cooling ?

is it simply that they cant pump enough water through it ?
is there a point where pumping more water doesn't help ?

is there some kind of hidden 'cost' to pumping huge volumes of water in (like what to do with it when it comes out) ?


View user's profile View All Posts By User
Saerynide
International Hazard
*****




Posts: 954
Registered: 17-11-2003
Location: The Void
Member Is Offline

Mood: Ionic

[*] posted on 15-3-2011 at 11:20


I would assume the limiting factor is if the rate of water boiling off is greater than the rate that water can be put in, or maybe so much heat is being generated that the water cant even boil off fast enough to remove it at an equal rate?

I read that 30 tons of water boils off each reactor per hour... thats a shitton of water (and energy) :o Keeping up with a flow rate of 500 L/min is impressive.

[Edited on 3/15/2011 by Saerynide]




"Microsoft reserves the right at all times to monitor communications on the Service and disclose any information Microsoft deems necessary to... satisfy any applicable law, regulation or legal process"
View user's profile View All Posts By User
madscientist
International Hazard
*****




Posts: 962
Registered: 19-5-2002
Location: American Midwest
Member Is Offline

Mood: pyrophoric

[*] posted on 15-3-2011 at 11:35


And although as time goes on, the material becomes less fissile, the surface area decreases as the rods melt into a blob. Doesn't bode well for cooling.



I weep at the sight of flaming acetic anhydride.
View user's profile View All Posts By User
entropy51
Gone, but not forgotten
*****




Posts: 1612
Registered: 30-5-2009
Member Is Offline

Mood: Fissile

[*] posted on 15-3-2011 at 11:47


Quote: Originally posted by bquirky  
but at present what is the limiting factor preventing further cooling ?

is it simply that they cant pump enough water through it ?
is there a point where pumping more water doesn't help ?
One of many problems is buildup of pressure within the reactor vessel due to the steam produced when the injected water contacts the over-heated fuel rods and boils. If the fuel is uncovered and the temperature exceeds 2200 F, the steam reacts with the zirconium cladding on the fuel to produce hydrogen, which raises the pressure even more. As the pressure increases it becomes difficult to pump in large volumes of water and the fuel rods are blanketed by a huge bubble of steam and hydrogen. When the vessel is vented to remove the steam to the atmosphere it causes two problems: 1. The steam carries radioactive contaminants from the damaged fuel and 2. the hydrogen can explode, as has happened three times now, severely damaging the reactor building.
View user's profile View All Posts By User
 Pages:  1    3  ..  5

  Go To Top