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Sheetal.Pandey
Oh if the tragedy extends to nuclear reactors, it would be beyond controllable. ...
Frank Eory
The U.S. media has recently discovered and reported that we have over 65,000 ...
Fuel rod reactions stoke nuclear tensions
R Colin Johnson
3/17/2011 12:07 AM EDT
Nuclear reactions starting
By Wednesday morning Japan time, the BBC confirmed that a "criticality event" was being reported in the No. 4 fuel pond after it caught fire. The fire was initially thought to have been extinguished, but then reignited. Tokyo Electric Power, which has come in for intense criticism for failing to keep government officials informed on the condition of the Fukushima reactors, has now admitted that "criticality" was reached during the first fire, and, according to reports, “The possibility of re-criticality is not zero."
"The explosion at the spent fuel pond at reactor No. 4 was a criticality explosion," Moglen asserted, "which means that the fuel in that pond has begun to interact on a nuclear level--that there was a nuclear chain reaction going on in the pond."
A "criticality event" means that the melted fuel rods accumulated enough mass to exceed the "critical" stage and start a nuclear chain reaction similar to the controlled reaction in a normal reactor. Without a containment vessel, the nuclear reaction emits large amounts of radiation while potentially releasing radioactive particulate directly into the air.
"The spent fuel ponds are even more dangerous than the inside of the reactors because the fuel pools are open to the air. At least there is a containment vessel around the reactor cores," said Moglen. "All six pools are in jeopardy, since they need to be constantly supplied with water to replace that which the fuel rods are constantly boiling off."
So far, nuclear reactions have only been reported in the No. 4 reactor fuel pond, but Tokyo Electric Power said fuel pools in the Nos. 5 and 6 reactors are becoming superheated, and that the No. 3 fuel pool is on fire.
"It’s like a cascade event, resulting in crisis after crisis without being able to resolve any of them," Moglen said.
To watch and hear experts discuss Japan's nuclear crisis, please visit this page on EE Life.
By Wednesday morning Japan time, the BBC confirmed that a "criticality event" was being reported in the No. 4 fuel pond after it caught fire. The fire was initially thought to have been extinguished, but then reignited. Tokyo Electric Power, which has come in for intense criticism for failing to keep government officials informed on the condition of the Fukushima reactors, has now admitted that "criticality" was reached during the first fire, and, according to reports, “The possibility of re-criticality is not zero."
"The explosion at the spent fuel pond at reactor No. 4 was a criticality explosion," Moglen asserted, "which means that the fuel in that pond has begun to interact on a nuclear level--that there was a nuclear chain reaction going on in the pond."
A "criticality event" means that the melted fuel rods accumulated enough mass to exceed the "critical" stage and start a nuclear chain reaction similar to the controlled reaction in a normal reactor. Without a containment vessel, the nuclear reaction emits large amounts of radiation while potentially releasing radioactive particulate directly into the air.
"The spent fuel ponds are even more dangerous than the inside of the reactors because the fuel pools are open to the air. At least there is a containment vessel around the reactor cores," said Moglen. "All six pools are in jeopardy, since they need to be constantly supplied with water to replace that which the fuel rods are constantly boiling off."
So far, nuclear reactions have only been reported in the No. 4 reactor fuel pond, but Tokyo Electric Power said fuel pools in the Nos. 5 and 6 reactors are becoming superheated, and that the No. 3 fuel pool is on fire.
"It’s like a cascade event, resulting in crisis after crisis without being able to resolve any of them," Moglen said.
To watch and hear experts discuss Japan's nuclear crisis, please visit this page on EE Life.
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ee-joe
3/17/2011 5:16 PM EDT
There is always a risk from any technology used to produce energy. People are allways ready to abandon something because of an accident. Why don't we abandon cars, they kill people every year. Stop traveling, plane and train accidents kill people every year. We as a society need to get away from thinking about perfection. As long as people are involved in the design and manufacture of anything, perfection is a pipe dream. We need to learn from our mistakes, or in this case the wrath of mother nature, suck it up and move on. We waste too much time and energy dwelling in the past.
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jron
3/17/2011 8:00 PM EDT
ee-joe,
I think your response is rather blithe.
If each car accident caused increased cancer deaths and genetic defects of thousands of people, radiation deaths of hundreds of others, global radiation pollution, I might begin to agree with you, but, of course, I do not.
The scale of this disaster, its negative global effects, including damaging genetic effects to lifeforms everywhere on the planet, make this entirely different risks than cars, trains and automobiles! Yes, people die from all of them, but only radiation can mutate the germlines of all living creatures, and kill thousands, if not millions of people.
ee-joe, please use more logic in your risk assessments, they are nonsensical!
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qerqwe
3/17/2011 8:03 PM EDT
The problem is not the fact SH*T happens. It is the scale. I think this is the biggest problem with Nuclear power, the plants are just way to big. If there were 10-20 smaller plants scatter around instead of the 6 LARGE plant located in one place. This 'accident' could have been more easily contained. If you do scatter plants, it does mean more accidents, but less severe.
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tb1
3/17/2011 7:19 PM EDT
ee-joe, there are accidents, and then there are accidents.
(I certainly hope you aren't driving around in a plutonium powered car.)
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Frank Eory
3/18/2011 3:26 AM EDT
"there are accidents, and then there are accidents." True, but there are benefits too.
The lesson to be learned from this is not that nuclear power is unacceptably risky, but that nuclear power must be made safer -- as safe as modern technology and understanding can make it.
Consider the age of many of the world's nuclear power plants. The Fukushima reactors, for example, were commissioned in the '70s and were based on designs from the '60s. Even the old-timers here on EE Times were children when these things were designed, and probably most EE Times readers weren't even born yet.
Think about that in terms of the evolution in science & technology in the last half-century. Knowledge and understanding of nuclear physics, seismology, climatology, and of course the capabilities of electronic sensors, control systems and computing power have advanced by leaps and bounds over the course of time -- all of which means that today we could produce not only much better designs, but we could design them to much better specs.
But to do that, there would need to be business incentives and governmental support (or at least not opposition) for modern nuclear power technology, which has been sorely lacking for most of the last half century -- at least in the U.S.
Despite the substantial percentage of total electricity generated by nuclear power in industrialized countries, the nuclear power industry has for decades been the unwanted stepchild that is uncomfortably tolerated, with the public just wishfully hoping it would eventually fade away or choosing just to not think about it very much.
And now we are paying the price for allowing such an important and hazardous technology to atrophy rather than to advance and modernize.
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daveb
3/18/2011 3:53 PM EDT
I just read that the reactor was scheduled for decommissioning next month... Rats!
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FERGUS
3/17/2011 9:37 PM EDT
THE IDEA THAT PLUTONIUM IS EXQUISITELY TOXIC IS COMPLETE NONSENSE. THERE WERE TWO STUDIES AROUND 1997 THAT SHOWED IT TO BE LESS TOXIC THAN NICOTINE. IN ONE CASE, PLUTONIUM CITRATE WAS INJECTED INTRAVENOUSLY. IN THE OTHER, IT WAS SWALLOWED. THE PEOPLE THAT CAME UP WITH THE TOXICITY CLAIM HAD NO EVIDENCE AT ALL.
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pkg
3/17/2011 9:54 PM EDT
I'm a Christian, and this sounds ridiculous to me as well. If I was so inclined to make some sort of biblical reference to this event (and I'm not) I think I could come up with a better fit than this. I suspect the original posting may be from a "troll" just trying to see what kind of reaction he can get.
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tb1
3/17/2011 11:13 PM EDT
I Googled Plutonium Citrate and the only thing that came up were rat studies that induced cancers in all the rats.
Also, pure nicotine is highly poisonous. In fact, it is sold as a rat poison.
Of course, considering the post was in all capitals, I should have been forewarned.
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pshakii
3/18/2011 12:50 AM EDT
I believe there are lot of knee-jerk reactions happening around the world due to this issue.
Main issue with nuclear energy is "long term effects on the environment and people if there is a real disaster" and also another main concern safe storage of spent fuel.
Hence basic question is not only how safe these reactors are but how well we are prepared if there a nuclear accident? We are very small infront of mother nature and I am sure in future nuclear accidents are bound to happen.
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kdboyce
3/18/2011 2:46 AM EDT
Regardless of the beliefs underlying the comments so far, there is no excuse for the language being used and is not something I want to see in the posts and is not worthy of EETimes to allow. As engineers we need to focus on verifiable facts and use our power to correctly educate and inform so that the best decisions can be made by us all.
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Darren1022
3/18/2011 5:35 AM EDT
I personally do not condone the Japanese whaling activities. However, in saying that, nor I do believe an earthquake is of direct consequence of such.
Here in New Zealand, we're on the forefront of anti-whaling activities. Then explain it to me scientifically:
Why an anti-whaling country such as New Zealand had a 7.4 magnitude earthquake last September in the Canterbury region shortly after a public clash with Japanese whalers and a 6.4 aftershock 3 weeks ago in which lives were claimed?
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kdboyce
3/19/2011 1:07 AM EDT
Darren,
I for one appreciate the apology re language use. I wish you and your family well in the present circumstances and hope that they come to no harm.
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Darren1022
3/19/2011 1:42 AM EDT
@kdboyce
Thank you and I really appreciate it.
My mother contacted me this morning and informed me that she is no longer within the radiation zone. And there was very minimal trace of radiation on her. Unfortunately she did lose her house in Chiba to the tsunami. But buildings can be replaced, I am just glad that she's safe.
Thank you again.
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prabhakar_deosthali
3/18/2011 7:43 AM EDT
Looks like our emotions have taken us back some thousand years back and we seem to have forgotten our objective approach to look at the disaster and its consequences. As recently has been discovered this world is so huge ( the recent discovery tells us that there are stars in this universe which are some billion light years away from us). In such cosmic scale the Japanese earthquake is something so minuscule in proportion that the GOD almighty of whatever religion it may be , may not have even noticed that such a thing has happened. Mankind's progress has happened by learning from such accidents, such natural disasters. While we rue the losses and worry about the consequences of such disasters we also make corrections in our future designs to avoid recurrences of such events. Because we are there to survive! We humans are there to survive! We engineers are there to make new inventions and new discoveries. Like a spider we are going to rebuild our nets every time it gets destroyed. With each disaster we are going to be wiser and smarter.
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paboyle
3/18/2011 11:48 AM EDT
Moglen asserts there has been a criticality
even at reactor 4, citing the BBC article.
This is NOT what the BBC article says.
Friends of the Earth should not, go around making up plausible lies sensationalising these terrible events.
The BBC article says TEPCO raised the possibility of a recriticality event in the future. It does not state that the fire at reactor 4 had anything to do with the pool having already gone critical.
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przemek
3/18/2011 4:49 PM EDT
Darren: +1
ubm...: -1
It's not possible to have a rational argument with an irrational person. They will drag you down and beat you with experience.
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David Ashton
3/19/2011 6:18 AM EDT
I'd tend to agree. I don't condone Darren's use of language in this forum, but I do understand the reasons for his emotions, and he has apologised. Darren, I too wish you and yours well.
UBM on the other hand has consistently refused to give logical answers to questions of his theories (I use the word loosely here). In spite of specific requests he has not stated why god has punished Japan for whaling but also apparently punished NZ for it's anti-whaling stance. If I've got you wrong, UBM, please explain further, but please for heaven's sake try to do so logically.
UBM, if your god is responsible for all these natural disasters, he must be a pretty twisted, vengeful, spiteful and indiscriminate god. I believe pretty loosely in a higher power, but I don't see him as being like that.
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David Ashton
3/19/2011 10:39 PM EDT
The comment above was correct:
"It's not possible to have a rational argument with an irrational person"
Until you can answer the questions I posed above, I will take it that you cannot do so. Calling my questions stupid does not help. The only stupid question is one that is not asked, and clearly you are not interested in enlightening an ingnoramus like myself.
I do believe in a higher being, and will entertain the possibility that said higher being has some responsibility for the natural disasters recently, so I had some sympathy for your points at first. But your refusal to have a rational discussion does your position no good at all.
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chipchap42
3/18/2011 4:57 PM EDT
I agree with paboyle and I am appalled to see EETimes apparently helping the scaremongering that the less rational media has been flinging around this week. It appears that there is no basis whatsoever to the idea that a criticality has occurred. But ask ordinary people a week from now whether there was a nuclear "disaster" and I would put money on them saying yes. In fact it's nothing of the kind and if this is the worst it gets, it's a testament to the engineers that designed and built the place, as well as those who have worked to contain the issue that nothing has really happened. The US government and others have not helped by suggesting people leave.
Personally I think this whole episode is a ringing endoresement of nuclear power rather than an indictment of it.
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piratebill
3/18/2011 11:14 PM EDT
OK Chipchap
ok so there where explosions (oxidation events) in at least 2 of the reactors. the compromised reactors are venting to the sky a mixture of what must be the top 10 nastiest elements ever known to man. there is no known way to stop the reaction as of 3/19/2011. and lastly its getting worse by the day. did i forget to mention the reactor core is lined with zirconium? some one please help me confirm this, i have only one source and am not a physicist. i read (not positive) that the zirconium lining is somewhere around 10-20 tons and will combust at 2000 degrees F. further, the fuel storage tanks are also lined with zirconium and are weighting in at 100+ tons and are also avalanching. i think only of cheap fake diamonds when i think of zircons, and the press is lies on top of stupidity so i dont know what to believe anymore.
So Chipchap,... what exactly constitutes a "disaster" in your mind?
What part of 10,000 year half life makes this a "testament to the engineers"?
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FBMcGalliard
3/21/2011 2:43 PM EDT
Why are you all wasting your time with theoretical religion? Isn't physics hard enough?
" a nuclear reaction has begun in a spent fuel rod pond"
This is clearly not true. The nuclear reactions that have been decaying all along are not being cooled sufficiently now.
And no - radioactive iodine is not the nastiest substance known. Used in liew of surgery for removal of a hyperactive thyroid.
Plutonium, the longest lived of these, is an alpha emitter. Very very short range. Just don't inhale the dust.
Radioactive cesium, soluble in water as I recall. Rain? Also a short half life, couple months isn't it?
Sr 90. Very nasty. Also not likely to go far from the site unless the smoke plume gets really high. Worry about what is, not what can be wildly imagined.
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David Ashton
3/21/2011 3:02 PM EDT
Thanks for the info. As you may have gathered, some of the comments were directed at a poster UBM-something, whose religious comments (mostly quoting a few verses of Revelation) seem to have been removed...
As I write Japan seems finally to be bringing the reactors under control, so lets hope futher disaster has been averted.
If reactor design and safety procedures improve as a result of this, some good will have come out of it.
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pixies
3/21/2011 4:58 PM EDT
Thanks for the useful info. One question I have what is the benefit of MOX vs pure Uranium fuel? And why the power company insisted to have them loaded amongst local protest?
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GPBobby
3/22/2011 7:50 AM EDT
We must put into perspective the most likely facts surrounding this nuclear power incident:
1. The plant was probably built and maintained to the highest possible and REASONABLE standards. (I don't have to mention on an engineering forum the concepts of trade-offs even when one parameter is cost.)
2. Without continuing to introduce vast amounts of CO2 into the atmosphere (and its attendant problems, whatever you perceive them to be) the ONLY timely and cost efficient source of the quantities of electricity needed in the world is nuclear energy.
3. Accidents (many fatal) are associated with any human activity in which uncontrollable variables are involved. EVERY year in the US some 20 to 60 coal miners die and in China that number rises to over 2k. Yet, we have no outrage over coal fired power plants as we might nuclear even if one soul perished. We must begin building nuclear plants as safely as possible, inland (with unsightly cooling towers) if necessary, in order to avoid a serious economic crisis.
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rpell2
3/25/2011 11:34 AM EDT
Just adding to your last point about coal fired power plants:
A recent study estimated that "...fine particle pollution from existing coal plants is expected to cause nearly 13,200 deaths [in the U.S. alone] in 2010. Additional impacts include an estimated 9,700 hospitalizations and more than 20,000 heart attacks per year."
Link: http://www.catf.us/resources/publications/files/The_Toll_from_Coal.pdf
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Salio
3/27/2011 10:21 PM EDT
I am not sure what to say about the emotions displayed in this thread. I understand that the inciddent is such that it incites emotions but at the same time we should all look at the facts and facts provoking questions. What caused the Diesels to not operate when they were suppose to? Were the DC batteries sized adequately to cope with such events? What lessons can be taken from these events to prevent such a catastrophe from happenning again? Nonetheless the above questions do not undermine the events that have ensued. In no way in my opinion should the release of any radioactive particles/gases should be taken lightly. The appropriate actions shall be taken to ensure the safety of the people in the vicinity of th reactors and elsewhere. Unfortunately now a days journalists have become Nuclear experts, which is a dangerous prospect. Journalists are reacting to this incident as they were when the health care bill was being drafted. A highly reliable source for up to date facts/information on the Japan's incident, please visit http://www.nei.org/.
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Robotics Developer
3/30/2011 6:44 PM EDT
It was my understanding (read about - not seen with my own eyes) that the generators were in the basement and got overwhelmed by the Tsunami. I also read that there were many (read here years worth) of spent fuel rods stored "on-site". I can appreciate the issues of disposal, transportation, and costs associated with spent rods as very significant, clearly we should develop safe and effective methods of recycling, disposing of the spent rods in order to avoid further safety/radiation issues in future events.
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Frank Eory
3/30/2011 8:37 PM EDT
The U.S. media has recently discovered and reported that we have over 65,000 tons of spent fuel rods here in the U.S., and the vast majority of it is stored in on-site pools -- exactly as in Fukushima.
Even if the Yucca Mountain Nevada storage facility idea had not been abandoned, we already have more nuclear waste than that facility was intended to store, and we generate another 2,200 tons every year.
Unlike some countries, we don't reprocess our spent fuel, which could dramatically reduce the quantity -- from what I have read, by as much as 75%.
So why don't we reprocess it? Because reprocessing costs money, electricity rates are regulated, and electric utilities aren't in business to lose money.
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Sheetal.Pandey
3/31/2011 7:04 AM EDT
Oh if the tragedy extends to nuclear reactors, it would be beyond controllable. Why all this happened in Japan? I really feel sad for people of Japan. hope the world bank and united nations are supporting with open arms.
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