Sciencemadness Discussion Board - Japanese nuclear reactor problems

Japanese nuclear reactor problems

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Magpie - 12-3-2011 at 19:24

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.

Sedit - 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

Magpie - 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.

Sedit - 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.

anotheronebitesthedust - 12-3-2011 at 20:51

http://www.youtube.com/watch?v=af-41E5mndk

leu - 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:

Rosco Bodine - 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.

unionised - 14-3-2011 at 12:56

Do you have any evidence for that?

Lambda-Eyde - 14-3-2011 at 13:11

Recommended read: http://theenergycollective.com/barrybrook/53461/fukushima-nu...

Twospoons - 14-3-2011 at 13:51

Thanks for that - a very interesting read.

madscientist - 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.

ScienceHideout - 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.

Rosco Bodine - 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.

Sedit - 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.

hkparker - 14-3-2011 at 20:57

Periodicvideos did a video on this recently, good explanation:

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

Twospoons - 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.

Magpie - 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."

watson.fawkes - 15-3-2011 at 04:24

Quote: Originally posted by Lambda-Eyde

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.

Rosco Bodine - 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.

Regolith - 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.

entropy51 - 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]

bquirky - 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) ?

Saerynide - 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)

Keeping up with a flow rate of 500 L/min is impressive.

[Edited on 3/15/2011 by Saerynide]

madscientist - 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.

entropy51 - 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.

Regolith - 15-3-2011 at 12:00

Saerynide is correct your talking more than 200 megawatts of residual core heating from decay of fusion products. Thats a huge pile of water, further the failed cooling systems prevent cooling the core at the speed required.

Entropy, I know amazing isn't it? It's not certain but one of the running theories behind what threw the immensely heavy, 2000 ton, reactor cover off the damaged reactor as it spiked to nearly 30GW. It's what happens when you build reactor cores so massive that a supercritical mass can be achieved in the core. Chernobyl was 3200MWT it was just far too much fuel in one core. Fukushima is a mere 784MWE by comparison. Fukushimas number 1 reactor is even smaller than 2 and 3 .

For those so interested there is an excellent documentary that can be had right online. There are more opinions found than just this about chernobyl and this one doesn't go into the reasons behind why technicians who weren't correctly trained were operating the reactor at all. However it's a great starting point.
http://topdocumentaryfilms.com/the-battle-of-chernobyl/

edit, dang spellcheck didn't have supercritical

[Edited on 15-3-2011 by Regolith]

arsphenamine - 15-3-2011 at 13:33

MIT handed the "What? Me, worry?" document over to its Nuclear Science and Engineering department for emendation.

It is much improved and worth the read.

http://mitnse.com/2011/03/13/why-i-am-not-worried-about-japa...

Sedit - 15-3-2011 at 13:35

Curious, is there no material they could fill the reactor with which the Uranium would melt and disperse in? Since its in the oxide form Im possitive it would mix with glass and seriously lower the radioactive release. Materials like Borosilicate should not only mix in the molten state with the oxide but also aid in neutron absorbing. In theory it could make handling the reactor and cooling it simpler. One of the ways they dispose of depleted fuel is by mixing it into a glass anyway but I would be concerned if they would be able to mix the compound before the temperature went to high.

madscientist - 15-3-2011 at 14:12

I think they're more concerned about a decrease in surface area at this point. Anything that joins the rods together into a single mass will do this and make it massively more difficult to cool.

gregxy - 15-3-2011 at 14:42

Its interesting to do some math:

The power for the 3 reactors was 1800Mw before the quake.

The residual power should now be <5% of that or about 100Mw
(I saw a nice graph on one website showing how the power
declines over time but I lost the link)

The heat capacity of water is ~4 kJ/kg/K if the water goes in
at 30C and comes out at 80C then each kg can carry 200kJ

So the flow rate is 500kg/sec or about 125 gallons/sec

A typical fire hydrant can put out 25 gal/sec so you will need
5 of them. Not a huge amount of water for a few big
diesel pumps.

The water mains were probably damaged and there is
no way to truck in this much water, which is why they
are using sea water. If the core is damaged radioactive
material will disolve into the water. The claim to filter the
water but how? The water probably goes out
the cooling outlet for the plant, probably far out to sea.

Magpie - 15-3-2011 at 14:50

Interesting calculation gregxy. Your calculation assumes that the water is in the vessel long enough to get heated a delta of 50C. This is where the available surface area for cooling becomes very important.

[Edited on 15-3-2011 by Magpie]

[Edited on 15-3-2011 by Magpie]

ScienceHideout - 15-3-2011 at 14:51

Telling the truth, I watched a TV show explaining everything. Doesn't sound too bad.

You may have heard, "The rods are exposed!" That simply means that the uranium supply is no longer underwater. No big deal.

The phrase Meltdown refers to when the uranium rods melt the outer shell.

And the explosions- just the engineers releasing pressure.

gregxy - 15-3-2011 at 15:17

How hot the water gets depends on the flow rate. Reduce
the flow rate and the delta T becomes larger resulting
in more removed heat per kg of water. Of course the flow
rate must be high enough to ensure even cooling.
And if the water becomes hot enough to boil the back
pressure could prevent pumping water in. I'm sure they
planned for all this using the regular back-up.

If the core goes dry it is a big problem. I suspect it only takes
minutes to reach the melting point for the zicronium tubes.
(If you know the mass of the core you can figure it all out).

And if the core becomes hot enough to deform water flow
will become non-uniform resulting in hot spots and more
heating etc.

But the "worst should be past" since the heat output
declines with each day.

madscientist - 15-3-2011 at 15:34

ScienceHideout: when fuel rods are exposed, they begin to melt. When they are completely molten, it's a meltdown.

Does <a href="http://www.youtube.com/watch?v=T_N-wNFSGyQ">this</a> seriously look like deliberate venting of steam? If that's what it is, I won't be buying any pressure cookers from Japan!

entropy51 - 15-3-2011 at 15:58

Quote: Originally posted by ScienceHideout

Telling the truth, I watched a TV show explaining everything. Doesn't sound too bad.

You may have heard, "The rods are exposed!" That simply means that the uranium supply is no longer underwater. No big deal.

The phrase Meltdown refers to when the uranium rods melt the outer shell.

And the explosions- just the engineers releasing pressure.

As madscientist said, fuel rods not cooled by water are heating up. The rods continue to generate energy due to decay of radioactive fission products. If it is not removed by flowing water, where does it go? Nowhere. It heats the rods up until the zirconium cladding begins to react exothermically with the steam and generate hydrogen and more energy, which further raises the temperature. You need to watch better television, or God forbid, read a science book.

gregxy, your 1800 MW figure is the electrical output of the plant. The thermal power is about three times as much.

I love this thread. It is a classic example of how intellectual arrogance finds itself in company with ignorance.

gregxy - 15-3-2011 at 16:04

I made a mistake in my earlier post, The decay heat at
this point should be < 0.5% of the original reactor power
so only 10Mw of power needs to be removed (for all 3 reactors)

Or about 12 gallons/sec of water, which can be supplied by
one 3" fire hose.

http://en.wikipedia.org/wiki/Decay_heat

Sedit - 15-3-2011 at 16:29

Just to play devils advocate here for a second I want to remind everyone that all our assumptions are based on the fact that they are telling the truth about the control rods being in place. Mind you nothing they have said so far has been true and its all be a PR campain, that I don't disagree with really, to keep the general public from going into all out crisis mode. They got enough on there plate to be worried about sudden death.

I would think logic would dictate that the secondary chain reactions would be weaker then the primary one. However even with the control rods in place everyones saying the heat is comming from the secondary reactions. I doubt this as it sounds unreasonable. If the control rods can stop primary fission why can't they control the neutrons from a weaker secondary reaction? With the control rods in place the neutrons causing the heat should be absorbed into the control rod and primary and secondary should cease and prevent the chain reaction from taking place all together.

entropy51 - 15-3-2011 at 16:35

Quote: Originally posted by Sedit

With the control rods in place the neutrons causing the heat should be absorbed into the control rod and primary and secondary should cease and prevent the chain reaction from taking place all together.

What is this "secondary chain reaction"? If you mean the decay heat, that is due to the radioactive decay of the fission products that were formed while the reactor was in operation. There are no neutron reactions involved at this point. Once the fission products were formed (before the shutdown on Friday), they will decay according to their half-lives and nothing can slow that down, speed that up, or stop it. The energy of the decay just has to be removed or it will heat up the fuel.

entropy51 - 15-3-2011 at 17:13

Quote: Originally posted by gregxy

I made a mistake in my earlier post, The decay heat at
this point should be < 0.5% of the original reactor power
so only 10Mw of power needs to be removed (for all 3 reactors)

Or about 12 gallons/sec of water, which can be supplied by
one 3" fire hose.

http://en.wikipedia.org/wiki/Decay_heat

So greg, do you think those poor guys who are down there at Fukushima Daiichi tonight, getting their innards cooked, trying to save that plant and a lot of lives, didn't think of your simple solution?

I guess those nuclear engineers aren't smart enough to just stick a fire hose in it, call it a day, and go home.

Or. according to your calculation, why don't they all piss on it at the same time? That would provide the flow rate you calculated, wouldn't it?

Oh wait! You don't suppose you could be missing some subtle nuance of heat transfer or thermodynamics or hydraulics?

Sedit - 15-3-2011 at 18:16

Quote: Originally posted by entropy51

Quote: Originally posted by Sedit

No not the latent heat, the supposed breakdown of the formed radioactive compounds. Everyone has been focused on the heat produced not from the primary fission of the Uranium but the fission of the biproducts. I don't feel they would be sufficient to heat the reactor to over 3000 degrees C in 45 minutes with the control rods in place as everyone is suggesting.

[edit]

Ehchem.... 3" firehose.... pissing, your sure are an optimist aint ya Entropy

[Edited on 16-3-2011 by Sedit]

edit2

Once again im on point, don't hate me for it I just can't help myself.
http://www.aolnews.com/2011/03/15/japan-nuclear-reactor-stor...

Basicly,,, there fucked to put it bluntly. They have 4 reactors in the same complex all over heating. They are left with nothing but firehoses at this point to put out a fire... partial meltdowns have happened in them and its a waiting game now.

Its over! Whatever can happen will happen, They are wasting there time fighting it and should evacuate everyone and watch from a safe distance as there poor planning comes to light.

At what point do you toss in the white flag and run for your mother fucking lifes?

[Edited on 16-3-2011 by Sedit]

Elawr - 15-3-2011 at 20:27

I agree... the garbling of technical details by the press media reflects the appalling loss of general scientific knowledge suffered by our society...So, this is the reason I can watch TV news no longer than 5 or 10 minutes before my eyes began to fog over and I start drooling! To me, it's as scary as the idea of nuke meltdown fallout raining down on my head.

I turn to Sciencemadness.org for the salient facts.

So, I am I correct in understanding that , although at least 4 separate nuclear power facilities have been compromised by Japan earthquake, only one of these is actually impending meltdown albeit in 3 of 4 of its reactors?

Some older reactor designs depend upon the neutron-slowing effect of cooling water to help control fission reaction, thereby inherently unstable in event of coolant loss. Surely this is not the case here... are not modern reactors safer in this regard? (or is it other way around...)

I see your point Sedit, if the radioactive decay products (embers, as it were of the fuel consumed) release such tremendous energy,....then.. uh

Truth is, I think, no one quite knows for sure. Quite a complex mix of unstable nuclides of all different half-lives making up that unimaginable hell cauldron bubbling at the bottom of those reactors. I sure as hell would not want to study it!

Think I'll just go watch a favorite "Outer Limits" episode I once taped: "The Production and Decay of Strange Particles".

Now might be a good time to put your surplus KI up for sale on eBay...:-)

[Edited on 16-3-2011 by Elawr]

Regolith - 16-3-2011 at 00:03

Elawr, your mostly correct. There are several nuclear sites in japan (they get more than 30% of their energy from nuclear), most of them achieved cold shutdowns following the quake, albeit several are scrambling to make sure they have diesel fuel for cooling. In many cases there pumping out water from access points (flooded from the tsunami) they need to get into to attach power lines from generators.

At the Fukushima plant they have 6 reactors, at this point reactors 1, 2 and 3 are in meltdown. Meaning that even a small part of the core (70 percent of one core apparently

) has been exposed and has melted. This is the end of a reactor, even before they sprayed in seawater to cool the reactors (seawater contamination requires decommissioning this type of reactors on its own). Reactor 4 seems to be stable but the cooling pond that houses the fuel used in the last loading has boiled dry and has broken out in flames. It doesn't mean the end of the world however. These units were built with this (failsafe) in mind and every day that passes means another day of shutdown and the latent fission products are decaying more and more and cooling down.

The type of reactor where the water leaving the core causing a power rise is what happened in chernobyl. Modern designs try to have the opposite or have a core that is designed to run at maximum temperature without a human intervening. Pebble bed reactors are one such reactor. As mentioned above with a PBR you really can just run for your life and ignore it until you have the systems ready to bring it back under human control. On the other side of the scale is what you mention, which is basically a raw nuclear pile, chernobyl, in its primitive design, it lacked only the people standing above it with buckets of water reminiscent of the chicago pile.

All this said, they have detected a crack in one of the calandria(reactor vessels) at fukushima I and that IS very bad if the crack extends all the way inside. Scientists here will be well aware of low viscosity molten products that can flow just like water and need only the tiniest space to get out. Provided they can prevent the core melting completely this can still be dealt with.

I read the article sedit posted above and this sticks out to me as shoddy journalism.

"A U.S. nuclear expert said he feared the worst. "It's more of a surrender," said David Lochbaum, a nuclear engineer who now heads the nuclear safety program for the Union of Concerned Scientists, an activist group. "It's not like you wait 10 days and the radiation goes away. In that 10 days things are going to get worse."

Yes it is like you wait 10 days. (further he's an activist group, HELLO ? AOLnews you guys ask questions? or just nod and smile ?) The longer you get from the time the core was online the cooler it's going to become. The isotopes created in the reactor often have short half lives a month is often required to get to a full shutdown. At a certain point it wont boil water anymore. This isn't the world ending disaster people are blowing it into its being driven by a hatred for nuclear power at many news organizations. If they can keep containment on the reactor in any form, it will be removable by barge to a proper disposal site which is what was slated anyway in a few years.

I'm an advocate FOR nuclear power. Even after this, with the building collapsing and the workers now abandoning the site due to radiation, fyi, it's likely the crack in the reactor DOES go all the way through. Japan is a tiny island what other way do they have for power generation? Personally I think we should be using discreet nuclear reactors like those of the toshiba lithium moderated or the smaller designs from adams atomics, which has designs small enough to replace diesel sets in large watercraft and buildings.

A chernobyl this will not become a month from now this won't be in the news anymore as obama pushes for his next election or the next major disaster comes up. Everyone on earth during chernobyl was able to step outside and detect the increase in background radiation from that accident. The difference in scale of this disaster is enormous.

bfesser - 16-3-2011 at 07:41

Has anyone else noticed the sudden increase of listings for potassium iodide on eBay since these events? Some of it's listed for absolutely <a href="http://cgi.ebay.com/Potassium-Iodide-/260753097989">ludicrous prices</a>!

Chordate - 16-3-2011 at 07:51

Even scarier are the people bidding 50 dollars on a bottle of iodine/potassium iodide solutions.

hissingnoise - 16-3-2011 at 08:12

The serious problems Japan now faces are the result of human error!
The worst-case-scenario just wasn't planned for . . .
The generators should have been built to be impervious to all tsunami!
Lessons will, we hope, be learned from this catastrophe but it's coming at enormous cost to a people already pretty devastated.
The entire thing is beyond words, essentially . . .

Magpie - 16-3-2011 at 08:27

Many years ago when I worked in nuclear waste management we somehow ran across a flyer for KI pills. It had a picture of the grim reaper and something about "this is not the government's 'get-out-of-town pill.'"

What I can't understand is why they were not successful at flying in diesel generators. With sufficient pumping capacity it seems that they could have had safe and normal shutdowns, and kept their spent fuel pools cool. I wonder if we are not being told the whole story here.

-----------------------------------

Use of normal cooling water (deionized, I would think) would also depend on the piping and heat exchangers that exchange heat with seawater retaining integrity. After an 8.9 earthquake this may well not be the case. These are just my speculations, I've heard no such reports from the Japanese.

[Edited on 16-3-2011 by Magpie]

[Edited on 16-3-2011 by Magpie]

Saerynide - 16-3-2011 at 08:48

I think they need to extend the evac radius because when things get bad, there won't be time to get everyone out, and everyone trying to run will make it even harder for them to get out. Hell I wouldn't want to be 12 miles away when a reactor (or all 4) goes critical - you'd be able to see it out your window!

I really hope they are collecting the concrete necessary and keeping it close on standby, along with remote control dump trucks to pour it so that when it comes time to abandon ship and run for their lives, the remote control equipment can get started right away pouring cement.

Lava shouldn't be coming out the bottom before they decide they need it...

gregxy - 16-3-2011 at 10:17

Quote: Originally posted by entropy51

Quote: Originally posted by gregxy

Of course it is harder than connecting a fire hose to the reactor. And the people that designed the thing know all this to 5 decimil places. I'm just trying to get some understanding
of the magnitude of the problem since you cannot tell anything from the media reports. Even if I'm off by 10X it
is still managable situation. If you don't agree with it
fine. Present a better calculation, anyone can throw stones.

They have made it through the most critical phase which
was the first 24 hours after shut down. In about 5 days
the media and everyone else will tire of the whole thing.
It will be a huge mess to clean up but its unlikely there will
be a single death due to radiation.

Sedit - 16-3-2011 at 11:57

Quote: Originally posted by gregxy

It will be a huge mess to clean up but its unlikely there will
be a single death due to radiation.

I want to agree but given the fact that the news crews covering the story from some distance away have just tested positive for radiation even after a scrub down means there may be more then they are letting on to. They didn't say what strength the reading they got on him just that it was showing up.

I guess all there is to do is wait a couple weeks and see. If its still a big problem then, then they are lying about the control rods being in place which may be a real possibility since you had an extremely powerful earthquake followed with a huge wave. Its obvious they are patting there people on the head and telling them its alright but there is a huge question as to how bad the situation really is. There word is worth nothing and honestly little of there facts are.

ScienceHideout - 16-3-2011 at 12:17

Quote: Originally posted by madscientist

ScienceHideout: when fuel rods are exposed, they begin to melt. When they are completely molten, it's a meltdown.

Does <a href="http://www.youtube.com/watch?v=T_N-wNFSGyQ">this</a> seriously look like deliberate venting of steam? If that's what it is, I won't be buying any pressure cookers from Japan!

Notice the "explosion" came from here. To me, those look like functional cooling towers.

Magpie - 16-3-2011 at 13:50

Quote: Originally posted by ScienceHideout

To me, those look like functional cooling towers. snip

Actually I haven't seen any structure that looks like a cooling tower. Are you sure that the final cooling loop is not just using seawater cooled heat exchangers?

------------------------

FYI, here's an NRC document on BWR design showing the Mark I, II, and III:

http://www.nrc.gov/reading-rm/basic-ref/teachers/03.pdf

[Edited on 16-3-2011 by Magpie]

entropy51 - 16-3-2011 at 16:48

Quote: Originally posted by gregxy

Apparently you think that one can calculate the thermal-hydraulics of a nuclear reactor under going a severe accident using back of the envelope calculations. As I pointed out, your heat source is a factor of 3 too low because you don't know the difference between the electrical and thermal ratings of a reactor. Your heat source is also low by orders of magnitude because you don't realize that the zirconium cladding is reacting with superheated steam to produce much more energy than the decay heat. You also assume that all the energy enters the coolant with perfect heat transer, ignoring the Leidenfrost temperature limits on heat transfer from superheated metal. You don't understand boiling heat transfer and departure from nucleate boiling. I will let my stone throwing stop with that.

Twospoons - 16-3-2011 at 16:56

Its also not simple as they will be pumping against an awful lot of steam pressure. IIRC the normal operating temp for the reactor is around 250C - which puts the steam pressure at ~39 atmospheres

.

Personally, I think they've done bloody well so far, when you consider what they've been hit by : 9.0 quake and a monster tsunami - far outside what had been considered. Its easy to look back and say "oh, they did *this* wrong, they should have been better prepared etc". But, as with any engineering project, you have to draw a line somewhere otherwise nothing would ever get built. There's no crystal ball handed out with the engineering degree.

[Edited on 17-3-2011 by Twospoons]

madscientist - 16-3-2011 at 17:23

Quote:

But, as with any engineering project, you have to draw a line somewhere otherwise nothing would ever get built.

With regards to Fukushima, that clearly would've been a good thing. The line wouldn't have needed to be drawn too far away either, seeing as the problems with the reactor design, and the obscenely dangerous location, were very well known.

Also, I don't consider losing control over the situation, leaving others to speculate whether it'll dump lethal doses of radiation all over Japan, to be "doing well." A number of people have died, more may die yet from injuries, and there will surely be more cancer deaths due to the fallout already released. There's been four huge explosions, two of the containment vessels are cracked, multiple fires have broken out near massive quantities of nuclear waste, and the site is so radioactive now that approaching it may soon become a suicide mission. The waste pools are apparently dried up, and if that fuel bursts into flame in the open atmosphere, it will make Chernobyl look like a joke. Good luck throwing water on it at that point, too - counterintuitively, it could result in an inadvertent criticality.

DDTea - 16-3-2011 at 18:40

Someone pointed out the Fukushima One station's "dangerous location." From what I can tell, it is a practical reality and maybe we're fortunate that it is located where it is: next to the sea. At least they can pump in sea water in the event of this kind of emergency and so far, much of the radioactive vapors have been carried out to sea instead of solely traveling over land and population centers.

That said, the operating conditions are exceedingly dangerous. The logistics are a nightmare that you or I simply cannot imagine. Suppose they do order an immediate, total evacuation of an area of 30km or so in a country with a population density as high as Japan. Short of teleportation, they'd have to open up both directions of their highways. The situation is further complicated by massive debris fields and blocked roads. The road traffic would make it a lot more difficult for emergency vehicles to get into the area. They would need to setup emergency shelters, they would need to ration food, there may be issues of law and order.

I can't imagine there being a point where everyone says, "Run for your lives!" and abandons ship. That would create a situation in which it is probably better to die than to survive. With that in mind, the Japanese authorities are probably sparing no efforts in containing the situation as much as possible. Any public panic would complicate that and may very well be the straw that breaks the camel's back. Should the situation suddenly go downhill quickly anyway, it may be that those who remain in the evacuation zone are going to die anyway. In their near-term future, it may be easier to simply let them die as soon as possible than to burden the already exhausted resources of the post-disaster country.

I hate to sound so cold, but these are the facts facing decision-makers in the event of these catastrophes. It's easy to say, "They could be handling this better." By what standard? When's the last time there was a 9.0 earthquake, tsunami, AND nuclear disaster in a country with such a high population density and such a huge role in the global economy? They are currently setting the standard. Think about that.

What I'm saying is it's easy to say what the Japanese government or TEPCo "should" be doing, but let's all agree: talk is cheap.

Twospoons - 16-3-2011 at 18:54

Did you read the whole sentence? Its been hit by forces so far outside the design parameters its amazing its all still standing. They've lost power, back-up power, back-up back-up power, had several explosions - and still haven't had a major leak. I call that heroic! Would you want to be on that site, desperately trying to cool 3 reactors and a spent fuel pool in the aftermath of a nationwide disaster? Things may still end really badly, but give them credit for trying.
I wish them the best of luck.

madscientist - 16-3-2011 at 19:12

Quote:

Someone pointed out the Fukushima One station's "dangerous location." From what I can tell, it is a practical reality and maybe we're fortunate that it is located where it is: next to the sea.

The location is why the disaster happened - the tsunami flooded the diesel backup generators, disabling them.

Quote:

What I'm saying is it's easy to say what the Japanese government or TEPCo "should" be doing, but let's all agree: talk is cheap.

My complaints don't pertain to what they're doing now, but what they should have done before - namely, not build a nuclear power plant right next to the ocean in a region prone to earthquakes and tsunamis. They didn't even bother to build it to survive the strongest expected earthquake (or tsunamis in any way whatsoever). Additionally, they ignored warnings from GE engineers that the containment vessel was basically garbage.

Twospoons, I do not mean to criticize the operators of the plant. Any attempt to do so would, in my eyes, amount to cruel slander. The accident is not their fault, and their efforts to mitigate its consequences have been nothing less than selfless and heroic. They did not make the decision to build the plant in such a poor location, to cut corners on costs for safety mechanisms, to implement a poor design to save money, or to build a nuclear power plant at all.

Quote:

and still haven't had a major leak.

They've had to evacuate the plant due to very dangerous radiation levels, and several workers have been hospitalized for acute radiation sickness. It doesn't have to be as significant as Chernobyl to be considered "major," or to have wide reaching implications for the health of staff and people in surrounding areas.

DDTea - 16-3-2011 at 19:17

Earthquakes are almost a daily occurrence in Japan. The Fukushima power stations (and all power stations in Japan) have survived hundreds of earthquakes, including many strong ones. That's a good track record. As far as where they should have been located, though, again: I think placing it by the sea showed a lot of foresight (although the issue of the backup generators is going to warrant a serious investigation).

Imagine if they'd placed the power stations inland, suppose on higher terrain to safe-guard it from tsunamis. What if the reactor cooling failed for a different reason? There would be no feasible way to cool them down. More than that, radioactive clouds would drift overland and possibly over cities. Dangerous isotopes could fall out in the rain, contaminating groundwater, livestock, and plants. Again, it's good that Fukushima One is surrounded 180 degrees by water.

Quote:

Did you read the whole sentence? Its been hit by forces so far outside the design parameters its amazing its all still standing. They've lost power, back-up power, back-up back-up power, had several explosions - and still haven't had a major leak. I call that heroic! Would you want to be on that site, desperately trying to cool 3 reactors and a spent fuel pool in the aftermath of a nationwide disaster? Things may still end really badly, but give them credit for trying.
I wish them the best of luck.

I read the sentence, but I was pointing out that a lot of the analyses I've seen are very simplistic--not that yours was, you hit the nail on the head. Expanding on what you said, all four reactors at Fukushima Number Two (Dai-Ni) successfully SCRAM'd and although there was a hiccup with the coolant systems in reactors 1, 2, and 4, all were brought online and all reactors are below 100 C right now--after the same set of circumstances that hit Fukushima Number One.

Nuclear power accidents are horrible and really, we won't even begin to understand the effects for at least a decade. The radiation effects will make themselves known in stillbirths, blood cancers, development disabilities (physical and mental), etc. That said, hydroelectric power still has caused the most severe accidents in terms of loss of life and destruction of property.

Twospoons - 16-3-2011 at 19:22

Quote: Originally posted by madscientist

They didn't even bother to build it to survive the strongest expected earthquake (or tsunamis in any way whatsoever).

As it happened the reactors survived a quake much bigger than planned for. If not for the tsunami, all would be well.
I believe they did have a sea-wall to stop tsunami - it was simply overcome by the exceptionally huge wave generated by this event. You can say it should have been bigger - but how much bigger? 10m? 20m? 100m?

If there is a silver lining to all this misery, it will be a global review of reactor safety, and contingencies for multiple failures. Lets hope the accountants don't get in the way.

Until nature throws us another curve ball ...

@DDtea : my comment was not directed at you - your post went up while I was typing

[Edited on 17-3-2011 by Twospoons]

DDTea - 16-3-2011 at 19:28

Quote: Originally posted by Twospoons

If there is a silver lining to all this misery, it will be a global review of reactor safety, and contingencies for multiple failures. Lets hope the accountants don't get in the way.

Until nature throws us another curve ball ...

Also a good point. I don't mean to change the topic, but this raises serious questions about Iran's desire to adopt nuclear power. That is also an extremely seismically active region of the world and many powerful earthquakes have hit the country (e.g. 2003 Earthquake in Bam).

It's also good to see questions being raised about reactors along the West coast of the United States. Some of the debate may be from hysteria, but in any case it's better to allay fears with honest facts and debate than to simply disregard them.

Sedit - 16-3-2011 at 19:50

Sorry to stray a little bit here but being as active as this story is I have no doubt it will get right back on topic in no time,

Does anyone know why they even build these things above ground? Why not bury them as deep as possible so that in case of an accident its nothing major at all. Underground bomb testings happened on a major scale as evident by the google earth pictures of Area 51, It looks like the surface of the moon its so cratered. However they still managed to plant the next device shortly after the last went off meaning radiation underground is of little concern.

What use comes from placing these things to the elements where they could go off and do a great amount of harm?

Twospoons - 16-3-2011 at 19:54

I was wondering the same thing. $ probably. $ always get in the way of truly great engineering.

Magpie - 16-3-2011 at 19:59

Quote: Originally posted by DDTea

It's also good to see questions being raised about reactors along the West coast of the United States. snip

Are you talking about future possible constructions here? There's currently only two operating nuclear stations on the US West coast, ie, San Onofre and Diablo Canyon.

NRC Region Four (West)

* Arkansas Nuclear One, Arkansas
* Callaway, Missouri
* Columbia, Washington - formerly WNP-2
* Comanche Peak, Texas
* Cooper, Nebraska
* Diablo Canyon, California
* Fort Calhoun, Nebraska
* Fort Saint Vrain, Colorado (Decommissioned)
* Grand Gulf, Mississippi
* Hallam, Nebraska (Decommissioned)
* Hanford N Reactor, Washington (Retired - see Plutonium Production Reactors below)
* Humboldt Bay, California (Decommissioned)
* Palo Verde, Arizona
* Pathfinder, South Dakota (Decommissioned)
* Rancho Seco, California (Decommissioned)
* River Bend, Louisiana
* San Onofre, California
* Sodium Reactor Experiment, Santa Susana Field Laboratory, California (Accident 1959, Closed 1964)
* South Texas Project Electric Generating Station, Texas
* Trojan, Rainier, Oregon (Decommissioned)
* MSTR, Missouri
* Vallecitos, California (idle research center)
* Waterford, Louisiana
* Wolf Creek, Kansas

[Edited on 17-3-2011 by Magpie]

Regolith - 16-3-2011 at 22:41

This is likely about to get better. They have almost finished the repairs to the power lines that activate the pumps to bring the cooling systems back online. The 50 workers who are risking their lives to keep the stricken plant running and are leaving the site and returning in teams to avoid the bulk of radiation are all heros.

Re. underground reactors. Think for a moment about that... Ground shakes and the say 40,000 tons of material above the reactor underground breaks free from the sides of the earth and is supported by nothing but the roof of the reactor, crunch. Further underground it's going to be already right beside the water table... Really bad idea. Watch the video link I posted above it talks about chernobyl and the water table. Running reactor with neutron output plus groundwater equals radioactive groundwater. Hence why they aren't underground.

watson.fawkes - 17-3-2011 at 05:14

Quote: Originally posted by madscientist

The location is why the disaster happened - the tsunami flooded the diesel backup generators, disabling them.

I want to underline this point. The standard practice for life safety in tsunami zones is "vertical evacuation": get the people into a tall building above the surge level. I can't figure out why the design engineers didn't take the same approach, in advance, for the backup generators. Just build a four-story building near to the reactor (but not too near) and put the generators on the top floor. Such a building can be built to withstand even a 9.0 earthquake with adequate amounts of structural steel. Better steel geometry would help, too. Steel in most buildings is on a cubical grid of some form, usually with diagonal reinforcement in one of the major planes. Building the frame on the crystal space-filling plan of the octet truss would give such a building a quite high strength-to-mass ratio.

If you don't believe in getting backup power higher than the surge level with a building, just pick another site for the reactor that's high enough above sea level.

MrHomeScientist - 17-3-2011 at 06:19

Slightly off topic, I've gotten a huge surge of interest in my YouTube video on making potassium iodide since the disaster. Many people are saying most places are sold out of KI tablets, and asking where to get the I2 and KOH for the reaction so they can make it themselves. The reaction, FYI, is 3I2 + 6KOH --> KIO3 + 3H2O + 5KI

I've been cautioning people to not try eating anything made in the lab, because I would never consider it. I just can't be sure of the purity of my reagents, and the product is almost certainly contaminated with excess I2, KOH, or KIO3.

While I'll still go on saying that, is that actually the case? I2 can be easily purified by sublimation, and the KI by multiple recrystallizations. According to KI's wiki page the dosage for adults is only 130mg/day, so even if there were impurities they would be almost at trace levels at that quantity. I'm starting to wonder myself if it's safe or not. As I've said, I'm leaning towards no.

gregxy - 17-3-2011 at 09:59

If you believe in global warming, then nuclear energy is really the only choice. To supply the energy needs for the USA requires 20,000 square miles of solar collectors. I can't
imagine building 20,000 square miles of anything. Here is
an interesting article on that topic:

http://www.scientificamerican.com/article.cfm?id=a-solar-gra...

However that approach will not work for Japan due to its
limited area and northern location. The growing energy
needs of China will present some real interesting issues.

Workers die in coal mining accidents, you just don't hear that
much about it. Workers were killed in the recent BP accident
(which did not turn out nearly as badly as everyone thought).
Wars are fought over oil.

If there were a simple solution, then this problem would have
already been solved.

madscientist - 17-3-2011 at 11:20

Quote:

I can't figure out why the design engineers didn't take the same approach, in advance, for the backup generators.

I would imagine this had been considered, but wasn't implemented due to cost cutting from above.

It was crazy to plop something sensitive to flooding adjacent to the ocean in an area prone to tsunamis and hurricanes. It's on the level of smoking cigarettes in a meth lab in a densely populated urban area - completely reckless and irresponsible.

gregxy: Solar allows the possibility of on-site power generation, which means avoidance of transmission losses. 20,000 square miles becomes a lot less intimidating when you consider the total area of all roofs in the US. The technology is also finally starting to become economical.

With nuclear power, acute radiation poisoning deaths indeed are comparable in number to coal mining. What's of concern, however, are the number of deaths, miscarriages, birth defects etc. that follow. For Chernobyl, estimates for deaths caused range from 4000 to a million. Cancer deaths have been often grossly understated by government and industry studies (both having an ulterior motive to gloss over the damages), who tend to only follow exposure victims for the first ten years - the cancers typically develop after a ten year "incubation period." Radiation means cancer and death, period.

Three major disasters in thirty years is not my idea of a good track record for the nuclear industry. And lord knows how many "minor" disasters have occurred that we don't know about. Considering that contaminated sites will remain hazardous for thousands, if not hundreds of thousands of years (in the case of the Chernobyl site), this frequency of occurrence is unacceptable. It's entirely possible, with the quantities of radioactive materials around, for us to render our planet uninhabitable. All the coal we've burned for hundreds of years has failed to do so, but the waste from half a century of nuclear energy is completely capable of it.

I see some similarity to going on a crime spree to fund a drug habit, hoping to get lucky and not get caught, instead of just cutting back on the drugs. We're gambling. We can only plan for what we foresee, and these accidents occur due to what is unforeseen, unrecognized in its significance, or greedily ignored. There will be more accidents. There always are.

Nuclear power is not even cheap or economical anyway. When you remove government subsidies, it becomes comparable to solar and wind power.

Arthur Dent - 17-3-2011 at 11:48

Aren't there graphite rods in these japanese reactors? In case of a complete catastrophe, an emergency shutdown, called SCRAM is supposed to automatically take effect, and these graphite rods are supposed to drop by the force of gravity alone into the core of a reactor, effectively separating the fuel rods from each other and neutralizing the reactor completely...

Or is this a completely different system that doesn't use that security method?

Robert

quicksilver - 17-3-2011 at 12:40

Quote: Originally posted by madscientist

The location is why the disaster happened - the tsunami flooded the diesel backup generators, disabling them.

This is such a significant point that (IMO) it should be the focus of the issue. The level of safety on many things depends on orientation and location. A motorcycle is substantially safer where there is less (or no other) traffic; just as rifle ranges have back-stops, etc. Setting up any condition that is influenced by exterior stimuli (or lack there-of) is placing an "unknown" in the equation.

hissingnoise - 17-3-2011 at 13:06

I agree qs, hindsight is a great thing but we all know that the designers of the plant had at the time believed that the chances of a 'quake occurring at the magnitude of the one that hit were so vanishingly small that safeguarding against such a scenario would have looked like expensive overkill . . .
There seems to be an element of sheer bad luck in all that's happened in Japan!
And things are unlikely to get much better any time soon.
It must be extremely frightening and depressing to have to live through a disaster of this size and complexity.
And the stoicism of those people we've seen on our screens is remarkable.
What more can one say?

gregxy - 17-3-2011 at 14:43

Quote: Originally posted by entropy51

Quote: Originally posted by gregxy

Your right I assumed the ~600MW was thermal when it is really the electrical output, so the residual power for each reactor is 3X higher or on the order of 90MW. I also
assumed that the water left the reactor as liquid at 80C, which seems about right if the backups had worked.

My calculation is based on conservation of the energy
and says nothing about the rate of transfer however,
the reactor was designed to transfer 1800MW so heat
transfer at 90 MW should not be an issue if they can keep water in it. Yes there will be complex heat transfer effects if
the rods are exposed, but if that happens you are f*cked anyway.

If you want to assume that the water leaves as steam, then
you need to include the heat of vaporization 2260kJ/kg
which is 10X more than I assumed and reduces the water
flow needed by 10X. Of course the pressure from the steam
will make it harder to pump water in.

As for energy from the Zr, my guesstimate is there are 10,000 Kg in there or ~ 1e5 moles
Zr + 2H2O -> ZrO2 + 2H2 - 430kJ/M
or 4.3e10J total energy if it all reacted.
This equals the residual power output (90MW) for about
8 minutes. This reaction can further heat the exposed
rods, but it does not seem like a large factor in the overall
energy flow.

Its also interesting to figure out how long it takes the core
to melt if there is no water. The wikipedia BWR article gives
the mass of UO2 in a BWR as 1e5kg. The average
specific heat for U2O over 300K to 3000K is ~400 J/kg/K
So the energy is 400 * 3000 * 1e5 = 1.2e11 J which
means exposed rods melt in about 20 minutes.

YMMV, Don't try this at home....

hkparker - 17-3-2011 at 16:29

Quote: Originally posted by MrHomeScientist

Slightly off topic, I've gotten a huge surge of interest in my YouTube video on making potassium iodide since the disaster. Many people are saying most places are sold out of KI tablets, and asking where to get the I2 and KOH for the reaction so they can make it themselves. The reaction, FYI, is 3I2 + 6KOH --> KIO3 + 3H2O + 5KI

I've been cautioning people to not try eating anything made in the lab, because I would never consider it. I just can't be sure of the purity of my reagents, and the product is almost certainly contaminated with excess I2, KOH, or KIO3.

While I'll still go on saying that, is that actually the case? I2 can be easily purified by sublimation, and the KI by multiple recrystallizations. According to KI's wiki page the dosage for adults is only 130mg/day, so even if there were impurities they would be almost at trace levels at that quantity. I'm starting to wonder myself if it's safe or not. As I've said, I'm leaning towards no.

I think its plenty safe, KI has a very high LD50 and KIO3 is sometimes used in anti I2131 pills. As long as your sure of no KOH or I2 contaminates to a reasonable degree. But like you said the doses are extremely small. I have a few hundred grams of reagent / A.C.S. KI that I have as a reagent, and would feel safe taking it if radiation level increased in the states, but I don't think that will be a problem this far away.

entropy51 - 17-3-2011 at 16:35

Quote: Originally posted by madscientist

It was crazy to plop something sensitive to flooding adjacent to the ocean in an area prone to tsunamis and hurricanes. It's on the level of smoking cigarettes in a meth lab in a densely populated urban area - completely reckless and irresponsible.

If you check, you will find that any power plant, nuclear or not, has to be situated near a large body of water to provide cooling. In Japan, that's the ocean. I will resist the temptation to add "Duh!" The designers perform a statistical analysis of weather patterns and geologic upsets and identify a set of conditions that is expected to occur no more than once in 100 years. Then they design against that hazard. With large numbers of reactors operating over long time periods, every now and again one will face a hazard exceeding the design conditions. Fukushima was designed to withstand a Design Basis Earthquake of 7.9, very severe. Nature threw a curveball of 8.9. It happens. You cannot afford to design every plant to withstand an infinitely strong earthquake.

Quote: Originally posted by madscientist

With nuclear power, acute radiation poisoning deaths indeed are comparable in number to coal mining. What's of concern, however, are the number of deaths, miscarriages, birth defects etc. that follow. For Chernobyl, estimates for deaths caused range from 4000 to a million.

The only fatalities due to radiation in the nuclear power industry were 28 who died after Chernobyl. It is not unusual for more than that many coal miners to die in a single accident. Your figures are wrong. Care to cite a reference for a million dying as a result of Chernobyl? That's wrong too. Please support your assertions with some data. Study after study has shown that not one single death occurred as a result of Three Mile Island, the worst nuclear power accident in the United Sates.

Quote: Originally posted by madscientist

Nuclear power is not even cheap or economical anyway. When you remove government subsidies, it becomes comparable to solar and wind power.

When you remove the subsidies and tax breaks given to the oil, gas, coal and utility industries, there is no cheap or economical way of generating electricity.

Every advanced modern technology is a deal with the devil. Nuclear power is no exception.

DDTea - 17-3-2011 at 17:23

Quote: Originally posted by Arthur Dent

Aren't there graphite rods in these japanese reactors? In case of a complete catastrophe, an emergency shutdown, called SCRAM is supposed to automatically take effect, and these graphite rods are supposed to drop by the force of gravity alone into the core of a reactor, effectively separating the fuel rods from each other and neutralizing the reactor completely...

Or is this a completely different system that doesn't use that security method?

Robert

The control rods contain Boron or some other substance with a high neutron-capture cross section ("neutron poisons"), which moderate the nuclear reaction. They're built on a fail-safe mechanism, as you described: if there is a sudden power loss, they will drop by force of gravity into the reactor. It doesn't separate the fuel rods, but simply captures the neutrons and poisons the nuclear reaction.

That said, the reactors did SCRAM. However, the core is still very "hot" (both thermally and in terms of radioactivity) and that's where the issue is coming from. I know next to nothing about nuclear chemistry, so I won't try to expand on that further!

Again, pointing out the elephant in the room: the situation is normal at Fukushima Dai-Ni power station, which experienced the same 9.0 earthquake and massive tsunami as Fukushima Dai-Ichi. Dai-Ni also lost power to its coolant pumps, but they were brought online and the reactors are now all offline.

What that tells me: the problem wasn't the earthquake or tsunami. Those were contributing factors. By analogy: lab accidents do not happen for only ONE reason. They result from a combination systematic safety failures, unforeseeable situations, bad luck, etc.

This may shed some light on the situation: http://cnic.jp/english/newsletter/nit117/nit117articles/nit1...

TEPCO has a history of data falsification.

Quote: Originally posted by hkparker

Don't do this. Any potential benefits are far outweighed by the risks. Pharmaceuticals are produced according to extremely strict specifications (look up GMP's and the Pure Food and Drug Act). You have no idea what's in your tap water, your reagents, on your equipment, etc. I'm not simply referring to chemical contamination because that's only part of the problem: I'm referring to pyrogens, bacteria, and who knows what else.

Besides, KI only protects you from Iodine-131's accumulation in your thyroid. It does nothing against Strontium-90, Cesium-137, inhaled alpha radiation, beta particles, neutron radiation, gamma radiation.

Again, some silver-lining: the Japanese already have a diet rich in iodine because they eat so much fish and seaweed!

[Edited on 3-18-11 by DDTea]

Sedit - 17-3-2011 at 18:06

My question is why does the body absorb Strontium or Cesium for that matter if its worthless, is there some hidden use for these trace minerals that we haven't fully understood?

Has there been studys on the form of cancer either the Strontium or the Cesium can cause? If so it could be a huge breakthru in study of radioactive waste and cancer causes.

I agree with Entropy on this one, Nuke power is far and wide the safest aside from perhaps solar or wind. All the rest including hydroelectric has killed thousands.

madscientist - 17-3-2011 at 19:02

Sedit, I believe cesium is similar enough to potassium, and strontium similar enough to calcium, to be absorbed and retained.

Quote:

They didn't design a plant that could deal with flooding. And then they built it in a place susceptible to tsunamis and hurricanes, both of which cause flooding. What part of this is responsible? Nuclear power plants should not be constructed in such places when they are unwilling or unable to prepare for contingencies!

If it happens once in 1000 years, it needs to be taken into account. The ravaging of New Orleans by Hurricane Katrina serves as a case study of what can happen when you only plan on a 100 year timescale. The Dutch built levees to protect Amsterdam from a 10,000 year flood. Flood damage doesn't last for 10,000 years. Radioactive contamination does.

<a href=http://www.telegraph.co.uk/news/worldnews/wikileaks/8384059/Japan-earthquake-Japan-warned-over-nuclear-plants-WikiLeaks-cables-show.html>The Fukushima plant was not designed to withstand a 7.9, but only a 7.0. The dangers facing Japanese nuclear power plants were well known.</a>

<a href=http://www.bloomberg.com/news/2011-03-15/ge-staff-quit-in-1970s-over-design-in-japan-reactor-abc-says.html>Additionally, problems with the containment vessel design were well known almost 40 years ago.</a>

<a href=http://blogs.abcnews.com/politicalpunch/2011/03/japan-events-leading-up-to-the-fukushima-nuclear-disaster.html>Harold Denton of the NRC was quoted by the New York Times in the 1980s stating that the containment vessel had a 90% chance of failure in the event of a serious accident.</a>

<a href=http://www.google.com/hostednews/ap/article/ALeqM5iU29-CtBza8xA01r9IzPwksyP1WQ?docId=9e518d4998224fd8b705cc3fe9903eb6>The whole business is plagued with corruption, cover-ups, and cutting corners on safety.</a>

Quote:

In 1989 Sugaoka received an order that horrified him: edit out footage showing cracks in plant steam pipes in video being submitted to regulators.

As far as deaths go outside of acute radiation poisoning, it's common knowledge they happen - cancer! Are you really claiming a radioactive cloud that floated over much of Europe didn't cause cancer? People in Europe weren't taking iodide to treat radiation sickness, it was to prevent thyroid cancer.

<a href=http://www.wiley.com/WileyCDA/WileyTitle/productCd-1573317578.html>Here's the book that estimated the death toll at nearly a million.</a>

<a href=http://www.who.int/mediacentre/factsheets/fs303/en/index.html>From the WHO itself:</a>

Quote:

Although there is controversy about the magnitude of the cancer risk from exposure to low doses of radiation, the US National Academy of Sciences BEIR VII Committee, published in 2006, a comprehensive review of the scientific evidence, and concluded that the risk seems to continue in a linear fashion at lower doses without a threshold (this is called the “linear no-threshold” or LNT model). However, there are uncertainties concerning the magnitude of the effect, particularly at doses much lower than about 100 mSv.
The Expert Group concluded that there may be up to 4 000 additional cancer deaths among the three highest exposed groups over their lifetime (240 000 liquidators; 116 000 evacuees and the 270 000 residents of the SCZs). Since more than 120 000 people in these three groups may eventually die of cancer, the additional cancer deaths from radiation exposure correspond to 3-4% above the normal incidence of cancers from all causes.

<a href=http://www.sciencedaily.com/releases/2007/05/070530080956.htm>Cancer risk rose in Sweden after Chernobyl:</a>

Quote:

The cancer risk increased with rising fallout intensity: up to a 20-percent increase in the highest of six categories. This means that 3.8 percent of the cancer cases up to 1999 can be ascribed to the fallout.

<a href=http://www.independent.co.uk/environment/chernobyl-still-causing-cancer-in-british-children-475263.html>Cancer rates jumped in Britain after the disaster and remain elevated:</a>

Quote:

More than a third of Britain is still contaminated by radioactivity from the Chernobyl disaster two decades ago, and children are getting cancer as a result, an Independent on Sunday investigation has established.
...
And scientists have found rates of thyroid cancer in children in Cumbria, the worst-affected part of England, rose 12-fold after the catastrophe - and blame fallout from the radioactive cloud that spread from the stricken reactor. This confounds government assurances at the time that the radiation in Britain was "nowhere near the levels at which there is any hazard to health".

<a href=http://www.nih.gov/news/health/mar2011/nci-17.htm>The NIH writes on the still elevated risk of thyroid cancer due to Chernobyl.</a>

<a href=http://www.cancer.fi/syoparekisteri/en/research/breast-cancer-in-areas-with-high/>The Finnish Cancer Registry writes on elevated risk of breast cancer in contaminated parts of Belarus and Ukraine:</a>
(A mention of the incubation period is highlighted.)

Quote:

Our study demonstrated increases in breast cancer incidence in all areas following the Chernobyl accident, reflecting improvements in cancer diagnosis and registration. In addition, a significant two-fold increase in risk was observed, during the period 1997-2001, in the most contaminated districts (average cumulative dose of 40.0 mSv or more) compared to the least contaminated districts (RR in Belarus 2.24, 95% CI 1.51-3.32 and in Ukraine 1.78, 95% CI 1.08-2.93). The increase appeared approximately 10 years after the accident, was highest among women who were younger at the time of exposure and was observed for both localised and metastatic diseases.

<a href=http://ije.oxfordjournals.org/content/30/1/125.full>A paper published in The International Journal of Epidemiology on the subject of leukemia:</a>

Quote:

An observed increase in leukaemia cases in Belarus was reported for the 7-year period following the Chernobyl accident.8 Rates were 1.2 times higher after the accident compared to the pre-accident period among the population living in territories with a level of radioactive pollution exceeding 555 kBq per m2.

As far as the Three Mile Island studies go, as stated by the WHO, it is virtually impossible to know whether a cancer death resulted from fallout or from other causes. It can only be proven when it becomes such a big phenomenon that it can be identified in the broad population with statistical methods. The Three Mile Island incident involved a comparatively minor release of radiation, so any cancer deaths that resulted would be virtually impossible to identify.

Also, don't forget that coal isn't the only energy source that has to be mined. Uranium mining isn't a happy business.

DDTea - 17-3-2011 at 19:41

The body has so many uses for trace metals: nerve transmissions, transport, biological catalysis/enzymatic reactions, etc. When unstable isotopes of these metals are incorporated into the body, radioactive decay destroys biological molecules near the isotope. This is especially dangerous if it damages DNA in just the right way to prevent cell-death or to cause mutations. Also, while alpha radiation is a very minor risk outside the body, it is extremely dangerous inside the body for the reasons mentioned. The same applies to beta particles while gamma is dangerous no matter where it is.

Iodine-131, strontium-90, and cesium-137 are some of the more dangerous isotopes present in nuclear fallout.

Taken from the following PDF: www.evs.anl.gov/pub/doc/Cesium.pdf

Quote:

After being taken in, cesium behaves in a manner similar to potassium and distributes
uniformly throughout the body. Gastrointestinal absorption from food or water is the principal source of
internally deposited cesium in the general population. Essentially all cesium that is ingested is absorbed into
the bloodstream through the intestines. Cesium tends to concentrate in muscles because of their relatively
large mass. Like potassium, cesium is excreted from the body fairly quickly. In an adult, 10% is excreted
with a biological half-life of 2 days, and the rest leaves the body with a biological half-life of 110 days.
Clearance from the body is somewhat quicker for children and adolescents. This means that if someone is
exposed to radioactive cesium and the source of exposure is removed, much of the cesium will readily clear
the body along the normal pathways for potassium excretion within several months.

Additionally:

Quote:

While in the body, cesium poses a health hazard from both beta and gamma
radiation, and the main health concern is associated with the increased likelihood for inducing cancer.

Regarding strontium from http://en.wikipedia.org/wiki/Strontium#Effect_on_the_human_b... :

Quote:

The human body absorbs strontium as if it were calcium. Due to the elements being sufficiently similar chemically, the stable forms of strontium might not pose a significant health threat—in fact, the levels found naturally may actually be beneficial (see below) -- but the radioactive 90Sr can lead to various bone disorders and diseases, including bone cancer. The strontium unit is used in measuring radioactivity from absorbed 90Sr.

Regolith - 18-3-2011 at 06:32

Madscientist, Your opinion seems to be not that nuclear is bad, it's rather when we keep doing it wrong that's bad?

They did screw this up... The building itself was built to code (at the time). Once reactors go online they are usually grandfathered into regulations etc at that time. Adding to that nuclear reactors can't be moved or changed really once first criticality is achieved.

NHK live was showing pictures of this area that looks like a dock where the generators were. My initiall understanding was the generators were in a safe location(and there was MORE than ONE), near the reactors not this loading area they showed still underwater. I still believe in nuclear power, but I mean we don't have redundancy for the "if it fails, all is lost" backup generator? One single point of failure before totally screwed. Reactors like all massive power stations can't self energize so they can't run one reactor for power and power themselves. They had no plan after there one diesel went down..

quicksilver - 18-3-2011 at 08:01

Quote: Originally posted by hissingnoise

I agree qs, hindsight is a great thing but we all know that the designers of the plant had at the time believed that the chances of a 'quake occurring at the magnitude of the one that hit were so vanishingly small that safeguarding against such a scenario would have looked like expensive overkill . . .

I'm not totally convinced that there wasn't a few "hold-outs" in Japan; fearing that the island group as a whole was just too unstable.
.....We will probably never know. But they get a hell of a lot of quakes and unfortunately one cannot isolate the plant enough to make it both financially feasible & give enough distance to limit immediate & total disruption.
Perhaps there are places that simply should look to alternatives if they are in a geological location with that type of risk?
It seemed like a no-win choice in that if they didn't have that power they could not have risen to the height of economic growth their potential demanded...... I certainly agree that it's a damn shame & their stoicism is unique in history.

entropy51 - 18-3-2011 at 09:23

Quote: Originally posted by madscientist

This report on Chernobyl's Legacy by the UN, WHO, UNSCEAR, IAEA etc. states that claims of deaths numbering even in the tens of thousands are exaggerated. Increasing cancer rates all over Europe does not prove causality as I'm sure you know. Cancer rates have been increasing all over the world for many decades now. You might as well blame radiation emitted by cell phones as Chernobyl.

Quote: Originally posted by madscientist

There is no way to know that a particular cancer was caused by radiation. Cancers caused by radiation are not different in any biological way from other cancers. If you have radation dose data for a population, and you never do, you can sometimes show that they are associated with radiation exposure, but not causality. Epidemiology studies never prove causality.

Quote: Originally posted by madscientist

The Three Mile Island incident involved a comparatively minor release of radiation, so any cancer deaths that resulted would be virtually impossible to identify.

I'm shocked that you concede that Three Mile Island was not a public health catastrophe. Thank you.

Be afraid

The WiZard is In - 18-3-2011 at 10:16

very afraid!

hissingnoise - 18-3-2011 at 10:55

WiZ, I think the frivolous tone sounds a bit off, here . . .

Rosco Bodine - 18-3-2011 at 11:02

Looking on the bright side, Japan should have no need anymore for street lights at night when everywhere, everything and everybody, is glowing in the dark.

madscientist - 18-3-2011 at 11:20

Look at the sources I cited. The rises in cancer rates were strongly correlated with the timing of the accident, manifesting in areas that received fallout. Denying that this constitutes strong evidence that fallout causes cancer is absurd. Even the IAEA estimated that 4000 people died as the result of the accident, mostly from cancer.

Take a look at <a href=http://www.wiley.com/WileyCDA/WileyTitle/productCd-1573317578.html>Chernobyl: Consequences of the Catastrophe for People and the Environment</a> before dismissing it. If you live near a university, I imagine the library would likely have a copy. Alexey Yablokov was the environmental advisor to Yeltsin and advisor to Gorbachev. Vassili Nesterenko was the director of the Institute of Nuclear Physics of Minsk, and assisted directly in the liquidation efforts at Chernobyl, suffering great harm to his personal health.

The studies funded by the UN (or whoever doled out the dollars - I don't know offhand) should, as with any literature, be read critically. Patents are a common example that we all know to exaggerate advantages while minimizing or even failing to mention problems. These same issues appear in the scientific literature, and are particularly acute with matters so politicized as the correlation between radiation and cancer. Nuclear weapons and nuclear energy are big issues to big governments and big money, and their influence on research is of course substantial.

Quote:

I'm shocked that you concede that Three Mile Island was not a public health catastrophe. Thank you.

I'm not the one that brought up Three Mile Island, and I never said I had any evidence it caused deaths. Are you going to concede that the fallout from Chernobyl caused more than 28 deaths?

entropy51 - 18-3-2011 at 12:13

Quote: Originally posted by madscientist

I'm not the one that brought up Three Mile Island, and I never said I had any evidence it caused deaths. Are you going to concede that the fallout from Chernobyl caused more than 28 deaths?

I do. I had no problem with the 4000 you cited, only the 1 million.

I brought up Three Mile Island because it is a better example of an accident in a commercial power plant than is Chernobyl, which you brought up.

But Chernobyl is to nuclear power as meth labs are to chemistry: not exactly representative.

bfesser - 18-3-2011 at 12:29

I have just one more asinine comment:

Perhaps they should have invested in developing <a href="http://en.wikipedia.org/wiki/Wave_power">wave power</a> rather than nuclear.

[Edited on 3/18/11 by bfesser]

quicksilver - 18-3-2011 at 12:57

Quote: Originally posted by bfesser

I have just one more asinine comment:

Perhaps they should have invested in developing <a href="http://en.wikipedia.org/wiki/Wave_power">wave power</a> rather than nuclear.

THAT is basically one of the most difficult problems: the DEVELOPMENT. The functionality of the nuke concept existed; therefore the capital and risk associated w/ failure was set aside in favor of a "sure thing". But with every "sure thing" there is always a temptation to go further.
I have no way of knowing IF nuke power could have been developed safely in a quake zone of that magnitude but it seems like attempting to draw to a straight flush when you have 2 pair already.

The WiZard is In - 18-3-2011 at 13:11

Quote: Originally posted by bfesser

I have just one more asinine comment:

Perhaps they should have invested in developing <a href="http://en.wikipedia.org/wiki/Wave_power">wave power</a> rather than nuclear.

[Edited on 3/18/11 by bfesser]

Sorry. The Econut's are opposed to wave power, wind power,
solar, bio-mass..... &c.

The Econut's in Arizona couple back held their breath until
they turned blue ... pissed and moaned 'bout plans to
build an oil refinery... to close to the city — pollution
hazard/explosion hazard. The refinery people gave in and
agreed to move the plant further from the city. The Econuts
held their breath ....&c. Why? Now the plant was toooo far from the city.

Then came the Native Americans. Those mountains 40 miles
from the plant... they are our Sacred Mountains you can't build you
plant there.

The lowlife's who I have an undying hatred for - Green Peace
want the element chlorine banned.....!

"Crime wouldn't pay if the government ran it," reality if
the Econut's ran it.

Or as the guy from Lizard Lick Towing sez - That the problem
with the country — To many freaks and not enough circuses.

djh
-----
Problem is, "Thus shall not kill
whales" ranks among the top
commandments in the cannon
of political correctness. So when
the Makan Indian Nation speared
a whale off America's coast on
Monday, the environmentalists
practically choked on their granola
bars. But pity the animal lovers, for
this is no clear cut call. To the
average activist, interfering in
native American cultures is almost
as taboo as chopping down redwood
trees.

Wall Street Journal 20V99

Polverone - 18-3-2011 at 13:26

Greenpeace claims many more eventual Chernobyl deaths than the World Health Organization, 93000 vs. 4000. Even if you accept that much higher number, it is no proof that nuclear is worse than the status quo. Greenpeace also estimates that fine particulates from American fossil fuel plants kill 30000 people a year. "Safe and normal" operation of American fossil fuel power is equivalent to multiple Chernobyls per decade, by Greenpeace's own numbers. WHO has different numbers but also estimates that combustion particulate deaths dwarf nuclear deaths. Whether you want to use the numbers of mainstream health organizations or of environmental activists, the comparison is similar: fossil fuel waste products kill far more people than nuclear waste products, even after normalizing to deaths per terawatt hour.

I think that nuclear power is the best (or least bad) option for a lot of energy needs now and in the foreseeable future. To change my support at least one of three things would be needed:

1) Nuclear proves a lot more dangerous. This would mean, for example, excess human morbidity and mortality per terawatt hour comparable to that expected from currently operating coal plants.

2) Non-fossil, non-nuclear energy demonstrates real ability to retire coal. X gigawatts of new solar/wind/wave generating capacity come along and replace Y gigawatts of coal capacity, where X is no more than a small multiple of Y. This requires affordable large scale energy storage as well as affordable generation capacity. Solar panels without storage cannot retire coal plants even if they’re very efficient and very inexpensive. Geothermal and hydroelectric power can substitute for coal, but many regions lack those options.

3) The scale of industrial civilization declines dramatically, so our power choices don’t affect the world and the future very much. If the USA had only 30 million people they could all burn coal and it wouldn't mean much in the long term. The dramatic decline of industry, prosperity, and population in the former Soviet Union in the 1990s shows how this could happen in a small way. It also shows that only misanthropes can embrace it as a solution.

The long term waste problem of nuclear power should not be ignored, but neither should the long term waste problems of its fossil competitors. Actinides and technetium from nuclear power last a long time; mercury and arsenic from coal last forever. I don’t object to increased nuclear safety standards but I will be very unhappy if the quest for improved nuclear safety promotes objectively worse fossil-combustion competitors.

hissingnoise - 18-3-2011 at 13:46

Quote:

Perhaps they should have invested in developing <a href="http://en.wikipedia.org/wiki/Wave_power">wave power</a> rather than nuclear.

Too subtle! Unclear . . .

watson.fawkes - 18-3-2011 at 13:50

Quote: Originally posted by The WiZard is In

Sorry. The Econut's are opposed to wave power, wind power, solar, bio-mass..... &c.

Please withdraw the inflammatory language. This thread has remain basically civil to date and we would all benefit if it did not go the way of all flame wars.

Magpie - 18-3-2011 at 15:37

Quote: Originally posted by Polverone

... even after normalizing to deaths per terawatt hour. snip

I think that this is the way that all energy supplies should be compared. It's not rational to be unduly critical of nuclear energy just because most people are ignorant of its technology.

The nuclear industry has been criticized for building plants near the ocean and fault zones. This same logic could be applied to people who chose to live near fault lines and on flood plains near the ocean. I think the death toll in Japan is now at ~ 10,000 and rising because of where they chose to live.

Quote: Originally posted by Polverone

.
3) The scale of industrial civilization declines dramatically, so our power choices don’t affect the world and the future very much. If the USA had only 30 million people they could all burn coal and it wouldn't mean much in the long term. The dramatic decline of industry, prosperity, and population in the former Soviet Union in the 1990s shows how this could happen in a small way. It also shows that only misanthropes can embrace it as a solution.

I actually like this solution alot. Until the world gets its human breeding under control we are going to continue to place a burden on the environment that is increasing exponentially. Many of our crises will (do) have this as the root cause.

The WiZard is In - 18-3-2011 at 15:58

Quote: Originally posted by hissingnoise

WiZ, I think the frivolous tone sounds a bit off, here . . .

Frivolous Mas!?!

Calm down take two quaalude and call me in the morning.

Say ... anyone other then myself remember the murder/suicide
at that US Navy experimental reactor? They had to chop up one
of the sailors and bury parts of him in a hazardous waste site!

djh
----
Being radioactive since being
radioactive wasn't cool.

The WiZard is In - 18-3-2011 at 16:08

Quote: Originally posted by watson.fawkes

Quote: Originally posted by The WiZard is In

Sorry. The Econut's are opposed to wave power, wind power, solar, bio-mass..... &c.

Please withdraw the inflammatory language. This thread has remain basically civil to date and we would all benefit if it did not go the way of all flame wars.

Boooo-hooooo I seem to have violated another Secret
rule here were science is most mad... only Politically Correct
posts are allowed in Legal and Societal Issues. Here truth counts
for nothing.

Polverone - 18-3-2011 at 16:13

For the long term I agree that declining population will mitigate or even solve a lot of problems. Birth rates fall with universal education, and fall even below replacement levels with fairly modest prosperity and stability (the so-called "demographic transition"). For the rest of this century, though, global population is expected to remain higher than it was at century's beginning. If it falls much faster, as in the post-Soviet case, it will almost certainly be due to widespread deprivation and disease rather than increasing choice.

For at least the rest of the century there's going to be a larger population of humans who need energy. It will be late in the 22nd century before global population declines to where it was in my father's childhood, even if the whole world comes to resemble Italy demographically before the 21st is done. I think nuclear power is a pretty good way to provide energy for large populations while minimizing present and future health consequences. I am afraid that this accident will rekindle nuclear resistance for another generation.

madscientist - 18-3-2011 at 22:06

Quote:

Whether you want to use the numbers of mainstream health organizations or of environmental activists, the comparison is similar: fossil fuel waste products kill far more people than nuclear waste products, even after normalizing to deaths per terawatt hour.

This is an important point. The environmental damage from fossil fuels is of course also considerable, as we saw last year during the devastating oil spill in the Gulf of Mexico.

Coal spews smog and ashes directly into the atmosphere, and centuries later, we're still here (though it's obviously caused a great deal of problems). If nuclear plants had done the same with their waste for the last 50 years, I don't think our planet would resemble anything we'd consider habitable. Presently, it is true that coal has done more damage, but the scale of the damage nuclear is capable of is unique. Coal is worse now, but nuclear could prove to be worse later.

Of course, most nuclear waste isn't going to end up blown about and liberally distributed across every continent (barring WWIII or total abandonment of containment efforts), but the potency of its hazards make disposal an intimidating problem. It can't just be buried and abandoned. It can't be launched into space (imagine a Challenger full of plutonium!). It can't be dumped in the ocean (though those who hate seafood may disagree).

We're creating a situation where the only option is to carefully store and monitor everything for longer than civilization has existed - a huge commitment that we may not be able to make. Decommissioned reactors will begin to collapse and leak radiation. Waste containers will break down and do the same. Metals become brittle when irradiated, accelerating these processes. Repairs are difficult, as radiation levels can be high enough to instantly deliver lethal doses, and cause robots to break down. Counting on future technology to solve these problems is a gamble.

A modern example of what we may face is the leaking sarcophagus at the Chernobyl site - it's radioactive enough to prohibit repairs, so a new one, to the tune of over a billion dollars, is having to be constructed off-site and placed over the old one. Imagine a world many years from now where we have hundreds of such sites, as old structures collapse and more catastrophic accidents, such as the one in progress at Fukushima Daiichi, are realized. It's not a pleasant thought.

When all issues are considered, it's clear nuclear energy does not constitute a safe or clean form of "alternative energy." It has caused staggering environmental catastrophes, killed thousands of people, and created an intractable waste problem. We urgently need to move away from fossil fuels and nuclear fuels alike, or our descendants will be hacking and choking as they piss glowing green urine on our graves.

bquirky - 19-3-2011 at 00:52

Im fairly sure all that 'waste' will end up being a valuable commodity at some point.

People will say "wow we had heaps of that stuff but we berried it under a tech-tonic plate"

watson.fawkes - 19-3-2011 at 07:35

Quote: Originally posted by The WiZard is In

Boooo-hooooo I seem to have violated another Secret
rule here were science is most mad... only Politically Correct
posts are allowed in Legal and Societal Issues. Here truth counts
for nothing.

Avoiding inflammatory language has nothing to do with political correctness, and everything to do with human civility. Perhaps if this is a secret to you. It is not, fortunately, to others with strongly held opinions, who have enough respect for other members here to forbear such language.

The WiZard is In - 19-3-2011 at 07:53

Quote: Originally posted by madscientist

When all issues are considered, it's clear nuclear energy does not constitute a safe or clean form of "alternative energy." It has caused staggering environmental catastrophes, killed thousands of people, and created an intractable waste problem. We urgently need to move away from fossil fuels and nuclear fuels alike, or our descendants will be hacking and choking as they piss glowing green urine on our graves.

Thousands of deaths. Forsooth. The credible death
toll for Chernobyl is 59 firemen and workers plus fewer then 15
deaths of children from thyroid cancer.

I would be remiss in not noting that coal mining caused a multitude
of thousands of deaths every year.

an intractable waste problem No. It is only an intractable
political problem not an engineering problem.

The waste depository in Utah was originally required to store
waste for several thousand years. The Econut's complained ..
we went 10 000 years. The Gov spent money by the wheel barrel..
you got your 10 000 years. The Econut's had a sissy fit ... we want
100 000 years. Another ton of money. You got you 100 000 years.
Once again .... we want a million years. More money... you got
you million year guarantee. Three guesses and the first two don' count ... we
want it guaranteed to the end of time! A SL of gov money latter...
sorry no can do. Econut's ... obviously you can't use this facility.

So now in the US of A waste is stored in the worse possible place.. on site.

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