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Nuclear power, clean, safe, too cheap {er… complicated} to meter
Posted: 12 March 2011 07:00 PM   [ Ignore ]   [ # 16 ]
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>>Yes they have. It happened to one of the early ones in the North Atlantic. I can’t remember the name of the sub off the top of my head anymore, but everyone died.<<

You may be thinking of the USS Thresher, which was not a nuclear accident at all, even though the reactor did shut down in the course of the casualty itself. You might find http://www.americanheritage.com/articles/magazine/it/1997/1/1997_1_24.shtml to be useful.

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Posted: 12 March 2011 07:17 PM   [ Ignore ]   [ # 17 ]
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garythehuman - 12 March 2011 02:24 PM

Psi:

Well they are safe when they are not in earthquake zones or designed and controlled by Russians.

And Three Mile Island?

What was the death toll from that?

Maybe we should ban trains and automobiles because of all of the people that died because of them.

What about coal mines?

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Posted: 12 March 2011 07:30 PM   [ Ignore ]   [ # 18 ]
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Equal Opportunity Curmudgeon - 12 March 2011 07:00 PM

>>Yes they have. It happened to one of the early ones in the North Atlantic. I can’t remember the name of the sub off the top of my head anymore, but everyone died.<<

You may be thinking of the USS Thresher, which was not a nuclear accident at all, even though the reactor did shut down in the course of the casualty itself. You might find http://www.americanheritage.com/articles/magazine/it/1997/1/1997_1_24.shtml to be useful.

That is the sub I was trying to remember! Didn’t the reactor fail? Thanks for the link. I’ll check it out. As a child growing up in the military(Navy), I remember that incident. I don’t remember how soon after we learned about it, but we all knew.. downer

[ Edited: 12 March 2011 07:37 PM by asanta ]
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Posted: 12 March 2011 09:23 PM   [ Ignore ]   [ # 19 ]
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After the devastating magnitude 8.9 Japanese earthquake and the subsequent horrendous tsunami, it is really tragic that there could be potential meltdown in 2 nuclear reactors.

From this report
HERE

The explosion at the nuclear plant, Fukushima Dai-ichi, 170 miles (274 kilometres) northeast of Tokyo, appeared to be a consequence of steps taken to prevent a meltdown after the quake and tsunami knocked out power to the plant, crippling the system used to cool fuel rods there.

The blast destroyed the building housing the reactor, but not the reactor itself, which is enveloped by stainless steel 6 inches (15 centimetres) thick.

Inside that superheated steel vessel, water being poured over the fuel rods to cool them formed hydrogen. When officials released some of the hydrogen gas to relieve pressure inside the reactor, the hydrogen apparently reacted with oxygen, either in the air or the cooling water, and caused the explosion.

Desperate measures:

Nuclear agency officials said Japan was injecting seawater into the core — an indication, Hibbs said, of “how serious the problem is and how the Japanese had to resort to unusual and improvised solutions to cool the reactor core.”

Officials declined to say what the temperature was inside the troubled reactor, Unit 1. At 2,200 degrees Fahrenheit (1,200 degrees Celsius), the zirconium casings of the fuel rods can react with the cooling water and create hydrogen. At 4,000 Fahrenheit (2,200 Celsius), the uranium fuel pellets inside the rods start to melt, the beginning of a meltdown.

Some consolation:

Yaroslov Shtrombakh, a Russian nuclear expert, said it was unlikely that the Japanese plant would suffer a meltdown like the one in 1986 at Chornobyl, when a reactor exploded and sent a cloud of radiation over much of Europe. That reactor, unlike the reactor at Fukushima, was not housed in a sealed container.

These boiling water reactors were apparently commissioned in the 70’s. Japan (with hardly any petroleum), has 55 nuclear reactors supplying a third of their energy needs.

In an interview by the BBC with a nuclear specialist, he said they suffered a double whammy. The earthquake and the tsunami crippled the primary and backup power supplies for the cooling system leaving only battery power and no reliable source of water for cooling.

OTOH, from this report HERE

A black swan:

Ken Bergeron, a physicist who formerly worked for Sandia National Laboratories, says a so-called station blackout - which involves the loss of both off-site electricity and on-site backup power from diesel generators - is viewed in the nuclear industry as extremely unlikely.  But he says it happened.

“So we’re in uncharted territory.  We’re in the land where probability says we shouldn’t be.  And we’re hoping that all of the barriers to release of radioactivity will not fail,” he said.

He said the first barrier, the so-called fuel cladding that covers the reactor rods, has apparently failed, which he says is shown by the release of radiation into the atmosphere. 

Crews are pumping a mixture of seawater and boron to cool the reactor, and these experts say it is essential to keep the water flowing for several days.  Analyst Alvarez called the use of seawater a “Hail Mary pass”, a term from American football meaning an act of desperation.  But he said that with enough water pumped at sufficient volume and rate, the reactor can be stabilized.

Complex systems:

Ira Helfand of the group Physicians for Social Responsibility says the reactor contains huge levels of radioactivity that cannot be allowed to escape. “The bottom line is that we just don’t know what’s going to happen over the next couple of days. And frankly, neither do the people who are operating these power plants.  They’re very complex systems that are clearly way out of whack, and whether they’re going to be able to contain the radiation inside the reactors or not, is simply not known at this point,” he said.

Nuclear power is a two-edged sword, but with petroleum as it is, for many countries like Japan or France, is there is no other viable option?

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Posted: 12 March 2011 10:04 PM   [ Ignore ]   [ # 20 ]
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asanta - 12 March 2011 06:45 PM

Yes they have. It happened to one of the early ones in the North Atlantic. I can’t remember the name of the sub off the top of my head anymore, but everyone died.

The navy has reported the loss of two nuke boats, the Thresher in 1963 and the Scorpion in 1968.  The navy says the Scorpion sank due to a torpedo explosion (a hot run?),though the evidence for such is iffy at best, and the Thresher due to a possible ruptured high pressure pipe that caused a short which scrammed the reactor?  Regardless, there is no evidence that either of the reactors had a fault that caused the sinkings, though the loss of power in Thresher would have caused it to sink below crush depth.

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Posted: 13 March 2011 09:33 AM   [ Ignore ]   [ # 21 ]
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>>Didn’t the reactor fail?<<

No, it shut down, just like it was supposed to. In some respects, it was a little too safe. When there was a casualty in the plant, the reactor shut down automatically and that in turn made it impossible to surface the ship.

They did try to blow ballast but the moisture in the compressed air flasks iced up the lines to the ballast tanks. A fact which they were able to verify with a sister ship under refit in a nearby shipyard. Apparantly, they forgot about the problem of adiabatic expansion.

You can read about the USS Scorpion at http://www.navsource.org/archives/08/08589a.htm and if the information here is correct, the initiating event was not a hot run torpedo (The section with the torpedos is intact and there is no evidence of an external explosion.) but a battery explosion.

There have been a lot of lurid conspiracy theories, some of which made the Soviets the Bad Guys in the affiar, some of which blame a hot run torpedo. The reality, as usual, is a bit more mundane, but the mundane can kill you just as dead as the incredible.

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Posted: 13 March 2011 10:43 AM   [ Ignore ]   [ # 22 ]
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kkwan - 12 March 2011 09:23 PM

At 2,200 degrees Fahrenheit (1,200 degrees Celsius), the zirconium casings of the fuel rods can react with the cooling water and create hydrogen. At 4,000 Fahrenheit (2,200 Celsius), the uranium fuel pellets inside the rods start to melt, the beginning of a meltdown.

They only have to keep the temperature below 4,000 Fahrenheit?  That’s all?  Some people have the balls to think that humans can someday control a fusion reaction of over 10,000,000 Kelvin.

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Posted: 13 March 2011 11:07 AM   [ Ignore ]   [ # 23 ]
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kkwan - 12 March 2011 09:23 PM

Nuclear agency officials said Japan was injecting seawater into the core — an indication, Hibbs said, of “how serious the problem is and how the Japanese had to resort to unusual and improvised solutions to cool the reactor core.”

From what I understand, this is a sign that they’ve basically given up on trying to save the reactor, because the water normally used to cool it is super-pure, so that any of the alpha-radiation is absorbed by the water molecules which do not produce another radioactive byproduct in doing so. By injecting seawater, they’re putting lots of elements into the reactor that will produce radioactive byproducts, meaning that the reactor housing will slowly start to build up radioactivity over time, meaning that even once they get their nuclear reaction under control (I think they will; the Japanese are quite resourceful) they’ll have to basically scrap the whole plant.

And don’t forget that there’s also an uncontrolled fire at a petroleum refinery going on right now, and people have had to be evacuated from THAT area as well. Although there’s more fear factor with the nuclear power plants, it’s arguable that the refinery fire is more dangerous.

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Posted: 13 March 2011 11:27 AM   [ Ignore ]   [ # 24 ]
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TromboneAndrew - 13 March 2011 11:07 AM
kkwan - 12 March 2011 09:23 PM

Nuclear agency officials said Japan was injecting seawater into the core — an indication, Hibbs said, of “how serious the problem is and how the Japanese had to resort to unusual and improvised solutions to cool the reactor core.”

From what I understand, this is a sign that they’ve basically given up on trying to save the reactor, because the water normally used to cool it is super-pure, so that any of the alpha-radiation is absorbed by the water molecules which do not produce another radioactive byproduct in doing so. By injecting seawater, they’re putting lots of elements into the reactor that will produce radioactive byproducts, meaning that the reactor housing will slowly start to build up radioactivity over time, meaning that even once they get their nuclear reaction under control (I think they will; the Japanese are quite resourceful) they’ll have to basically scrap the whole plant.

And don’t forget that there’s also an uncontrolled fire at a petroleum refinery going on right now, and people have had to be evacuated from THAT area as well. Although there’s more fear factor with the nuclear power plants, it’s arguable that the refinery fire is more dangerous.

The plant in question is near/over 40 years old.  The injection of salt water is the coup-de-grace, they will be scrapping the reactor at this point.
The water serves two purposes in a BWR, it acts as a neutron moderator (slows down the neutrons so that they can continue to initiate a chain
reaction) and as a method to transfer heat to the turbine/generator assembly.  The refinery fire is, I agree, at least as worrisome as the
problems at the nuke plants.  Refinery fires can burn for days or weeks and the immediate pollution can be horrific.  The Japanese have their hands full, no doubt.

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Posted: 13 March 2011 11:50 AM   [ Ignore ]   [ # 25 ]
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>>They only have to keep the temperature below 4,000 Fahrenheit?  That’s all?  Some people have the balls to think that humans can someday control a fusion reaction of over 10,000,000 Kelvin.<<

Considering how difficult it is to initiate and sustain a controlled fusion reaction, from an engineering standpoint, this may well prove to be a helluva lot easier to accomplish.

Cut off the supply of dueterium or helium 3, and you have no reaction.

With the core of a fission reactor, the fuel rods are inside and aren’t about to go away. There’s no closing a valve or shutting off an injector.

Uncontrolled fusion reactions (Hydrogen bombs) are another matter, but nobody is trying to run a power plant with those things!

Flatten it, yes. But not run it.

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Posted: 13 March 2011 12:02 PM   [ Ignore ]   [ # 26 ]
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I’ve been anti-fission for a long time too, but it just seems that variety is what’s needed now-a-days.  Technology always has trade-off, no solution is ever ideal, like Occam explained.  hmmm  So I see variety as the better answer, so that we minimize the risks of each technology.  The demand for electricity is insular now-a-days, if you build it they will buy it. 

In the early days, institutions generated their own electricity, using their own generators.  I suppose they chose to use centralized electricity because they thought it was cheaper and more convenient.  Industrial sized generators result in industrial sized failures from time to time, that is one of the trade-offs when choosing individual or common generators.  Do you want your generators to be professionally managed, or managed by your neighbor? 

Why can’t the safety measures can’t be built and maintained through-out the life of a fission power plant?  I am very tentative about including fission into the mix, and I would reject it without long-term safety measures.  We know that coal power will pollute the air with particles and even with radiation, fission power might meltdown if there is a catastrophe.

If the Navy hasn’t had a reactor failure, so what would that mean anyway?  Does it mean that a safe fission reactor is one where we throw some men, women, and a fission reactor into a can, submerge it at the bottom of the ocean, and keep them down there for a few months at a time… I guess that’ll ensure safety.  rolleyes  That logic doesn’t pan out well.  If the US Thresher had a reactor failure, then that takes some credibility away from that idea.

Luckily, we have a wide variety of ways to generate electricity, so it is a good societal choice.  The grid is built, so it makes sense to fully utilize its life-cycle.  smile

How is that fusion thread coming along?

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Posted: 13 March 2011 12:18 PM   [ Ignore ]   [ # 27 ]
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>>If the US Thresher had a reactor failure, then that takes some credibility away from that idea.<<

There’s no evidence that she did and no survey of the wreck has been able to show us otherwise. In the end, it boiled down to the failure of a single brazed joint. The reactor was in no way compromised and had they been able to get a faster restart from the SCRAM, we wouldn’t even be talking about this.

Now if it had been a Russian submarine, it would be a very different matter. The industrial safety standards were generally regarded as being a century behind that of the West. What that meant in practice was that they were willing to take greater risks and didn’t mind too much if some of the corpses glowed in the dark and were so irradiated that there was no need for embalming.

A notorious example of this was the casualty with the K-19, (Yes, it’s a real submarine!).

This particular boat had a history of such accidents and was known sarcastically as “Little Hiroshima” to Northern Fleet sailors.

Another example was an accident they had with a type of submarine known in the West as an Alfa. They had some sort of casualty which forced them to shut down the reactor. Since this reactor used a liquid metal coolant (Lead-bismuth, fortunately. They rejected sodium cooled for the same reasons the USA did) this killed the reactor for good since the cooling medium could no longer be melted. They ended up scrapping the boat.

I haven’t seen any information on any fatalities for this one. The Russians don’t like airing their dirty linen in public and even today, “Glasnost” is a term their military doesn’t understand.

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Posted: 13 March 2011 12:40 PM   [ Ignore ]   [ # 28 ]
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Interesting that I heard on NPR this morning a report by a British naval nuclear agency stating that the nuclear power plants in submarines are quite unsafe. 

Occam

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Posted: 13 March 2011 02:36 PM   [ Ignore ]   [ # 29 ]
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Equal Opportunity Curmudgeon - 13 March 2011 09:33 AM

There have been a lot of lurid conspiracy theories, some of which made the Soviets the Bad Guys in the affiar, some of which blame a hot run torpedo. The reality, as usual, is a bit more mundane, but the mundane can kill you just as dead as the incredible.

I’d heard it was a design flaw. I read the site you provided which talks about the flaw.

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Posted: 13 March 2011 07:54 PM   [ Ignore ]   [ # 30 ]
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>>Interesting that I heard on NPR this morning a report by a British naval nuclear agency stating that the nuclear power plants in submarines are quite unsafe.<<

Occam, you might want to check out http://www.guardian.co.uk/world/2011/mar/10/royal-navy-nuclear-submarine-reactor-flaws which specifically identifies British submarines as the ones with the problems.

Regarding the Thresher, there were a number of design flaws which required remediation. The reactor itself just wasn’t effected by the casualty beyond shutting down exactly as it was designed to do.

The problem is that if you can’t restart the beast after the SCRAM, and your ballast air is not demoisturized so that it literally freezes your system to blow ballast and get to the surface….which was exactly what did happen, it just doesn’t matter.

There’s no meltdown to get you but the implosion of the hull is there to ruin your day!

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