Nuclear disaster in Japan and wider Nuclear discussion

[Ferminal]

The nuclear chain reaction was stopped seconds after the earthquake occurred..

Yeh I know that, so Boron is only used to stop an uncontrollable chain reaction?

Late edit: WNN gives me the answer.

this is planned to be followed by addition of boric acid, which is used to inhibit nuclear reactions

 

[python]

Unit No 1 is a BWR-3. It apparently does not have passive pressure release as more recent models do.

i agree with you. it's cobblestones who needs to understand that the actual design of the 40-year old plant may be different from what he thinks it should be.

the passive cooling design features - those not requiring electricity - both for emergency core cooling and containment cooling were introduced way after the fated japanese plant was on line - in the early 90s for a bwr design and mid 90
for a pwr design (AP600. the one i'm well familiar with).

but again, it's a forum, and people have the right to insist that 'should' equals the reality even as the nuclear disaster is staring into our eyes.

edit for clarification:

all bwr designs to some extent have passive pressure suppression arrangements. it's the suppression pool where the drywell space is discharged into. the main differences in old and new designs refer to cooling of the eventual primary containment overpressure and the reliance on the elevation differences (static head) in stead of pumps for water flow.

 

[Cobblestones]

Yeh I know that, so Boron is only used to stop an uncontrollable chain reaction?

Let me put it in different words.

Boron in the coolant does not hurt when your only goal is to shut the reactor down and keep it cool and off. The point of boron is to absorb neutrons. If there are no neutrons, boron is pointless. So, neither does it help really.

There's one reason why boronated water might be needed, and it is scary. If fuel rods are indeed melting, the fuel lava (corium) will accumulate at the bottom of the core, away from the control rods, and this might restart the chain reaction (not very likely, but still a possibility). Boronated water does make sense when the core is in the process of melting or when you expect it to melt. So, if that's what they're planning to do now, it's worse than it was made out to be. It's probably approaching a TMI/Harrisburg type accident.

Also, use of seawater indicates that they've run out of normal cooling water. That indicates that a lot of steam has escaped either through leaks or emergency pressure relief valves.

 

[Cobblestones]

i agree with you. it's cobblestones who needs to understand that the actual design of the 40-year old plant may be different from what he thinks it should be.

the passive cooling design features - those not requiring electricity - both for emergency core cooling and containment cooling were introduced way after the fated japanese plant was on line - in the early 90s for a bwr design and mid 90
for a pwr design (AP600. the one i'm well familiar with).

but again, it's a forum, and people have the right to insist that 'should' equals the reality even as the nuclear disaster is staring into our eyes.

edit for clarification:

all bwr designs to some extent have passive pressure suppression arrangements. it's the suppression pool where the drywell space is discharged into. the main differences in old and new designs refer to cooling of the eventual primary containment overpressure and the reliance on the elevation differences (static head) in stead of pumps for water flow.

python, it's you who has to understand that reactors are constantly retrofitted with added security features. Just because something was built in 1971, doesn't mean that nothing has ever changed. Lessons were learned from TMI, Chernobyl etc. Even old reactors have most of the safety features of new models.

 

[python]

python, it's you who has to understand that reactors are constantly retrofitted with added security features. Just because something was built in 1971, doesn't mean that nothing has ever changed. Lessons were learned from TMI, Chernobyl etc. Even old reactors have most of the safety features of new models.

cobblestone, it's you who asked a question. i took it and attempted to give you an answer on the basis of the actual news at the time - that the emergency diesel generator and the batteries were out of juice - and (still unconfirmed) the reactor containment was destroyed by the explosion.

you continue to have a conversation with yourself even though it should be obvious now that i'm somewhat familiar with the subject. the fact that reactors are being retrofitted has nothing to do with how you want them being retrofitted. the issue is that we are in the middle of a nuclear disaster and instead of theorizing how it should be designed we need to absorb the news and hope that the human loss is minimal.

obviously it's unproductive to address you any longer, and i wont, because you have your own version of reality and it interferes with an open-minded exchange.

 

[Le breton]

..........
There's one reason why boronated water might be needed, and it is scary. If fuel rods are indeed melting,..........
Boronated water does make sense when the core is in the process of melting or when you expect it to melt. So, if that's what they're planning to do now, it's worse than it was made out to be. It's probably approaching a TMI/Harrisburg type accident.
.....

That was my understanding from the comments made by a French expert on France-info (radio) about 6 hours ago, he thought(?) knew(?) that there had been a partial melting of the core.

 

[Cobblestones]

even though it should be obvious now that i'm somewhat familiar

That's the problem right there. Half-baked knowledge.

Yes, I asked a question, you tried to answer it (wrongly) and I pointed out why your answer had to be wrong.

As I said in an earlier post, it seems to be confirmed that it was a hydrogen explosion. So it has nothing to do with overpressure, pressure relief etc. which you seem to ignore.

But as long as you feel 'somewhat familiar' with ... something?
Whatever dude.

 

[hrotha]

I think the anti-nuclear talk is misguided. If this had been a massive oil spill, we'd be talking about human folly and hubris for not replacing fossil fuels fast enough. Fact is, it's taken a huge, massive earthquake to cause trouble, and while we don't know what the consequences will be, it appears the security of the reactor is quite good. Even if it all blows up one second after I submit this post, it's still probably worth it in the big scheme of things.

 

[rhubroma]

I think the anti-nuclear talk is misguided. If this had been a massive oil spill, we'd be talking about human folly and hubris for not replacing fossil fuels fast enough. Fact is, it's taken a huge, massive earthquake to cause trouble, and while we don't know what the consequences will be, it appears the security of the reactor is quite good. Even if it all blows up one second after I submit this post, it's still probably worth it in the big scheme of things.

Ohh, is that all it took?!!! Well that certainly makes us feel better. You sound like the Wizard of Oz telling us not to look at him behind the curtain. So because we have only had this to date (though already after Chernobyl), you think we shouldn't be overly reactionary? We're talking about a potential nuclear disaster and you call for restraint? And it doesn't matter that we have also had oil spills (or if it does, this should be a call to more reflection, not less).

Sorry but the consequences of a nuclear disaster, in terms of the population and environment, are more than enough reason that you don't build in such risky zones. Hubris, consequently, comes into play.

 

[I Watch Cycling In July]

I think the anti-nuclear talk is misguided. If this had been a massive oil spill, we'd be talking about human folly and hubris for not replacing fossil fuels fast enough. Fact is, it's taken a huge, massive earthquake to cause trouble, and while we don't know what the consequences will be, it appears the security of the reactor is quite good. Even if it all blows up one second after I submit this post, it's still probably worth it in the big scheme of things.

It was a massive and terrible earthquake, but I believe the design of the power plant and it's backup systems should have been able to withstand it. Peak ground accelerations were around 25% of the acceleration due to gravity. If you look at the table posted by Escarabajo here, it is obvious that smaller closer earthquakes could also result in similar or worse damage at a local level. The power backup system should not have failed as a result of this earthquake. The fact that it did is worrying.

 

[Le breton]

partial meltdown confirmed

That was my understanding from the comments made by a French expert on France-info (radio) about 6 hours ago, he thought(?) knew(?) that there had been a partial melting of the core.

Naoto Sekimura, a professor at Tokyo University, told NHK, Japan’s public broadcaster, that “only a small portion of the fuel has been melted. But the plant is shut down already, and being cooled down. Most of the fuel is contained in the plant case, so I would like to ask people to be calm.”

 

[krebs303]

Official: 'We see the possibility of a meltdown'
By the CNN Wire Staff
March 12, 2011 6:06 p.m. EST

A meltdown may be under way at one of Fukushima Daiichi's nuclear power reactors in northern Japan, an official with Japan's Nuclear and Industrial Safety Agency told CNN Sunday.

 

[auscyclefan94]

As for any thermal power plant... except open-cycle gas?

3 people reported to have shown in hospital with abnormal radiation levels.

Does anyone know if they are writing the reactors off by flooding them with boronic acid/sea water? Seems like a bit of a "last resort" solution.

Yes that's true but as both require so much water and then the high amount of risk involved with the nuclear plant then I honestly don't see how it is worth it.

 

[flicker]

Official: 'We see the possibility of a meltdown'
By the CNN Wire Staff
March 12, 2011 6:06 p.m. EST

A meltdown may be under way at one of Fukushima Daiichi's nuclear power reactors in northern Japan, an official with Japan's Nuclear and Industrial Safety Agency told CNN Sunday.

Once the meltdown begins it runs its course, right. It just starts going deeper under the earth until it hits ground water, at which point it explodes radiation into the atmosphere.

 

[flicker]

Wow, if a meltdown went 'China Syndrome' and hit an earthquake fault. it go all Krakatoa.

 

[Anonymous]

Wow, if a meltdown went 'China Syndrome' and hit an earthquake fault. it go all Krakatoa.

You know flicker. There are thousands of people there who died, and many are still dying. Please move to another thread for posts like this, because it isn't funny. In fact, it is pretty disrespectful. There is a human in there somewhere. For once, let him make the decisions.

Sincerely,

TFF

 

[flicker]

You know flicker. There are thousands of people there who died, and many are still dying. Please move to another thread for posts like this, because it isn't funny. In fact, it is pretty disrespectful. There is a human in there somewhere. For once, let him make the decisions.

Sincerely,

TFF

Really, a Tsunami wave took 12 hours to hit my coast. How long does radioactive fallout take to blow over here. I am as serious as a heart attack about a melt down, it almost happened in Chernobyl. 11 reactors shut in Japan, for a very good reason.
Meltdown hits an earthquake fault and the picture is not pretty. I am sure it won't there will not be a meltdown. Pumping seawater into reactors will save them.

About Japan I live in the same 'Ring of Fire' and both my great grandparents survived the 06 SF earthquake. We,' California and Japan' live in the same

zone.

So yes I see the fotos of Tokyo and the surronding areas, people are living in the cold, isolated, without water or power or food, trapped alive under concrete. I get it. I put down prayers for them, it is no joke.
Same thing will hit here where I live, only thing is the Tsunami probably won't hit my area as we are sitting in a protected bay.

Lighten up, TFF and think good thoughts for the Island.

 

[Anonymous]

Really, a Tsunami wave took 12 hours to hit my coast. How long does radioactive fallout take to blow over here. I am as serious as a heart attack about a melt down, it almost happened in Chernobyl. 11 reactors shut in Japan, for a very good reason.
Meltdown hits an earthquake fault and the picture is not pretty. I am sure it won't there will not be a meltdown. Pumping seawater into reactors will save them.

About Japan I live in the same 'Ring of Fire' and both my great grandparents survived the 06 SF earthquake. We,' California and Japan' live in the same

zone.

So yes I see the fotos of Tokyo and the surronding areas, people are living in the cold, isolated, without water or power or food, trapped alive under concrete. I get it. I put down prayers for them, it is no joke.
Same thing will hit here where I live, only thing is the Tsunami probably won't hit my area as we are sitting in a protected bay.

Lighten up, TFF and think good thoughts for the Island.

So you won't mind the Godzilla jokes then?

Again I ask, please save the trolling for another thread. It just isn't appropriate now.

 

[Le breton]

Once the meltdown begins it runs its course, right. It just starts going deeper under the earth until it hits ground water, at which point it explodes radiation into the atmosphere.

No
meltdown partial, as of now.
To get into the ground it would first have to go through the steel of the vessel, then through the concrete of the containment building.

Not there yet. And if they cool the core succesfully it won't happen.

 

[mewmewmew13]

Once the meltdown begins it runs its course, right. It just starts going deeper under the earth until it hits ground water, at which point it explodes radiation into the atmosphere.

No. That is a 'hollywood movie' myth and misconception. Do some research. There are many actions and options for controlling this and they are pursuing every concievable venue. Before you holler 'doomsday' check out some of the links that Ferminal provided earlier in this thread....

 

[mewmewmew13]

Here is a simple and concise explanation of basics....
http://www.reuters.com/article/2011/03/12/us-japan-quake-nuclear-us-idUSTRE72B2UN20110312

Again, Ferminal had posted some excellent resource links, in particular the world nuclear news....good update

http://www.world-nuclear-news.org/RS_Battle_to_stabilise_earthquake_reactors_1203111.html

 

[Hugh Januss]

Some of the video I saw showed boats and shipping containers being swept away by the wave and wiping out people and property in their path, maybe we should not build any more of those either.

 

[rhubroma]

New Orleans demonstrated what happens when man thinks he is the master of nature and plans recklessly, or doesn't consider her at all in the name of development and so called progress, which is just myopic.

Though the consequences for such overconfidence between boats and nuclear power plants are on a slightly different scale. Don't you think? Especially when the boats aren't the issue. Bad analogy.

 

[usedtobefast]

It was a massive and terrible earthquake, but I believe the design of the power plant and it's backup systems should have been able to withstand it. Peak ground accelerations were around 25% of the acceleration due to gravity. If you look at the table posted by Escarabajo here, it is obvious that smaller closer earthquakes could also result in similar or worse damage at a local level. The power backup system should not have failed as a result of this earthquake. The fact that it did is worrying.

i agree. i live 27 miles from San Onofre and it is an old facility. i went there for a field trip in school. i thought we would be able to tour the facility...not!
we got to see the visitors center. so lame. like going to Disneyland and all you get to do is see the giftshop. that told me that stuff is bad news. not safe like they used to tell us back then. "clean energy" not so much.

 

[auscyclefan94]

Some of the video I saw showed boats and shipping containers being swept away by the wave and wiping out people and property in their path, maybe we should not build any more of those either.

Nuclear Plants don't cause radioactive waves which could spread over an 80km radius and cause people to possibly have genetic defects and types of cancers in their upcoming lives.