Merged nuclear power safe?

[MarkCorrigan]

Please have a look at this animation from Dutch television.

It shows what went wrong (loss of coolant, emergency coolant injected), but also shows what would happen in case of a meltdown.

The reactor vessel is on 30 cm thick (according to this news item).
The reactor building has a hole in it.

based on this information, it looks like a meltdown would result in quite lot of radioactive material escaping the building, not just causing a huge molten mess in the reactor vessel as many here claim (if I remember correctly).

Can those in the know enlighten me?

You didn't link the animation, but given how you describe it, there's a serious problem in that the reactor containment vessel is not the reactor building. The containment vessel should hold against a meltdown quite easily, so if it isn't breached, then the hole in the building could be an inch or a metre wide and it wouldn't matter.

 

[Sword_Of_Truth]

Reactor building = reactor vessel?

Sometimes, but not always.

The reactor containment vessel is often naked, but sometimes has a more conventional building constructed around it.

 

[DC]

For what it's worth DC, I don't think you're anti-nuke. I do think that you're convinced that you're right and are stubbornly refusing to back down, despite the evidence provided, but that's more pig-headedness than anti-nuke beliefs.

the point is, there was no EVIDENCE provided. and its only about that one story about not venting into the air to prevent panic, i think thats a huge nonsense. they would not risk damage to the vessels by an explosion just to prevent panic from a radiation peak.

i think this story is BS and he made it up. provide a link to a respected source and i am convinced that they indeed did that. and i will admit that i was wrong. i have several times asked for the link, i have googled for it, but found nothing.

 

[Last of the Fraggles]

That in the event of a major quake the following are entirely probable is not 'every conceivable' type of speculation. Japan is a land just waiting for a major quake, it probably has the toughest building codes in the world.

1. There is a good chance external power will fail. This is a given in a major quake. Don't count on it.
2. There may well be a major tsunami. After the Indonesian tsunami, the protection for the backup generators may well have stood a quick check. Near sea level behind a sea wall would have raised some interest. Don't count any anything near sea level being available.
3. The outages may well last longer than eight hours in the case of a major quake. In a major quake, expect power to be out for protracted periods of time. Modern battery technology has the capability to keep power going much longer.

The power to keep the cooling going is already very vulnerable on all three available sources. Having multiple vulnerable backups doesn't count for much.

It may have sounded good in 1970, but over 40 years, a review would have found that it needed improvement.

There are the containment levels, but by the time you are talking about using them, you are already getting pretty desperate. Having the backup cooling is the first line, and if it had worked, none of the the following disaster would have had to be dealt with.

There is also the issue of why an obsolete power plant was still even in service when there are much more modern, that is failsafe, designs available. A politician on the radio claimed this was due to anti nuclear protests. If it hadn't been for them, the plant would have been replaced already. I don't know how true that is.

If Japan has the toughest building codes in the World (it may do I don't know) then it obviously wasn't enough because the houses fell down. Now using your logic this should have been designed for. Not only that but if we uprate the new designs and building codes we should tear down all the old obsolete house designs and replace them. I think we'd both agree that's a silly idea.

Nuclear power stations have a design life and this one was coming to the end of it. It's not surprising it was neither the best or the safest design nor that it was rendered obsolete by new advancements. However, obviously the decision was taken that the plant was 'safe enough' - maybe based on the fact that even if the worst happened and the power went out and the backups failed you still had physical containment?

Would it hvae been better if the nuclear power plant was a better design? Absolutely. Then again it would have been better if the houses had stayed up, the dams didn't burst, the oil refineries didn't go on fire, the shops didn't run out of TP and media didn't scare people with thoughts of armageddon, nuclear catastrophe, Chernobyl, and massive radiation leakage.

 

[DC]

Not only that, but also because he/she constantly refuses to give any links/sources as well. What good for the goose and all that.

Greetings,

Chris

oh and what claims am i making you want to have backed up`? just ask for it.

 

[Eddie Dane]

You didn't link the animation, but given how you describe it, there's a serious problem in that the reactor containment vessel is not the reactor building. The containment vessel should hold against a meltdown quite easily, so if it isn't breached, then the hole in the building could be an inch or a metre wide and it wouldn't matter.

I've added the link.

It shows the vessel as a Rosanne Barr-shaped container within a geometrical building.

In case of a MD, the fuel rods would melt down to the bottom of the vessel. (according to the animation).

Would the meltdown be contained within the vessel?

The voice-over says that in case of a MD, 'a great quantity of radiation could be released'.

 

[MarkCorrigan]

I've added the link.

It shows the vessel as a Rosanne Barr-shaped container within a geometrical building.

In case of a MD, the fuel rods would melt down to the bottom of the vessel. (according to the animation).

Would the meltdown be contained within the vessel?

Unless it was breeched in some way, yes.

The voice-over says that in case of a MD, 'a great quantity of radiation could be released'.

Not unless the containment vessel is damaged. What, they think that radiation will pass through something designed to stop that exact thing?

 

[timhau]

What, they think that radiation will pass through something designed to stop that exact thing?

More than likely, yes, that's exactly what they think. If Dutch journalists are anything like ours in Finland, the young generation will have a degree in journalism, social sciences, and/or humanities, the older generation will mostly be dropouts. It's highly unlikely that they have received any science education after they left high school/gymnasium.

 

[a_unique_person]

Monday Quater-backing sums up this entire post. All engineering has to consider what risk it is willing to counter, the effects of a 1,000 year earth quake, the 5th largest ever recorded, and then being hit by a 10m high tsunami is pretty unlikely. You might as well ask why the WTC wasn't built to withstand the impact and fires of a high speed 767.

Apparently, that stretch of coast has seen similar tsunamis in 1896 and 1933, so the current tsunami is hardly a 1,000 year event, and should have been catered for.

 

[MarkCorrigan]

More than likely, yes, that's exactly what they think. If Dutch journalists are anything like ours in Finland, the young generation will have a degree in journalism, social sciences, and/or humanities, the older generation will mostly be dropouts. It's highly unlikely that they have received any science education after they left high school/gymnasium.

But *I* have received no formal science education since I did my A-levels, where I took biology, and I haven't done physics since I was 16, 7 years ago. Why is it that I understand basic nuclear physics but reporters who are supposed to be just as educated as me do not?

 

[Last of the Fraggles]

But *I* have received no formal science education since I did my A-levels, where I took biology, and I haven't done physics since I was 16, 7 years ago. Why is it that I understand basic nuclear physics but reporters who are supposed to be just as educated as me do not?

Presumably you have some kind of interest in science and technology though (or you wouldn't be here) whereas many reporters might be of the type who are scared of numbers, flunked their science exams and couldn't care less about the difference between a proton and a Cadbury's Creme Egg.

Given that a lot of reporters seem to struggle with language, grammar, investigation and research, understanding evidence, balancing opposing views (if I give 2 crackpots with opposing ideas 5 minutes each, that's a balanced report, right?!?) and providing informative and interesting reports and other basics of their actual job I think its probably expecting too much of them to have even cursory knowledge of the areas they report in.

A lot of 'journalists' who are reporting on this event were probably providing an indepth expose on Katie Price's knickers or Cheryl Cole's hairdo last week.

 

[a_unique_person]

Nothing is 100% safe. How does it really compare?

How many people died at 3 mile island?
How many people died during the Gulf of Mexico BP accident?

It just seems to me that the damages from oil spills are greater than from the nuke accidents. People are impressed by drama. The Hindenberg put a stop to that kind of air ships for luxury trips. Maybe people are associating the Hiroshima bomb with the Japanese power plant. People are stupid.

The Japanese are still very sensitive about things to do with nuclear reactions. Just saying.

Just because more people died due to the quake and tsunami, doesn't absolve the owners of the nuclear plant from managing it properly. I expect they will be getting some very stern messages from their peers, who will find their nuclear businesses suddenly worth a lot less.

 

[timhau]

Presumably you have some kind of interest in science and technology though (or you wouldn't be here) whereas many reporters might be of the type who are scared of numbers, flunked their science exams and couldn't care less about the difference between a proton and a Cadbury's Creme Egg.

I think you more or less got it. A friend of mine who is a journalist with a master's in history was sent by his paper to a course in election math aimed at newspaper journalists. They had to start by telling the participants how percentages are calculated, and what the difference is between 10 percent and 10 percentage points. And these weren't all kids -- it turns out that many participants had covered several elections without knowing that stuff.

Oh, and I could also tell you about the local MP who was concerned about the pollution in the Baltic Sea and had the bright idea that if all the 8 nations with Baltic shoreline would cut their seabound pollution by 5%, we'd end up with a 40% reduction in yearly pollution (and no, it's not a slip of the tongue, she put this in writing in a newspaper-published opinion piece).

These are the people who inform us and make our decisions.

 

[BenBurch]

Here is my scam idea; We sell people small glass cubes and tell them that they are scintillation glass that will glow when there are dangerous amounts of radiation. Of course they are just cheap lumps of glass. We charge $59.95 and S&H ($25) with a $30 surcharge for express shipping...

 

[Last of the Fraggles]

I think you more or less got it. A friend of mine who is a journalist with a master's in history was sent by his paper to a course in election math aimed at newspaper journalists. They had to start by telling the participants how percentages are calculated, and what the difference is between 10 percent and 10 percentage points. And these weren't all kids -- it turns out that many participants had covered several elections without knowing that stuff.

Oh, and I could also tell you about the local MP who was concerned about the pollution in the Baltic Sea and had the bright idea that if all the 8 nations with Baltic shoreline would cut their seabound pollution by 5%, we'd end up with a 40% reduction in yearly pollution (and no, it's not a slip of the tongue, she put this in writing in a newspaper-published opinion piece).

These are the people who inform us and make our decisions.

The majority of people I have seen offer opinions through the media on the nuclear situation in Japan have belonged to one of a number of groups:

1. Journalists (or what passes for journalists these days)
2. Presenters (the kinds of people who aren't even qualified enough to merit the claim to be journos)
3. Politicians
4. Anti-Nuclear lobbyists (often rather deceptively referred to as nuclear 'experts' or 'analysts')

There's been a distinct lack of actual expertise and understanding of the situation on show and sadly in the few situations where it has been available they've generally been treated to loaded questions, and guided down the path of comparisons to Chernobyl, commenting on how terrified everyone is of radiation and explaining 'worst case scenarios'

I should know better than to read the tabloids (I just buy them for the footbal mostly) but I was informed residents of Tokyo were FLEEING FOR THEIR LIVES as they face the growing THREAT of NUCLEAR RAIN.

 

[MattusMaximus]

So we've basically got the same situation as yesterday, but slightly more dangerous and with a one hour gap when the radiation seriously spiked?

Meh, colour me remarkably unimpressed if that's thee case.

Yes, and I keep seeing/hearing people go on and on about how Fukushima "is now a 6 on the INES", but I can find no confirmation of that beyond some speculation in an article in Germany (which I think has been misrepresented on Wikipedia). The last estimate I saw from the proper authorities is that Fukushima is still a 4 on the INES.

Anyway, if anyone wants to know more on that point, I updated my blog last night about it. Also, if anyone can find actual, reliable confirmation that the INES rating of Fukushima has indeed gone up, I'd like to see it.

 

[MattusMaximus]

Here's an idea. Let's stick DC's goalpost on to a electrical generator. With that speed in which they are moving, we should be able to replace a nuke or two with the power produced. Probably for a very, very long time.

Greetings,

Chris

Here's a better idea: ignore DC and his useless rants.

 

[bobdroege7]

Not unless the containment vessel is damaged. What, they think that radiation will pass through something designed to stop that exact thing?

Sorry that I have to say this, but this is ignorant on several levels.

The containment building is designed to contain the radiation and contamination, but it is a rather large structure with many piping penetrations which are sealed with materials that range from robust to rather flimsy.

I say flimsy because I know what I am talking about having acually sealed such penetrations at a BWR-6 plant simular but probably a bit more robust than the ones in Japan.

A BWR-6 has a drywell and a Containment building rated at 30 and 15 psi, if memory serves.

When you don't have emergency cooling capacity for an extended period of time following a shutdown, the pressure in the reactor vessel rises, until a set pressure is reached, which caused valves to open to relieve that pressure, from the reactor vessel to the containment building. The suppression pool actually, a large pool of water at the bottom of the containment building.

The hydrogen explosions indicate that the containment system is no longer "containing" the core elements.

This is way beyond what the containment system is designed to be able to withstand. The emergency cooling and containment systems are simply not designed to handle this without electrical power.

These systems are designed to prevent a meltdown, not contain one after the fact.

 

[MattusMaximus]

Reactor building = reactor vessel?

No, they are not the same thing. Damage to the reactor building is serious, but damage to the reactor vessel is very, very serious.

 

[Last of the Fraggles]

Yes, and I keep seeing/hearing people go on and on about how Fukushima "is now a 6 on the INES", but I can find no confirmation of that beyond some speculation in an article in Germany (which I think has been misrepresented on Wikipedia). The last estimate I saw from the proper authorities is that Fukushima is still a 4 on the INES.

Anyway, if anyone wants to know more on that point, I updated my blog last night about it. Also, if anyone can find actual, reliable confirmation that the INES rating of Fukushima has indeed gone up, I'd like to see it.

Not being an expert I'm a little concerned that things tend to be appearing to be getting worse rather than better. Shouldn't the cores actually be cooling down?

Hard to tell the real situation with so many conflicting reports going round though.

The BBC saying that the Japanese have increased the 'safe level' for plant workers from 100 to 250 milli sieverts which doesn't sound good to me.