Merged 8.8 quake in Sendai, Japan

[a_unique_person]

That's a big explosion alright, and in a reactor plant too, by the looks of it.

 

[jimbob]

Not exactly. A cubic meter of water weighs 1000 kg which I believe is about 200 pounds more than a ton.

Well, you silly Americans keep referring to a tonne as a "metric ton" which might be the cause of the confusion.

The metric system for length, volume and mass was deliberately related and based on water, hence why a mililitre (cubic centimeter) of water weighs a gram, a litre (cubic decimeter) weighs a kilogram, and a kilolitre (cubic meter) weighs a tonne.

The correlation isn't exact but is pretty close for fresh water at 4 degrees C, and close enough for practical purposes (at 20 degrees C 1 litre of water weighs 0.9971kg).

This may come as a surprise to people who don't use the metric system, but in countries where the metric system is used this is quite common knowledge - something we learn in school as little kids.

It's actually quite useful for determining a very rough ballpark figure for all sorts of things that are predominantly made up of water such as bottles of milk, softdrink bottles, etc.

Actually a UK imperial ton is larger than a metric tonne.

Mind you our pints are 20fl Oz and gallons are 8 of those, so a UK gallon of water is 10lbs.

It is still a silly system. I keep half thinking that as the semiconductor industry is so keen on mixing up microns and thous (mils), that they should start having micro-cubits and nano-cubits as units of length.

 

[Puppycow]

Damn. This is a nightmare.

I just left to stock up on supplies and saw this upon coming back.

 

[Skeptic Ginger]

The color of the smoke suggests steam.

What are they saying on the video?

 

[Sword_Of_Truth]

The color of the smoke suggests steam.

There's virtually nothing else at a nuclear plant that can cause a large explosion.

There aren't large stockpiles of flammable materials like at fossil fuel plants and you just... simply... can't... have a nuclear explosion at a nuclear power plant.

The space between atoms of fissile material in reactor fuel is too great to allow the rapid reaction necessary for a nuclear explosion.

 

[GlennB]

Later shots of the site show the outside of that leftmost building reduced to a metal frame, presumably after the lightweight(??) outer skin was blown off. The metal frame looks intact. I have no idea what this means for the reactor itself, but the initial flash from the blast was pretty big. Amazingly CNNi , Al-Jaz and BBC World switched to scheduled programmes.

 

[Puppycow]

The color of the smoke suggests steam.

What are they saying on the video?

Several things, but one thing they said is that there were reports of radiation 20 times greater than normal, and another thing is that the explosion happened as they were taking action to release the pressure.

 

[Orphia Nay]

I gather the reactor is 150 miles north of Tokyo.

It's a fair way, but not far enough for me not to worry about you, Puppycow, let alone all the millions of people closer to it.

 

[Skwinty]

There's virtually nothing else at a nuclear plant that can cause a large explosion.

If the fuel elements are melting then a large amount of hydrogen would be produced.

If it was a containment building that exploded, could not have been built to the same standards as the PWR containment.

There aren't large stockpiles of flammable materials like at fossil fuel plants and you just... simply... can't... have a nuclear explosion at a nuclear power plant.

Yes, the most explosive it would be is equivalent to a damp squib.

 

[manofthesea]

Officials said six miles away is safe. No need to worry.

Is Fox News pandering to the coal industry yet?

 

[Puppycow]

Here, Rolfe;

http://www.dailymail.co.uk/news/art...rown-sleepy-coast-town.html?ito=feeds-newsxml

Here's the video those stills were taken from:
http://www.bbc.co.uk/news/world-asia-pacific-12717863

 

[Skeptic Ginger]

There's virtually nothing else at a nuclear plant that can cause a large explosion.
...

The BBC suggests hydrogen could be involved. In the close up of the explosion in the video you can see a shockwave that looks like something flammable.

 

[Puppycow]

They say the wind is blowing inland atm, but will change to blow out to sea after nightfall.

 

[Sword_Of_Truth]

Later shots of the site show the outside of that leftmost building reduced to a metal frame, presumably after the lightweight(??) outer skin was blown off. The metal frame looks intact.

That doesn't sound like the reactor containment vessel, the building that actually houses the core itself.

Containment vessels are 6 foot thick steel reinforced concrete domes that cover the entire reactor core along with several subsystems. It doesn't have a "frame" per se, it is woven throughout with steel rebar.

Performance of a section of reactor containment vessel under high stress conditions can be seen in this famous video from Sandia National Laboratories:


Chernobyl did not have a containment vessel like reactors in the west do and there is some discussion among nuclear engineers of whether the Chernobyl blast could have breached a western containment vessel. I do not believe the explosion we witnessed was the containment vessel. But if it was... then we have a situation in Japan that is far worse than Chernobyl.

 

[Rolfe]

They seem to have stopped giving these ridiculous death toll figures though. Saying 29 dead, or "the death toll has been raised to 45" and so on was pretty silly when we could all see the massive extent of the destruction. Even figures in the hundreds re obviously unrealistic. This is going to be in the tens of thousands, at least.

ETA: "At least 1,300" is now being broadcast. Would that it were so few.

Rolfe.

 

[Skwinty]

That doesn't sound like the reactor containment vessel, the building that actually houses the core itself.

If you look at the footage and photo's of Fukishima, it does not appear to have the usual concrete dome structures.

there is some discussion among nuclear engineers of whether the Chernobyl blast could have breached a western containment vessel. I do not believe the explosion we witnessed was the containment vessel. But if it was... then we have a situation in Japan that is far worse than Chernobyl.

3 mile island containment coped pretty well with a hydrogen explosion.

Why would you say that this would be worse than Chernobyl?

 

[Puppycow]

This video from a helicopter is incredible. The wave just keeps going and going relentlessly swallowing up everything in its path:

http://www.bbc.co.uk/news/world-asia-pacific-12709850

This is a Japanese TV channel's site but it has an amazing video from Kamaishi, yet another seaside town in Iwate.

http://www.news24.jp/articles/2011/03/12/07178020.html
(You have to click the video to start it)

 

[GlennB]

That doesn't sound like the reactor containment vessel, the building that actually houses the core itself.

Containment vessels are 6 foot thick steel reinforced concrete domes that cover the entire reactor core along with several subsystems. It doesn't have a "frame" per se, it is woven throughout with steel rebar.

Yes. This 'frame' that has been exposed is essentially the same size as the white 'cube' that it used to be. i.e. the external, visible-to-the-public walls.

 

[23_Tauri]

Thank you and thank everyone else who had me in their thoughts.

You and all the Japanese people are in my thoughts right now. I am thinking of little else. I cannot imagine what it must be like for you all.

 

[Sword_Of_Truth]

If you look at the footage and photo's of Fukishima, it does not appear to have the usual concrete dome structures.

The guys on my email list are up late tonight. I've asked them what they know about Japans containment vessels. I will relay anything they tell me.

Why would you say that this would be worse than Chernobyl?

Because Chernobyl didn't have a western style containment vessel. I can't speak for US vessels (at least ones other than the one depicted in the Sandia Labs test) or Japanese containment vessels, but I spoke to a member of the original CANDU-6 design team, and for their work, they studied the performance of German coastal fortifications versus 16 inch battleship shells from Allied ships during the Normandy landings.

If there was sufficient energy to do what we observed to a building designed to take better than a barrage from the USS Missouri and keep standing, shredding it completely from the inside out, then we are talking some serious blast energy here.

It would be difficult for a reactor running at full power to do this(Chernobyl experienced a brief burst of 250 times it's normal operating power level just before its blast), let alone one that has been shut down as Fukushima was.

As I said, I do not believe that this was the containment vessel we saw being obliterated.