Japan Earthquake: Nuclear Plants at Fukushima Daiichi

In summary: RCIC consists of a series of pumps, valves, and manifolds that allow coolant to be circulated around the reactor pressure vessel in the event of a loss of the main feedwater supply.In summary, the earthquake and tsunami may have caused a loss of coolant at the Fukushima Daiichi NPP, which could lead to a meltdown. The system for cooling the reactor core is designed to kick in in the event of a loss of feedwater, and fortunately this appears not to have happened yet.
  • #2,346
AtomicWombat said:
I have been convinced that the strong vertical blast originated in the primary containment for some time, see:
http://74.86.200.109/showthread.php?p=3192958"
Specifically:
"The explosion last Monday was directed strongly vertically suggesting to me it originated from deep within the containment structure. It clearly carried substantial solid material to a height of 400-500 metres. Whilst I can't be sure this may have been due to a melt-down of the fuel rods in reactor 3. They melted through the reactor floor (1500 Celsius) and fell into the flooded "dry-well" below. This triggered a large steam- zirconium-water-hydrogen explosion. I suspected this not only blew the concrete top off the containment, it also blew most of the reactor contents out of the reactor."

I'm no longer so confident that it shows melt-through of the reactor contents, but I can't find any other explanation for such a directional blast.

I can suggest one: superheated steam & gas blow out the fuel transfer chute into the upper SFP (water already hot, or boiling, rapidly vaporizing the water, and resulting in an upward focused blast out of the SFP, launching the FHM skyward, yanking a fuel rod assembly out of the pool as it shoots upward, then crashing on the north end of bldg 3.

I had thought that the original blast at Bldg 3 is on the SOUTH end of the building. The damage on the north end sends stuff crashing downward. If the blast photo is taken from inland, looking eastward, then the blast is to the right, southward. Two towers bracket Bldg 4, on the blast (south) side of Bldg 3. A large hunk of debris comes down on the north side of Bldg 3. But the more I look, I can't make that orientation fit with the towers. Someone help me here.

http://i306.photobucket.com/albums/nn270/tcups/Picture28.png

http://i306.photobucket.com/albums/nn270/tcups/Top.png

Doesn't this view have to be from the west?
http://i306.photobucket.com/albums/nn270/tcups/Picture28.png
 

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  • #2,347
|Fred said:
with all due respect I think that Gunderson is likely mistaken, Tepco crane felt into the pool , but not that deep. the top of the rod is at least one floor bellow in my opinion.

To me it looks as though the grid Gundersen is referring to as "fuel storage racks" could be rebar net or something similar. It seems to lie on top of the fuel handling bridge, not below it, and even be somewhat twisted on top of the machine at the edge (see attached image).
 

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  • #2,348
TCups said:
The plug is in place, under the crane.

I don't think having the crane collapse on the plug after the explosion implies the plug is in place.
 
  • #2,349
TCUPS, the pictures I showed, that i extracted from the video of explosion at No3, and that you talk about at the end of your post, are viewed FROM WEST (inland) towards EAST (SEA).

To me, the note you added in the thumbnail pic is wrong: the Buiding N°1 is not so far to the left, you can see it (no so well because the top has been damaged) a little bit to the left of building 2. Building 3 is the one with the antenna perfectly aligned with the North West edge of the Building 3.
 
  • #2,350
AtomicWombat said:
I don't think having the crane collapse on the plug after the explosion implies the plug is in place.

Wombat:

Look at the location of the wheels on the side of the rail on the west end of the bldg. That is a reliable reference for where the crane was positioned relative to the structural columns and east-west location of Bldg 3. They are in the middle. The roof fell on top of the crane. The crane is on top of the plug. Now, the plug may be askew -- can't prove it is or is not, but the plug did not, most assuredly blast skyward, straight up, and miss the crane and the center superstructure of the roof.

What think you about the fuel handling machine blasting upward from over the SFP and crashing downward on the north end of Bldg 3?
 
  • #2,351
jlduh said:
TCUPS, the pictures I showed, that i extracted from the video of explosion at No3, and that you talk about at the end of your post, are viewed FROM WEST (inland) towards EAST (SEA).

jlduh

Please reference the picture post, I want to make sure I am getting it right. My problem is the video pictures I extracted, also viewed from the west, and placing the initial explosion to the south DO NOT coincide with the apparent location of the towers. Trying to resolve.

Again, reference your picture post so I can recheck. Thanks.
Look at the photo attachement to my post 2361 above.
 
  • #2,352
I wonder how long it will be before they can bring in large equipment to move debris off the tops of the structures? Nobody will really know the full extent of the damage and what caused the #3 explosion until it is uncovered and cameras can get a better look. I am guessing it will be many months before we get a better idea. I can't imagine the scope of this cleanup with every piece of debris probably being contaminated and in need of a secure burial somewhere.
 
  • #2,353
AntonL said:
First watch this http://www.bbc.co.uk/news/world-asia-pacific-12931413" released by Tepco, showing close up of the mess in unit 4

Now watch http://vimeo.com/21789121" analysing the Tepco crane head view

Is the spent fuel pool severely damaged and empty or part empty?

sfp4.jpg

|Fred said:
with all due respect I think that Gunderson is likely mistaken, Tepco crane felt into the pool , but not that deep. the top of the rod is at least one floor bellow in my opinion.

The HD picture japan-earthquake-2011-3-30-0-50-12 of the full plant view from the south to the nord and previews picture show that we still are on the operating floor. although in normal condition it should be filled .

I'm not sure I'm relieved or disturbed to find the experts having as much difficulty "reading tea leaves" as we are. Does anyone know what is going on?
 

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  • #2,354
TCups said:
Wombat:

Look at the location of the wheels on the side of the rail on the west end of the bldg. That is a reliable reference for where the crane was positioned relative to the structural columns and east-west location of Bldg 3. They are in the middle. The roof fell on top of the crane. The crane is on top of the plug. Now, the plug may be askew -- can't prove it is or is not, but the plug did not, most assuredly blast skyward, straight up, and miss the crane and the center superstructure of the roof.

I don't doubt that the crane now rests on the mouth of the reactor, where the plug is or was. The blast almost certainly hit the crane and lifted it off its rails, only for it to crash back down again on the operating floor. Most of the blast would have passed through the gap between the crane beams and around its sides. The crane is more space than beams.

TCups said:
What think you about the fuel handling machine blasting upward from over the SFP and crashing downward on the north end of Bldg 3?

Yes it's possible. I would want to be confident we have identified the fuel handling machine before trying to work out how it got there.
 
  • #2,355
TCups said:
Doesn't this view have to be from the west?
http://i306.photobucket.com/albums/nn270/tcups/Picture28.png

It's from the south west. The cloud is clearly behind the stack, which is to the west side of the buildings.
 
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  • #2,356
FROM WHERE WAS THE VIDEO OF THE EXPLOSION OF UNIT 3 TAKEN?

I cannot resolve the problem.

Attached are a frame grab from the early part of the video of the explosion of unit 3, a view of the layout of Fukushima Diiachi Units 1-4 (Google Earth), and an edited version of the same image, showing the footprints (1-4) of each reactor building, and the footprints of each of 3 visible towers (A, B, C). Note also, the apparent heights of the "reactor buildings" in the video freeze frame are different.

What angle, taken from the land, would put a tower aligned to the north end of Bldg 3?

What time of day in the northern hemisphere would put the south face of the buildings in shadow?

http://i306.photobucket.com/albums/nn270/tcups/Picture28.png

Here's the video, 11 AM local time, 3/12/2011

http://video.ft.com/v/825918290001/Fukushima-nuclear-plant-explosion
 

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  • #2,357
TCups said:
FROM WHERE WAS THE VIDEO OF THE EXPLOSION OF UNIT 3 TAKEN?

I cannot resolve the problem.

Attached are a frame grab from the early part of the video of the explosion of unit 3, a view of the layout of Fukushima Diiachi Units 1-4 (Google Earth), and an edited version of the same image, showing the footprints (1-4) of each reactor building, and the footprints of each of 3 visible towers (A, B, C). Note also, the apparent heights of the "reactor buildings" in the video freeze frame are different.

What angle, taken from the land, would put a tower aligned to the north end of Bldg 3?

What time of day in the northern hemisphere would put the south face of the buildings in shadow?

http://i306.photobucket.com/albums/nn270/tcups/Picture28.png

SW,SSW

See tower C cast shadow on RB4 south wall from the sea side, so its most def AM. almost exactly like on your Units1-4.jpg

so that would put the initial RB3 explosion on the EAST, or turbine-building side.
 
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  • #2,358
Radical move suggested by Kyodo News:

URGENT: Gov't eyes injecting nitrogen into reactor vessels to prevent blasts

TOKYO, April 1, Kyodo

"The government and Tokyo Electric Power Co. are considering injecting nitrogen into containment vessels of the Fukushima Daiichi nuclear power plant's reactors to prevent hydrogen explosions, government sources said Friday."

http://english.kyodonews.jp/news/2011/04/82625.html
 
  • #2,359
TCups said:
What time of day in the northern hemisphere would put the south face of the buildings in shadow?

Morning, or very late afternoon to evening. Here's a plot of sunrise/sunset positions for the day #3 exploded.
 

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  • #2,360
caption contest :(
Crane Crane, reactor open lid ?

What's the crane on the right (north) doing there ?
 

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  • #2,361
timeasterday said:
Looks like very late afternoon to evening. Here's a plot of sunrise/sunset positions for the day #3 exploded.
id still say AM, looking at the casted shadows.
 
  • #2,362
Bodge said:
Radical move suggested by Kyodo News:
"The government and Tokyo Electric Power Co. are considering injecting nitrogen into containment vessels of the Fukushima Daiichi nuclear power plant's reactors to prevent hydrogen explosions, government sources said Friday."

The containment vessel are filled with nitrogen in normal time.. providing our understanding of tepco material is correct, rect 1 and 3 were filled with water, there for this concerns only Reactor 2.
 
  • #2,363
hoyrylollaaja said:
SW,SSW

See tower C cast shadow on RB4 south wall from the sea side, so its most def AM. almost exactly like on your Units1-4.jpg

so that would put the initial RB3 explosion on the EAST, or turbine-building side.

And this would put the filmer/newscrew on top of some building at Haramachiku.
 
  • #2,364
hoyrylollaaja said:
id still say AM, looking at the casted shadows.

After looking a bit closer at the explosion photos I think the south side is illuminated, not in shadow. I don't know the exact time of the explosion but I am sure it is documented somewhere.
 
  • #2,366
Bodge said:
URGENT: Gov't eyes injecting nitrogen into reactor vessels to prevent blasts

Makes sense, since hydrogen has been produced, and it has probably no route to escape from the very top of the RPV of the containment. On the other hand, non-deaerated water has been pumped in (first seawater, then freshwater), and calculating from the solubility of gases in the water at different temperatures, this could theoretically result into more than 10 kg of oxygen being released from the water first into the reactor vessel and from there into the containment, eventually diluting the nitrogen atmosphere - if there even is any nitrogen atmosphere left in the containment after the continuous venting during the past three weeks.
 
  • #2,368
On the subject of the radionuclide analyses. Post above indicated that apparently the reanalysis shows that while some of the numbers are gibberish, TEPCO stands behind the I 131 numbers. If this is the case, and the Cs137 numbers are also correct, an interesting conclusion can be drawn.

If you convert the Bq cm-3 readings into numbers of particles you find that the ratio of Cs137: I 131 is about 12,000 : 1. The fission yield data that I've got from Wikipedia (*shrug* reasonable place to start) suggests that the ratio of Cs137:I 131 yields is about 2.15:1. Given their different half lives and assuming that the activity of a fuel rod drops linearly over time (ok, dubious, but it's probably a fair estimate) then you get this sort of ratio right at the end of the life of the rod.

In other words, these sort of readings are appropriate with spent fuel. Wouldn't be appropriate, even after 2 weeks, with live fuel (assuming that the average age of all the rods is half the rod lifespan).

On a related note found an interesting article in the IEEJ: Apr 2008 ("Impacts on International Energy Market of Unplanned Shutdown of Kashiwazaki-Kariwa", Murukami, Watanabe et al) that looked at the shutdown of TEPCOs Kashiwazaki-Karima nukes following the 2007 Niigata quake. The reactors successfully shut down and remained intact despite floor accelerations much higher than design (3x horizontal in reactor 2). So ... kudos to the engineers.

But...

Water leaks into the sea from the spent fuel pond "TEPCO has explained that water flew out of the spent fuel pool to the operating floor on the quake and leaked to the non-controlled area through the fuel exchanger cable and through the wall separating the radiation controlled area from the non-controlled area"

Plus ca change ...

I 131, 133, Co 60, Cr 51 released into main venting stack. Apparently got there from the condenser as the ventilator didn't shut down properly.
 
  • #2,369
Concerning the orientation of the frames from the video of N°3 explosion:

http://www.netimago.com/image_184705.html

There are THREE stacks ("antennas) in this area, two have on vent and one has multiple vents. the one which has multiple vent is on the very South side of the plant, after No4 building. Then there is one "antenna" in between 1-2, AND 3-4 reactors, on the west side oh them (inland). So based on this fact, the video is showing the 3-4 antenna at the the north west edge of building 3 and is seen from SOUTH/SOUTH WEST TOWARDS NORTH/ NORTH EAST.

Do you agree with that?

EDIT: DAMN TCUPS YOU ARE RIGHT! THE ANTENNA IS NOT AT THE NORTH WEST SIDE OF THE BUILDING No3, IT IS AT THE SOUTH WEST EDGE OF IT! The illuminated white side is the SOUTH side of course, not the west side...

Optical illusion!

That ruins all my explanations so far... but that's not important, we have now materail to reassess everything!

Clever eyes you have TCUPS!
 
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  • #2,370
THE BLAST AT BLDG 3

OK, this fits. The fuel handling machine went ballistic.

The camera angle for the video is from the south-southwest (green arrow).

The blast is from the southeast corner (over the SFP3)

The large heavy debris in the video does a back flip over the tower, coming down to the left of the tower, and smacking the north west corner of Bldg 3.

I again propose that the heavy debris was the green fuel handling machine, and I cannot dismiss that if it were hooked onto a single spent fuel rod assembly that was in the process of being uploaded for dry cask storage when the quake hit, that the FHM it took one with it on its ballistic trajectory (dark green parabola).

Refute it!

here is the video again

http://video.ft.com/v/825918290001/Fukushima-nuclear-plant-explosion

And here is a shot showing the direction of the wind after the blast, which also fits.

https://www.physicsforums.com/attachment.php?attachmentid=33860&d=1301658258
 

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  • #2,371
|Fred said:
caption contest :(
Crane Crane, reactor open lid ?

What's the crane on the right (north) doing there ?

Please guys - next I am going to ask what is this brick doing here
 
  • #2,372
Bodge said:
Radical move suggested by Kyodo News:

URGENT: Gov't eyes injecting nitrogen into reactor vessels to prevent blasts

TOKYO, April 1, Kyodo

"The government and Tokyo Electric Power Co. are considering injecting nitrogen into containment vessels of the Fukushima Daiichi nuclear power plant's reactors to prevent hydrogen explosions, government sources said Friday."

http://english.kyodonews.jp/news/2011/04/82625.html

considering the situation it does not make sense, the N2 will only replace steam, and future steam from RV will replace N2 ...
 
  • #2,373
AntonL said:
Please guys - next I am going to ask what is this brick doing here

Sorry, Anton. I can't follow easily if you don't reference the picture you are referring to. Which post number of Freds? Copy the link to the "bricks" photo?
 
  • #2,374
TCups said:
Sorry, Anton. I can't follow easily if you don't reference the picture you are referring to. Which post number of Freds? Copy the link to the "bricks" photo?

I think that he is saying "stop it guys with all the speculation and photo examinations."

I have a headache from looking at all this stuff over the past week and am done squinting at photos until more info comes out. Until someone gets some eyes up close to this stuff (camera/robot eyes preferred) we can just go on speculating forever and not accomplish much.
 
  • #2,375
TCups said:
THE BLAST AT BLDG 3

OK, this fits. The fuel handling machine went ballistic.

The camera angle for the video is from the south-southwest (green arrow).

The blast is from the southeast corner (over the SFP3)

The large heavy debris in the video does a back flip over the tower, coming down to the left of the tower, and smacking the north west corner of Bldg 3.

I again propose that the heavy debris was the green fuel handling machine, and I cannot dismiss that if it were hooked onto a single spent fuel rod assembly that was in the process of being uploaded for dry cask storage when the quake hit, that the FHM it took one with it on its ballistic trajectory (dark green parabola).

Refute it!

here is the video again

http://video.ft.com/v/825918290001/Fukushima-nuclear-plant-explosion

And here is a shot showing the direction of the wind after the blast, which also fits.

https://www.physicsforums.com/attachment.php?attachmentid=33860&d=1301658258

and here is what may be green fuel handling machine wreckage near the rod-like stuff at the north end of building 3

http://i306.photobucket.com/albums/nn270/tcups/64f1c409.jpg

and here is a wide angle shot of the entire complex showing a 4th tower at Units 5, 6 confirming the camera angle I suggest.

http://i306.photobucket.com/albums/nn270/tcups/WideAngleShot.png

Someone show me something that doesn't fit, please.
 
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  • #2,376
AntonL said:
considering the situation it does not make sense, the N2 will only replace steam, and future steam from RV will replace N2 ...

With the bubbler pool gone, a meltdown was less likely to produce a powerful steam explosion. To do so, the molten core would now have to reach the water table below the reactor. To reduce the likelihood of this, it was decided to freeze the Earth beneath the reactor, which would also stabilize the foundations. Using oil drilling equipment, the injection of liquid nitrogen began on 4 May. It was estimated that 25 metric tons of liquid nitrogen per day would be required to keep the soil frozen at −100 °C.[6]:59 This idea was soon scrapped and the bottom room where the cooling system would have been installed was filled with concrete. This is from the Chernobyl disaster . So they may be trying to do the same thing. http://en.wikipedia.org/wiki/Chernobyl_disaster
 
  • #2,377
timeasterday said:
I think that he is saying "stop it guys with all the speculation and photo examinations."

I have a headache from looking at all this stuff over the past week and am done squinting at photos until more info comes out. Until someone gets some eyes up close to this stuff (camera/robot eyes preferred) we can just go on speculating forever and not accomplish much.

Close your eyes, then. I intend to keep looking and trying to figure out what happened, though. Sorry.
 
  • #2,378
TCups said:
and here is what may be green fuel handling machine wreckage near the rod-like stuff at the north end of building 3

http://i306.photobucket.com/albums/nn270/tcups/64f1c409.jpg

and here is a wide angle shot of the entire complex showing a 4th tower at Units 5, 6 confirming the camera angle I suggest.

http://i306.photobucket.com/albums/nn270/tcups/WideAngleShot.png

Someone show me something that doesn't fit, please.

Does it look like something falling could have totally crushed the northeast corner of Bldg 3 with most of the damage directed downward? How did the damage to the building below happen? I think this is impact damage from above.

https://www.physicsforums.com/attachment.php?attachmentid=33768&stc=1&d=1301565672

Refute it, please.
 
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  • #2,379
TCups said:
Close your eyes, then. I intend to keep looking and trying to figure out what happened, though. Sorry.

No problem, please keep going. I didn't mean any offense. Glad to see you are thinking the fuel handling equipment went over to the north side as I suggested a while back.
 
  • #2,380
TCups said:
FROM WHERE WAS THE VIDEO OF THE EXPLOSION OF UNIT 3 TAKEN?

I cannot resolve the problem.
...
What angle, taken from the land, would put a tower aligned to the north end of Bldg 3?

What time of day in the northern hemisphere would put the south face of the buildings in shadow?

[

@TCups - maybe this will help and time of day 11:01AM the time the explosion occured

a 500mm telephoto lense has a field of view of 5degrees and explosion video is heavy telephoto as no colour definition,
 

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