Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[Homer Simpson]

For your theory to be justified, we need to resolve the question of how Oxygen becomes available within primary contaiment in sufficient volume to satisfy Hydrogen's UEL (considering the presence of steam). This issue has STILL hot been addressed.

There is no shortage of oxygen in the containment is there, it is air after all? Steam is factored when determining the hydrogen deflagration/detonation ranges of H2 in air. The presense of steam limits the ranges for explosion, but does not eliminate it.

 

[turbo]

So they messed up with Co-56 vs I-134, Cl-38, and Te-129/129m. And TEPCO is not sure about the Te-129

That certainly does raise concern. :uhh:

I've seen site and utility management replaced over much lesser problems.

I hope it's a matter of translation problems and/or exhaustion of the tech workers, and not a matter of incompetence. Finding high levels of very short-lived isotopes (indicative of on-going fission) should have set off some mental alarms in the engineering/technical staff, prompting a lot of double-checking.

With talk of entombment in some circles, this raises a concern in my mind. The process of setting/curing concrete is exothermic. Could entombment result in insufficient cooling of fuels, leading to unanticipated problems? Coming at this from a civil/mechanical mind-set with NO experience in nuclear leaves a lot of questions.

 

[skodises2]

As to panel trajectories from Unit 3...

Sketches I made some time ago but didn't post are attached. These were intended as a reply to a much earlier question about the origin of an almost intact panel leaning against the building just East of the turbine building.

The specific panel in question probably was a Southmost-East facing panel from either the top or second row of panels of Unit 3.

I just took a look at the satellite photos from post-tsunami, but pre-explosion. I'm not positive, but I think that that horizontal structure you are indicating was actually already there pre-explosion: I don't think that that is a panel from the reactor building. Check the attached image and see what you think. It looks to me like a drive-under weather shelter, perhaps, like a carport.

I'm looking to see if I can find a better image- but I think that that structure predates the blast, rather than somehow having survived it intact and come to rest there. What do you think?

On edit- added two more that also look tantalizingly as if that structure was already there. The last image, fuku3_6a.jpg, is a photo from prior to the earthquake and tsunami.

Having said that, I can see where my initial idea about trajectories posted above was flawed. Thanks, all, for the education...

Original images: http://www.digitalglobe.com/digitalglobe2/downloads/featured_images/japan_earthquaketsu_fukushima_daiichi_march12_2011_dg.jpg
https://lh6.googleusercontent.com/-...00/japan_fukushima_daiichi_after_03_14_11.jpg
https://lh6.googleusercontent.com/-...00/japan_fukushima_daiichi_after_03_14_11.jpg

 

[tyroman]

@Homer Simpson

The issue to be resolved is two-fold... What is "Hydrogen's UEL (considering the presence of steam)."? And what is the source of the Oxygen (as I remember, the primary containment is filled with N2)?

What we do not know is the relative (by volume) composition of the three gases (H2, O2 and H2O) in containment and whether that composition would support combustion.

Within your experience, how would we go about answering these issues?

.

 

[TCups]

I seriously doubt that the FHM can go ballistic like that. It's a slim and heavy structure that can not provide enough resistance to the expanding gases which would would just flow around it. It's like putting something inside a cannon which does not fit snugly, not enough momentum will be transferred to the object. I think with the first explosion, which is somewhat directed sideways, the FHM might be hurled against the north destroying that side, depending on the blast location, i assume would be close to SFP. In the top views of reactor 3, i also saw some green areas in the SFP, maybe those are pieces of the FHM as well. The first explosion looks kind of dirty compared to a hydrogen explosion, the fireball is very red/yellow, maybe the mixture was poor in oxygen. The implosion from that seems to trigger the secondary explosion. It might be a steam blast when a low gas density/vacuum formed in there. The explosion seems the pulverize a lot of the concrete stuff, hence the dirty dusty look. I think parts of the ceiling trusses are what are coming down afterward.

You are probably correct. After all, how could a blast like the large column rising in the center of this photo lift and toss aside something as massive as a fuel handling machine. BTW, what is the approximate size of that, uh, kind of green looking . . . "what are you-call-it" or "thingamabob" falling there to the right of the massive vertical column of the blast at unit 3?

http://i306.photobucket.com/albums/nn270/tcups/Falling-FHM.jpg

BTW, did you catch the earlier extensive photo analysis back there a few days ago where several of us spent hours lining up the towers, the sun, and the buildings to figure out where that long, green looking thing came down? That may have been wrong too, I suppose.

 

[Homer Simpson]

@tyroman,

Hi, my experience is nothing really, only that candu's have h2 igniters for this reason, mind you there is certainly no N2 cover gas for containment in candu's ...check the below link incase you haven't come across a chart such as this one... page 7/42

http://canteach.candu.org/library/20044507.pdf

 

[TCups]

Within your experience, how would we go about answering these issues?

Hell, maybe I am wrong about the blast coming out of the primary containment. Now that M. Bachmeier has pointed us toward the consideration of littoral explosions (you know, like the one that blew a few cubic miles of Earth out of the side of Mt. St. Helens a few years back?)

http://www.worldtravelattractions.com/wp-content/uploads/2010/10/Mount-St.-Helens-eruption-1980-300x200.jpg

Would you describe the eruption from the SFP at Unit 3 as "Vesuvial"? Most likely not.

http://toxipedia.org/download/thumbnails/442/Vesuvius1822scrope.jpg

http://i306.photobucket.com/albums/nn270/tcups/Falling-FHM.jpg

And after all, there was no dirt and rocks in Building 3, well -- only other stuff (concrete, asbestos, odds and ends and such). And hot fuel rods and hot magma don't have anything much in common, except, what? . . . Heat?

Sorry for being so sarcastic -- just tired this evening. But somehow my gut tells me that there was hydrogen below, hydrogen above, superheated water in the SFP and a blow-out of the fuel transfer gate touched the whole shebang off like a John Lee Hooker blues tune.

 

[M. Bachmeier]

You are probably correct. After all, how could a blast like the large column rising in the center of this photo lift and toss aside something as massive as a fuel handling machine. BTW, what is the approximate size of that, uh, kind of green looking . . . "what are you-call-it" or "thingamabob" falling there to the right of the massive vertical column of the blast at unit 3?

http://i306.photobucket.com/albums/nn270/tcups/Falling-FHM.jpg

BTW, did you catch the earlier extensive photo analysis back there a few days ago where several of us spent hours lining up the towers, the sun, and the buildings to figure out where that long, green looking thing came down? That may have been wrong too, I suppose.

Ya, let's calculate how much power could be in the blast?

Maybe "(60bar, 400C)= 3177.2 kJ/kg" or per liter. How many liters in primary containment at time of explosion? What was the pressure at the time of explosion? Either way it seems like enough power to put a small object in orbit...

See: http://me.queensu.ca/courses/MECH230/notes/documents/lect14-15.doc

 

[Homer Simpson]

post 3000. Holy cow.

Chinese, Japanese,Dirty Knees, Look at these... posts

 

[razzz]

This just in from TEPCO (May be a duplication)

At 5:38 am on April 6th, we observed the stoppage of the water spilling
from the crack on the concrete lateral of the pit. Details of the
situation will be announced after checking the blockage of the water
flows.

We will continue the countermeasure in order to prevent further outflow
of high level radioactive materials to the ocean.

From http://www.tepco.co.jp/en/press/corp-com/release/

Bob S

I'm glad they spotted the dye before it ended up in their coffee.

Laborer #1 & 2 will now be tasked to remove the 'injected' concrete (job security).

 

[yuriwho]

For those wondering where the oxygen can come from. Water can also be split into hydrogen and oxygen by temperature alone. It occurs above 2500 C and can be catalyzed by metal oxides which lower the temperature required. When the rods in the core are not covered with water, they can reach these temperatures and produce both hydrogen and oxygen even if the zirconium cladding is already burned.

see http://en.wikipedia.org/wiki/Water_splitting

edit added better link

 

[I_P]

"...
Among other problems, the document raises new questions about whether pouring water on nuclear fuel in the absence of functioning cooling systems can be sustained indefinitely. Experts have said the Japanese need to continue to keep the fuel cool for many months until the plant can be stabilized, but there is growing awareness that the risks of pumping water on the fuel present a whole new category of challenges that the nuclear industry is only beginning to comprehend.

The document also suggests that fragments or particles of nuclear fuel from spent fuel pools above the reactors were blown “up to one mile from the units,” and that pieces of highly radioactive material fell between two units and had to be “bulldozed over,” presumably to protect workers at the site. The ejection of nuclear material, which may have occurred during one of the earlier hydrogen explosions, may indicate more extensive damage to the extremely radioactive pools than previously disclosed. ..."

http://www.nytimes.com/2011/04/06/world/asia/06nuclear.html?_r=1&hp"

 

[razzz]

http://www.latimes.com/news/nationworld/world/la-fg-japan-nuclear-20110406,0,2697428.story"

Fishing of sand lances has been suspended. Local fishermen called on Tepco to halt the release of radioactive water into the sea and demanded that the company compensate them for their losses.

 

[AntonL]

This just in from TEPCO (May be a duplication)

At 5:38 am on April 6th, we observed the stoppage of the water spilling
from the crack on the concrete lateral of the pit. Details of the
situation will be announced after checking the blockage of the water
flows.

We will continue the countermeasure in order to prevent further outflow
of high level radioactive materials to the ocean.

From http://www.tepco.co.jp/en/press/corp-com/release/

Bob S

Now Tepco managed to dam the underground flow,
I wonder how long it will be for the next spring to appear.

 

[Jorge Stolfi]

And we never saw that wench again after the explosion.

There are some large orange-painted metal parts on the ground, between reactors #3 and #4, that could be pieces of the fuel handling machine. Additional pieces may have been covered by roof debris.

 

[yuriwho]

http://www.nytimes.com/2011/04/06/world/asia/06nuclear.html?_r=1&hp"

From the same article

The assessment provides graphic new detail on the conditions of the damaged cores in reactors 1, 2 and 3. Because slumping fuel and salt from seawater that had been used as a coolant is probably blocking circulation pathways, the water flow in No. 1 “is severely restricted and likely blocked.” Inside the core itself, “there is likely no water level,” the assessment says, adding that as a result, “it is difficult to determine how much cooling is getting to the fuel.” Similar problems exist in No. 2 and No. 3, although the blockage is probably less severe, the assessment says.

It's worth reading the whole article. Combined with the thermal production of hydrogen and oxygen from steam, this explains why they wanted to add N2 gas into the reactors.

 

[Jorge Stolfi]

Tepco do not understand their own measurements

I have asked this on twitter and got no answer, perhaps here: Does TEPCO have any nuclear engineers on its payroll? Or do they sub-(and subsub-)contract the entire operation of their nuclear plants?

 

[shogun338]

Is there any doubt at this point, that the pools are full of debris? And damage to the spent fuel rods is certain?

In the TEPCO helicopter flight over the Units the Helicopter spends the least amount of time over Unit 1 . My guess is radiation readings where so high he got out of there quick . But on the #1 video by TEPCO at 30 seconds the helicopter films what looks like left side of Unit 1 where the spent fuel pool should be and it is full of debris or covered with debris . At this 30 second mark you can see a bright red glow coming from a small point in this location . It looks like something is super heated on or under the debris at this point . If you go frame by frame in the video you can see it good . It stands out from everything else .

 

[tyroman]

@Homer Simpson

Excellent reference you posted!
http://canteach.candu.org/library/20044507.pdf

First question;
Most references I have seen give UEL at STP which would not apply within a hot - pressurized containment vessel... so, in Figure from R. Heck et al showing "Ignition tests performed with Siemens igniters." what were the temp/pressures for the tests? Can this be infered from the Steam Vol. % ?

Second question;
On the attached Heck diagram, how would you read the three Vol. % values for the point circled in red (just beyond the transition area)?

.

 

[ninefingers]

Now you have the mechanism for the initial fireball at the southeast corner, a ballistic FHM, damage to the equipment pool, blown out upper building, and blown out lower building including the access tunnel, all without a gross breech of the RPV (ie, melted fuel melting through the steel of the RPV).

Debunk that.


Last edited by TCups; T at 03:18 PM..

 

[ninefingers]

I know it's innappropriate but why do I keep hearing the William Tell Overture ? "BOOM!"

 

[Joe Neubarth]

That blog entry is correct. See also http://nucleardata.nuclear.lu.se/nucleardata/toi/nuclide.asp?iZA=520429 for data on Te-129m

The incredible thing is that Tepco do not understand their own measurements. See also http://www.nytimes.com/2011/04/06/world/asia/06tepco.html

Such a company should never have been allowed to operate a nuclear reactor.[/QUOTE

But that does not explain the blue glows above the reactor building.

 

[shogun338]

What is the long building in the background middle left ? It has no damage after tsunami . Now it looks like the end has been blown open .

 

[Emreth]

You are probably correct. After all, how could a blast like the large column rising in the center of this photo lift and toss aside something as massive as a fuel handling machine. BTW, what is the approximate size of that, uh, kind of green looking . . . "what are you-call-it" or "thingamabob" falling there to the right of the massive vertical column of the blast at unit 3?

http://i306.photobucket.com/albums/nn270/tcups/Falling-FHM.jpg

BTW, did you catch the earlier extensive photo analysis back there a few days ago where several of us spent hours lining up the towers, the sun, and the buildings to figure out where that long, green looking thing came down? That may have been wrong too, I suppose.

I've been following this thread since the beginning. I've seen all the analysis. The thing looks greenish but it might just be because it's in the shadow. I think it falls somewhere farther than the building anyway. The mushroom cloud is as wide as the building at this point and the object goes beyond.The remains of the FHM looks like scattered little pieces at the north end on the top view image.
There is probably enough force in the blast to launch an object that size but can that force be efficiently converted into momentum? I don't think so. The expanding gas when imparting the required acceleration to go that high would probably cause very high inertial forces that would rip it into small pieces, if the shock wave didn't already do it . It's like putting a dynamite next to it. Smaller pieces like the truss parts might survive it because they are lighter.
But maybe I'm wrong, FHM might be a very light structure welded out of bunch of metal sheets.

 

[razzz]

@Homer Simpson

Excellent reference you posted!
http://canteach.candu.org/library/20044507.pdf

Daams paper is interesting, seems a bit shortsighted in light of current events. Not design but possible outcomes. Saltwater and sand I didn't see addressed and (heated) brine is the worst when it comes to plumbing.

I only apply my extremely limited general knowledge towards it.

Suggests grating (air flow/venting) the floors instead of using solids (like concrete), now he tells us.

Suggest nitrogen gas will not cool as well as steam. That could be a problem if pressures are at the margins.

Only touched on dispersal concerning air temps and inversions. He did say, higher reaching plume the better. (I'm think'in stratosphere)

If they do inject nitrogen, I think they are trying to prevent more than just another hydrogen explosion...what could possibly go wrong?

 

[sp2]

I've been following this thread since the beginning. I've seen all the analysis. The thing looks greenish but it might just be because it's in the shadow. I think it falls somewhere farther than the building anyway. The mushroom cloud is as wide as the building at this point and the object goes beyond.The remains of the FHM looks like scattered little pieces at the north end on the top view image.
There is probably enough force in the blast to launch an object that size but can that force be efficiently converted into momentum? I don't think so. The expanding gas when imparting the required acceleration to go that high would probably cause very high inertial forces that would rip it into small pieces, if the shock wave didn't already do it . It's like putting a dynamite next to it. Smaller pieces like the truss parts might survive it because they are lighter.
But maybe I'm wrong, FHM might be a very light structure welded out of bunch of metal sheets.

Emreth--

So, you carefully watched the video, which clearly shows several gigantic pieces of debris launched a thousand feet in the sky and falling back to Earth, you carefully looked at the stills, which clearly show several huge pieces of debris falling to Earth from a thousand feet in the air... and then you concluded that there couldn't possibly *be* any large pieces of debris, because they would've had to be blown into small pieces by any explosion energetic enough to launch such large pieces of debris a thousand feet in the air.

Is that about it?

I'm speechless.

 

[Emreth]

Emreth--

So, you carefully watched the video, which clearly shows several gigantic pieces of debris launched a thousand feet in the sky and falling back to Earth, you carefully looked at the stills, which clearly show several huge pieces of debris falling to Earth from a thousand feet in the air... and then you concluded that there couldn't possibly *be* any large pieces of debris, because they would've had to be blown into small pieces by any explosion energetic enough to launch such large pieces of debris a thousand feet in the air.

Is that about it?

I'm speechless.

That's not what I mean. There are large pieces thrown up a long way up but they might be the large sections of the trusses above the SFP that are missing, which I would expect to be much lighter than FHM. It's about the mass really. I find it more plausible that the FHM got blasted sideways in the first explosion towards the north wall, destroying the wall and itself.
Again like I said I might be wrong, no need to get defensive or dismissive.

 

[rasherz]

http://www3.nhk.or.jp/daily/english/06_19.html

well, it seems that many of you are well ahead of the news, again. If the situation wasn't so serious over here, I would applaud.

 

[Jorge Stolfi]

Updated my plots of #Fukushima reactor temp, pressure, water level, CAMS to NISA/METI release 76 (apr/06 08:00) :
http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/Main.html

 

[AntonL]

here is a site worth following showing movies of calulated dispersion in the pacific of of contamination released by Fukushima for both water born and atmospheric releases.

the dilution does not seem to be so quick as what we expect

http://sirocco.omp.obs-mip.fr/outils/Symphonie/Produits/Japan/SymphoniePreviJapan.htm

 

[AntonL]

Updated my plots of #Fukushima reactor temp, pressure, water level, CAMS to NISA/METI release 76 (apr/06 08:00) :
http://www.ic.unicamp.br/~stolfi/EXPORT/projects/fukushima/plots/cur/Main.html

Jorge I really must thank you for your efforts in plotting this data

You may want to correct the flow rate measurements for the last couple of readings
I do not know why you omitted them, the flow rate published for Unit 1 as 6m³/h = 6000/60 = 100 l/h

 

[|Fred]

Sorry, this link added after (because i found it after) might help.http://en.wikipedia.org/wiki/Steam_explosion

Correct me If I'm not understanding this right: flash heating of water lead to fast vaporisation ie: cold watter on a hot pan. What you are suggesting is that the steam pressurized escaping the Primary containment entering the pool full of watter would flash heat the (large amount of) water in the pool ? Just like inserting a really hot metal blade into water?

Now isn't the suppression pool working exactly on the principle of cooling hot steam or gaz with water ?

as far as temperature are concerned we have a max pressure in the drywell of 0.490 MPa (75psi) does this value is consistent with a steam temperature hot enough to flash boil the pool ?

 

[NUCENG]

He he. But that is not reason not to try, is it? We are here mostly to learn, and for that asking stupid questions is essential...

I absolutely agree. I am fully qualified to ask stupid questions myself. I added that last part to explain that we need to be careful of interpreting these pictures. I have helped cleanup after floods, a house fire, tornados, and even a big earthquake in Okinawa, Japan. I can't tell you how many things you could pick up and ask "What the heck is this?" It is even more difficult when you are working only from photos, some blurred by steam, or taken through a helo window. The ability to determine scale is sometimes lost, and cameras have limited resolution. I will contribute from my experience and try to fill in BWR design information where I can.

I appreciate the imagination that has been shown and want everybody to keep looking. BTW, I just saw Charlie Sheen with his date near the Unit 4 snack bar. <};})

 

[Jorge Stolfi]

You may want to correct the flow rate measurements for the last couple of readings. I do not know why you omitted them, the flow rate published for Unit 1 as 6m³/h = 6000/60 = 100 l/h

However, from the TEPCO fax included in NISA release #76 (nominally dated apr/06 05:00), the last measurement of flow rate of unit #1 was taken on apr/03 17:30 and has not been updated since.

I do not know whether that means the rate has been stable since then. In doubt I have just been repeating the same data point at each release.

http://www.meti.go.jp/press/2011/04/20110406002/20110406002-2.pdf

 

[PietKuip]

But that does not explain the blue glows above the reactor building.

Blue glow is no evidence for criticality, only for ionization.

[PLAIN]http://m1.ikiwq.com/img/xl/zoWjYe4PwLmrJ3SmU37zUd.jpg

This is a photo of an x-ray beam at a synchrotron.