Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[TCups]

That's the spirit! they used i-robot http://www.irobot.com/

domo arigato, Mr. Roboto.

 

[NUCENG]

I think there's the problem. 33% is multiply by 0.33, not divide. Or divide by 3.


But I'm not sure as to what those 33% efficiency apply to in the calculations.


Edit: Screw that - you're right... ^^;

33% = the 760 MWe, 100% = total MWt

Hm, I also get your results...


But I think there are more factors contributing. First, it has not been 6 but 5 months or less since shutdown. And second, the pool is totally full AND there's probably debris inside, plus it's probably not filled up to the top. So if I double your 24 Bq/cm³ three times (three half times, less then one month) I get ~200 Bq/cm³. And because of the fill status /debris / water height there's probably not 900 billion cm³ water inside, but less.

Yep there was an error in my spreadsheet. Thanks for the second check. The source term is expressed in Ci per MW thermal. To produce 760 MW electric the reactor must produce abut 2280 MW thermal for the 33% efficiency. I am now coming up with about 11 Bq/cm³. with 6 months of decay. Backing that up to 5 months would give about 176 Bq/cm³. That is close to the value of 220 Bq/cm³ found in SFP4.

 

[clancy688]

domo arigato, Mr. Roboto.

Domo arigatoooo, Mr Robotooo

(sry, but you're responsible for having this song stuck in my head again...)NUCENG, did you read my notification? :)

 

[M. Bachmeier]

domo arigato, Mr. Roboto.

You forgot the link...

 

[Dmytry]

I disagree that "they didn't think of it ahead of time" means "it's likely impossible." Very simple mechanics and arithmetic says it is possible.

Strongly agreed. Even if there's some circulation, there has to be a lot of circulation to avoid geyser effect. I was sceptical but now I am convinced that your hypothesis is plausible. I still doubt it's the full picture, but it can happen, and if we're to discuss criticality in SPF we need to also think of geyser effect.

 

[TCups]

Speaking of fact checking and posting the correct references

The original video from the BBC without sound that I first viewed:


This is the explosion at Unit 1, StrangeBeatuy


The same video from Sky News without sound:


...and this is the explosion at Unit 3 -- hardly the same video, SB


Same video from Japanese TV again, without sound:


... and this is the explosion at Unit 3

The oztvwatcher version (who's that?) with sound:


...ah ha! Now you have it. The video and audio from the explosion at Bldg 3


Another video from Indian TV (?guessing here) with completely different sound:


Yes, indeed, the explosion at Bldg 1 does have a completely different sound than the explosion at Bldg 3! Amazing. I had probably missed that.

Which ones have been faked? They can't all be the original.

TCups, you may continue on your puzzle hunt, which has often been interesting -- but I'm just trying to keep you from wasting time on bad information. Yes, I'm suggesting fakery/fraud to gain viewers. It was obvious to me from the first time I heard it that was concocted since I've concocted such things myself for various purposes (e.g. foley work). Not only did I think this was concocted, but it was badly done - an obvious fake for the reasons I listed above. An actual, large explosion at that distance sounds nothing like that track. If a real soundtrack for the explosion became available why wouldn't the more reputable news organizations cover that? The bottom line, as an investigator, you need to prove your source is legitimate and that has not been done.

 

[StrangeBeauty]

Speaking of fact checking and posting the correct references

I sincerely apologize to the members for inadvertently including two videos of the #1 explosion.

Interestingly enough, one has sound and the other doesn't. Gee, I wonder how that could have possibly happened just like with the #3 videos...?

That said, my error does nothing to help you prove that the video of the #3 explosion with sound is legitimate. MiceAndMen asked good questions.

 

[Dmytry]

That was over 2 weeks ago - didn't they accept?

Last I heard they were considering it. Also last I heard they were offered this stuff in first few days. But by Areva and KHG rather than by Sarkozy and Merkel.
Does US have robotics equivalent to KHG?

 

[hbjon]

on topic of chemistry... in what form would the Cs exist? Wouldn't it take away O from UO2 becoming Cs2O ? Then in water, CsOH ?
Cs is far more reactive than U. I'd expect any Cs to immediately grab the oxygen from UO2

Since there is speculation here, let me say that I think Ba takes the O2 and quickly disintegrates and that is where the Cs gets a hold of it.

 

[M. Bachmeier]

I sincerely apologize to the members for inadvertently including two videos of the #1 explosion.

Interestingly enough, one has sound and the other doesn't. Gee, I wonder how that could have possibly happened just like with the #3 videos...?

That said, my error does nothing to help you prove that the video of the #3 explosion with sound is legitimate. MiceAndMen asked good questions.

I don't think anybodies trying to prove anything. In fact when I looked at the audio track my first objective was to try and determine if it was a fake (re: null hypothesis).

Having no strong reason to disbelieve, I tried to fit it together nicely. It did... So, I'm strongly inclined to believe the sound track I've presented to be legitimate.

 

[TCups]

I sincerely apologize to the members for inadvertently including two videos of the #1 explosion.

Interestingly enough, one has sound and the other doesn't. Gee, I wonder how that could have possibly happened just like with the #3 videos...?

That said, my error does nothing to help you prove that the video of the #3 explosion with sound is legitimate. MiceAndMen asked good questions.

StrangeBeauty:

No apologies needed and no worries, sir. That Steinbeckian skeptic does indeed ask some penetrating questions doesn't he?

It wasn't my intent to prove authenticity of the soundtrack or disprove it, and if I err, it is perhaps on the gullible side, as I usually presume something is authentic until it has been proven not to be. But if I erred on this one, it certainly wasn't because I hadn't considered the possibility or made some rudimentary effort to confirm it was authentic.

 

[ian_scotland]

RE Unit 4 roof slice theory...

I've been following this thread closely since 2nd week or so, but have mainly kept my mouth shut as I struggle to comprehend the "science bits". However, as an architect I grasp the "construction bits" reasonably well (thankfully!)

I have however been bowled over by the minds (an due thought processes) of several forum members here. Thank you for providing an insight into the Fukushima situation for me.

I have serious doubts that anything fell onto the roof of unit 4 or sliced through it. The north side of unit 4 is seriously out of shape. It is bulging out around the service deck level significantly. Together with dislocated columns and beams to the top-most NE corner, may I suggest that what we see in the photos is a structure that came within a hair's-breadth of looking like it's neighbour, unit 3. I shall attempt to find a photo and overlay a straight line tomorrow if I have time.)

As the main north wall ballooned outwards, its (possibly un-restrained) top has caved inwards, buckling the steel roof cross-bracing in the NW corner. Whether this significant blast removed the cross-bracing from the rest of that roof bay or it simply collapsed under the roof covering I haven't looked at in detail yet.

(Having now been able to look over the Oyster Creek constructional drawings -many thanks for the links - it is clear that large conduit voids, general services penetrations,varying wall masses etc would have a great effect on how the energy from any explosion would be channeled throughout any given level of the building.)

Commercial roof structures/coverings such as initially apparent in these reactor buildings tend to be corrugated uluminium (aluminum for USA folks) or steel sheets. These are what we can see scattered all around. They are fixed together with just enough bolts/nails to prevent uplift from the negative pressure above the building from gales. On top of these (as TCups has correctly researched) is typically a lightweight foam topped with approx 2-10mm of built-up waterproofing layers (usually rubber, bitumen or plastic based).

I've seen quite a few cases of building/roof failure, and would suggest that such a roof as discussed here would have neither the mass nor the rigidity to slice through/impact/bend the heavily reinforced concrete wall frame of unit 4.

Also to be discounted is any other flying debris (from unit 3). I'm pretty certain that one of the main posters on this forum has already posted an image of unit 3 post-BOOM, with unit 4 apparently intact. I shall try to dig it out and attach here too.

Sorry I've not gone into more depth just here - its not far from midnight and I've had a chaotic day of chasing my wee boy around, nappy (diaper) changing and general mayhem.

ps. The other good thing about following all the posts on this thread is that I've saved a fortune by not frequenting a certain on-line auction site over the past weeks, and am now in my wife's good books

 

[dh87]

In a previous post (#4111) I calculated the concentration of a 5% gap release of Iodine-131 into the pool from just the last core offloaded. Unfortunately I only accounted for a 30 day decay. Mr. Gunderson correctly indicated that the unit was shutdown 4 months before the accident. It has been a month since. So I repeated my calculation accounting for 180 days (6 months) of decay.

From an ORIGEN2 calculation of a BWR the core inventory of I-131 at 6months after shutdown is 5.03E-3 Ci per MW. Assuming 760 MW Electric and a 33% efficiency for Unit 4 leaves a total I-131 at the time of the accident of 5.23E5 Ci. In Taking 5% (gap release) and converting to Bq leaves 9.67E14 Bq.

I assumed a Fuel Pool of 40' by 20' by 40' deep. That converts to 1.81E9 cm^3.

Possible concentratiion of I-131 after 6 months in the fuel pool with only 5% of the source term released is up to 5.34E5 Bq/cm^3.

Personally I think Mr. Gunderson is absolutely correct when he ridicules TEPCO's explanation of Iodine deposition. But you do not need criticality to explain the concentration of I-131 they reported.

I try to keep reminding people that just because an isotope has a short half life does not mean it disappears in a few half lives. Half of a big number is still a big number. I-131 will likely be detectable beyond a year after shutdown.

In my first post, I'll try not to say anything too foolish, although I will be answering a post from 6 pages ago. I don't see that TEPCO's explanation is necessarily wrong. The volatilized iodine or iodide salts will stick to dust or other small particles. These may land on surfaces from which they can be blown elsewhere. When they land in water, the ions are permanently trapped. All the ions and the iodide dissolve in the water. Hence, Gunderson's calculation of how much I/I- had to be released to get 200 Bq/ml in SFP#4 isn't right. The SFP will concentrate the iodine from everywhere. Also, TEPCO added seawater from around the plant to cool the SFP. This seawater had radioactive iodine in it, and it's been concentrated by evaporation.

Some posters were wondering about the temperature of SFP#4. TEPCO reported 90 °C (http://www3.nhk.or.jp/daily/english/13_35.html ) when they measured the radioisotopes.

Two chemistry points. 1. The boiling point of I2 is 184 °C. It's hard to boil it out of water. 2. Iodine (I2) is pretty soluble in the water, and its solubility is increased by iodide in the water. In this case, there's probably enough iodide in the seawater.

 

[Borek]

1. The boiling point of I2 is 184 °C. It's hard to boil it out of water.

Boiling is not that important - iodine easily sublimes, so it doesn't have to go through liquid phase to become airborne.

 

[TCups]

HAPPY EYES WILL FOOL YOU EVERY TIME.

Well, once again, I fear my eyes are happy when they see what I expect them to see. But if I go brain dead and start from scratch, it is a lot easier to discover the obvious!

Take another look at the "undamaged" shot of Bldg 4 after the Bldg 3 explosion. . .

https://www.physicsforums.com/attachment.php?attachmentid=34633&d=1303253626

Now take a look at the attached hi-res photo "after" Bldg 4 has been damaged . . .

Does anyone else see what I now see??!

No hints. You have to find it yourself.

 

[Astronuc]

Boiling is not that important - iodine easily sublimes, so it doesn't have to go through liquid phase to become airborne.

and as far as I know, most iodine compounds are unstable, i.e., they tend to readily decompose in favor of other compounds + I₂.

 

[NUCENG]

Well, you could zip and upload them to a sharehoster... ^^

This would be very nice. :)

https://rapidshare.com/files/458267452/Upload_Refs.zip

let me know if I did this right.

 

[Dmytry]

and as far as I know, most iodine compounds are unstable, i.e., they tend to readily decompose in favor of other compounds + I₂.

hmm mmm. Iodine is a strong oxidizer and tends to readily react with a lot of compounds, oxidizing them or even replacing something.

 

[ian_scotland]

HAPPY EYES WILL FOOL YOU EVERY TIME.


No hints. You have to find it yourself.

Come on, just a small hint, the suspense is killing me here. Its way past my bed time and I can't wait another 6 hours!

 

[razzz]

HAPPY EYES WILL FOOL YOU EVERY TIME.

Well, once again, I fear my eyes are happy when they see what I expect them to see. But if I go brain dead and start from scratch, it is a lot easier to discover the obvious!

Take another look at the "undamaged" shot of Bldg 4 after the Bldg 3 explosion. . .

https://www.physicsforums.com/attachment.php?attachmentid=34633&d=1303253626

Now take a look at the attached hi-res photo "after" Bldg 4 has been damaged . . .

Does anyone else see what I now see??!

No hints. You have to find it yourself.

That was a bad link for me.

Guessing as always, but as been noted before Unit 4 appears to have exploded from the lower portions of the building causing the bottom to flare out and push the top inward and apparently no flight time for that roof section that remains fairly intact (per our newest architect poster) more like pushed and slid inward.
As you look at the picture, ground level or lower, a couple of venting areas bottom of pic and on the right side of building esp. underneath the piping that travels away passing between the next two buildings where there appears to be blast damage again coming from Unit 4 near or at ground level, one building taking the brunt of blast.

Also, sound tracks can be uploaded to YouTube if you just put in a dummy video (still shots, graphics, etc.)

 

[TCups]

Come on, just a small hint, the suspense is killing me here. Its way past my bed time and I can't wait another 6 hours!

Building 4 has already exploded. Two panels have blasted out of the east side and impacted on the west facade of the turbine building for Unit 4, and smoke is pouring out of the east side of Building 4. Your eyes aren't looking for it because you know this is "before" the explosion. But the impacts on the turbine building are real. They weren't there before the explosion.

https://www.physicsforums.com/attachment.php?attachmentid=34633&d=1303253626

 

[ian_scotland]

No hints. You have to find it yourself.

Smoke venting from top of vent tower between units 3 and 4 ?

 

[ascot317]

Building 4 has already exploded. Two panels have blasted out of the east side and impacted on the west facade of the turbine building for Unit 4, and smoke is pouring out of the east side of Building 4. Your eyes aren't looking for it because you know this is "before" the explosion. But the impacts on the turbine building are real. They weren't there before the explosion.

https://www.physicsforums.com/attachment.php?attachmentid=34633&d=1303253626

Might as well just be debris from #3 I've looked at different perspectives, sometimes it looks like dents, sometimes like pieces that are covering the roof's edge (debris of #3's roof maybe).

I can't come to a conclusion just by looking at this sat photo. The resolution is just too low (even with the original on flickr), and the perspective is the exact opposite of what you'd need.

I'm not even sure if I can see the wall piece on the two pipes on that photo.

It doesn't help to have clouds/smoke/vapor overhead. If you look closely, you can identify something that looks like vapor comming from the edge of #4 (similar to the hole in #2 sometimes), but that could be comming from the chimney too. However, in the west of the chimney, there's a "cloud", too. Hm.

 

[RealWing]

TEPCO Update Apr 18 - earthquake and current status

http://www.tepco.co.jp/en/nu/fukushima-np/f1/images/f12np-gaiyou_e.pdf

 

[ian_scotland]

Building 4 has already exploded. Two panels have blasted out of the east side and impacted on the west facade of the turbine building for Unit 4, and smoke is pouring out of the east side of Building 4. Your eyes aren't looking for it because you know this is "before" the explosion. But the impacts on the turbine building are real. They weren't there before the explosion.

https://www.physicsforums.com/attachment.php?attachmentid=34633&d=1303253626

Good analysis TCups.

But, I can't see the panels laying on the pipes in the "pre-explosion" picture. Damage to Turbine 4 building yes, but not panel on pipes. Could some of the same "stuff" that punctured the roofs of turbine buildings 3 & 4 have caught the west edge of turbine 4 wall too?

Also, I read the smoke as coming from top of the vent stack as opposed to east side of unit 4.

 

[TCups]

Might as well just be debris from #3 I've looked at different perspectives, sometimes it looks like dents, sometimes like pieces that are covering the roof's edge (debris of #3's roof maybe).

I can't come to a conclusion just by looking at this sat photo. The resolution is just too low (even with the original on flickr), and the perspective is the exact opposite of what you'd need.

I'm not even sure if I can see the wall piece on the two pipes on that photo.

It doesn't help to have clouds/smoke/vapor overhead. If you look closely, you can identify something that looks like vapor comming from the edge of #4 (similar to the hole in #2 sometimes), but that could be comming from the chimney too. However, in the west of the chimney, there's a "cloud", too. Hm.

You are correct about the debris on the pipe. It doesn't match. but the imacts on the turbine building look real. The sun is coming from the wrong direction to make them shadows. More panels did blow out later, though.

Addendum:

No, not to be. The stuff on the facade of the turbine building is laying over the edge, not damage from an outward blast. The smoke that looks to be coming from the east side of Bldg 4 is coming from the stack I guess. And the debris are from Bldg 3. So, BTTDB . . .

 

[dh87]

Boiling is not that important - iodine easily sublimes, so it doesn't have to go through liquid phase to become airborne.

This is a solution of iodine in water. I am not sure why the sublimation of iodine is relevant.

and as far as I know, most iodine compounds are unstable, i.e., they tend to readily decompose in favor of other compounds + I2."

I assume that you mean iodides. They're not especially stable in aqueous solutions, although I'm not sure about sweeping generalizations, and pH is likely a big effect. Even if the iodide is oxidized to iodine, I think that it will still stay in solution in water. The solubility of iodine in water isn't very large, but the solubility in seawater will be higher.

 

[I_P]

Building 4 has already exploded. Two panels have blasted out of the east side and impacted on the west facade of the turbine building for Unit 4, and smoke is pouring out of the east side of Building 4. Your eyes aren't looking for it because you know this is "before" the explosion. But the impacts on the turbine building are real. They weren't there before the explosion.

https://www.physicsforums.com/attachment.php?attachmentid=34633&d=1303253626

As I mentioned some time back the first reports of unit 4 problems said there were two 8x8m holes, fire evident, etc. After this there were pictures of the roof destroyed. In the first picture it does look like steam coming from the side of 4, but it could also be drift from the large amount coming from unit 3.

 

[ian_scotland]

Just for TCups...


New evidence of how unit 4 got to be the way it is.
There are 3 great forces in Japanese history:

1) Earthquake
2) Tsunami
3) ...





... yup, Godzilla!

 

[M. Bachmeier]

HAPPY EYES WILL FOOL YOU EVERY TIME.

Well, once again, I fear my eyes are happy when they see what I expect them to see. But if I go brain dead and start from scratch, it is a lot easier to discover the obvious!

Take another look at the "undamaged" shot of Bldg 4 after the Bldg 3 explosion. . .

https://www.physicsforums.com/attachment.php?attachmentid=34633&d=1303253626

Now take a look at the attached hi-res photo "after" Bldg 4 has been damaged . . .

Does anyone else see what I now see??!

No hints. You have to find it yourself.

O.K. I'll bite. Does it look like a small hole in the roof of #4 and is there steam escaping from the east side of the building?

 

[OnlyOneTruth]

http://www.tepco.co.jp/nu/f1-np/intro/outline/outline-j.html" from TEPCO after you pipe it through a translator.

Starting from the link to TEPCO's historical fukushima information I posted earlier, I've been digging through TEPCO's website and found some interesting bits I thought I should share:

• Construction of No4 started 9 months after construction of No5 (1972-9 vs. 1971-12)
• No4 is the only FukushimaDaichi reactor built by Hitachi, the other reactors were built by GE/Toshiba

CHronology at http://www.tepco.co.jp/nu/f1-np/intro/outline/outline-j.html has historical photograph of (No1?) construction:
[URL]http://www.tepco.co.jp/nu/f1-np/intro/outline/images/his_11.jpg[/URL]

Chronology also contains links to documentation of security audits, the second PDF on http://www.tepco.co.jp/nu/f1-np/press_f1/2008/htmldata/bi8a07-j.html is an appendix to a 2008 audit of No4 with loads of data and some visual documentation. I'll add two thumbs as a teaser:

I'm a quite tired and haven't checked everything, Not knowing Japanese, fiddling with Google translate, doesn't make things easier, so please be gentle if something I wrote is not accurate. I thought I'd share this before going to sleep. Cheers

 

[razzz]

Unit 4 is preloaded with gases causing the roof to balloon up but then an initial blast is from the lower floors out the lower side/relief panels. Looks a bit sooty at ground level venting areas. Why was Unit 4 steaming away where it was before the unseen blast? Ground water or leakage from the neighbors seeping in? But what is the heat source (and a lot of it) to cause steam at lower levels? Can one dry cask contain enough fuel to cause a steam/hydrogen explosion?

 

[MiceAndMen]

Thanks, Fred. I replied above before seeing your post. It's a start. I, too, remember hearing initially that a helicopter recorded the video, but I don't remember where I heard that.

Replying to myself and |Fred here... Page 31 of this NISA pdf file
http://www.nisa.meti.go.jp/english/files/en20110406-1-1.pdf
has side-by-side pictures of the Unit 1 and Unit 3 explosions. From that I think it's safe to say those pictures were taken from a fixed camera position. Was the video of the Unit 3 explosion from the same vantage point? If so, can we rule out that the video was recorded from a helicopter?

 

[etudiant]

The expertise deployed on this forum to understand the processes which reduced four multi billion dollar reactors to steaming scrap is laudable.
For an outside observer, it would be wonderful if this expertise were also employed looking forward, to help evaluate and understand the challenges and risks posed by the clean up plan.
For instance, Areva is scheduled to have a water processing plant built by the end of June that will process 1200 tons of water/day. There are nearly 70,000 tons currently in the facility, increasing at 500tons/day, so there will be 100,000 tons by the time the plant is operational.
The plant will start to whittle down the flood at about 700 tons/day net once it starts, so it will take 150 days to drain the facility, if all goes well.
That says the cleanup will not begin until very late this year at the earliest.
Is this a plausible schedule? How does it tie into the TEPCO indication that the immediate crisis should be stabilized within 9 months? What are the risks that should be of most concern?

 

[Dmytry]

The expertise deployed on this forum to understand the processes which reduced four multi billion dollar reactors to steaming scrap is laudable.
For an outside observer, it would be wonderful if this expertise were also employed looking forward, to help evaluate and understand the challenges and risks posed by the clean up plan.
For instance, Areva is scheduled to have a water processing plant built by the end of June that will process 1200 tons of water/day. There are nearly 70,000 tons currently in the facility, increasing at 500tons/day, so there will be 100,000 tons by the time the plant is operational.
The plant will start to whittle down the flood at about 700 tons/day net once it starts, so it will take 150 days to drain the facility, if all goes well.
That says the cleanup will not begin until very late this year at the earliest.
Is this a plausible schedule? How does it tie into the TEPCO indication that the immediate crisis should be stabilized within 9 months? What are the risks that should be of most concern?

it is impossible to predict anything there imo. I would of never thought they'd be using 2 robots, one with radiation monitor strapped to it, other to look at the monitor, 38 days in, versus some KHG robot.