Japan Earthquake: Nuclear Plants at Fukushima Daiichi

[artax]

Still not looking good then, the news I've seen over the past two days has been reporting ludicrously optimistic statements like 'workers are reconnecting power to the stricken fukushima plant, in the hope of restoring cooling to the four reactors'
They need lots of help I feel from some disaster experienced engineers.
Reactor 1, blimey! they've been more concerned about 3 and 4, 1 is the least damage isn't it? maybe they'd better focus on two now!
Looks like we'll have black smoke from all 4 reactors by tomorrow.

 

[|Fred]

latest (exept t° went down to 330° in unit 1)
[PLAIN]http://i.min.us/ika7oo.jpg
[PLAIN]http://i.min.us/ijW5Ti.jpg

 

[jlduh]

@ FRED: ca you give the direct link to these two very informative pages?

Can somebody confirm the pressure readings: we talk about relative pressure to atmospheric pressure and not absolute pressure, of course (just want to make it clear to anybody)?

By the looks of their protection they can't be THAT concerned about radiation levels, which is a good sign.

I'm not sure you saw in the US the documentary (in french language) La bataille de Tchernobyl (The Battle of Tchernobyl), done in 2005, right?

In case you would like to see it (the images and archives from Soviet autorities are worth to see even if you don't understand everything), you can view it in 5 parts here:

http://www.chernobyl-day.org/article/la-bataille-de-tchernobyl

or here

http://www.dailymotion.com/video/x6xbsg_la-bataille-de-tchernobyl-15_news
http://www.dailymotion.com/video/x6xbys_la-bataille-de-tchernobyl-2-5_news
http://www.dailymotion.com/video/x6xc90_la-bataille-de-tchernobil-3-5_news
http://www.dailymotion.com/video/x6xci0_la-bataille-de-tchernobyl-4-5_news
http://www.dailymotion.com/video/x6xcqa_la-bataille-de-tchernobyl-55_news

You will see how to deal with high levels of radioactivity in case of high emergency... One million people have worked on the "liquidation" of the crippled soviet reactor. Most of them have been killed or got sicked. Most of them didn't even know what they were risking. The ones who intervened on the reactor itself ("cleaning" the roof for example: All of them died) have been called the "bio robots", because they were replacing the failed robots whose electronics couldn't bear the radiations levels...

I don't know how this accident has been covered and disclosed in the US from the citizen standpoint and knowledge. Here in Europe but especially in France, we had to wait until 2005 and this documentary to have a easy to understand tool to really be able to imagine what really happened there during the days, weeks and months after the accident.

Of course the subject here in Europe and France was very "touchy" (french are one of the "leaders" in nuclear energy) but on the other hand we were much closer from the catastroph and (some) citizens stayed very concerned and "vaccinated" by the combination of relative proximity and unacceptable silence and disinformation by the autorities (french and soviet).

Did US people know this documentary by the way? I don't know if an english version exists (it should be the case...)

 

[|Fred]

My sources for the Japanese figure are those http://www.jaif.or.jp/english/index.php
My source for the French way of safety assessing risk is the parliamentary hearing that was held on the 16.03.2011 the " Assemblée nationale"

According to NHK word http://www3.nhk.or.jp/daily/english/23_28.html

163,000 becquerels of radioactive cesium-137 per kilogram of soil has been detected in Iitate Village, about 40 kilometers northwest of the plant.

I'm failing at maths here..

 

[Borek]

One million people have worked on the "liquidation" of the crippled soviet reactor. Most of them have been killed or got sicked.

That's simply not true (to not say it is a lie). There was no "million" people working there, and total number of deaths that can be attributed to the accident is below 100. Estimates of the number of deaths that occurred later are also much lower (several thousands), unless one takes into account Yablokov book - but IMHO his estimates are in one (cracked) pot with the Moon hoax.

And it makes no sense to compare authorities in soviet Russia with Japan government - completely different culture and completely different approach; democracy vs highly censored police state. Russians worked as if nobody was looking at their hands, that's not the case in Japan. I am not telling Japanese are not trying to hide some information, quite possible they do, but the scale is incomparable and they have no tools for a fast and effective implementation of censorship.

 

[jlduh]

Thanks Fred. Are you french by the way?

The level in Iitate village soil is horrendously high taking into account the distance from the plant.

Based on what i see from last 10 days at the plant and now around the plant (combined to the info about tap water for example in this area which is the most contaminated it seems because of the winds http://www3.nhk.or.jp/daily/english/23_29.html , but even tap water of Tokyo is now of concern for children), i think the autorities are losing day after day control of the situation... Leaving people in the 30 (but also probably the 60 or 80 kms zone) is now really problematic. But how move so many people in a so dense country? The Tchernobyl area was, from this stand point, a little bit easier to handle i think.

 

[jlduh]

I found links for english version of The Battle of Tchernobyl (it seems the english version is from 2007 so 2 years after the french one).

It is in many parts on Youtube (10 parts) listed on this page from 1 to 10:

http://www.youtube.com/results?search_query=jimdangello+the+battle+of+tchernobyl&aq=f

 

[M. Bachmeier]

T-Cups and Antoni must be auditioning for Fox or one of the other news groups. Using limited knowledge, convoluted science, and conjucture. BTW, radiologically clearing a place and entering a cleared place are to diametrically opposites. Evidently you have not worked in contaminated areas or had to cleared them. Pictures do not always tell the whole story...that is how Fox news and others get attention. Have you got enough yet?

I wonder if you would mind qualifying your expertise sir. You apparently have very strong opinions about other contributors to this thread. At least one of the people you have slammed has credentials in two fields of study.

And, comparing anyone to FOX is an insult of an order of magnitude greater than 9.0.

Please tell us all why you know so much...

 

[jlduh]

@FRED: I already saw the regular tables and pdf on the JAIF site but I don't find from their main page the schematics your present above (which are a neat and clear presentation). Could you precise where to find them on their site? Thanks!

 

[|Fred]

My bad it was on NISA's and to be specific there http://www.nisa.meti.go.jp/english/files/en20110323-2-2.pdf
And as far as your question is concerned, the answer is: I'm

ps: the above file is now obsolete.. the new one is http://www.nisa.meti.go.jp/english/files/en20110323-3-2.pdf

 

[jlduh]

Ok thanks FRED, found it. The page to consult is this one:

http://www.nisa.meti.go.jp/english/index.html

and from there "seismic damage information". Then of interest for the nuclear situation is:

A) Conditions of Fukushima Dai‐ichi Nuclear Power Station Unit 1 (the reactors charts above)
B) Day xx Monitoring Data: precise radioactivity measurements on various plants (especially DAICHII plant of course)

Bonjour à toi sinon!

 

[AntonL]

Todays black smoke

 

[Borek]

I wonder if you would mind qualifying your expertise sir. You apparently have very strong opinions about other contributors to this thread. At least one of the people you have slammed has credentials in two fields of study.

https://www.physicsforums.com/showpost.php?p=3197462&postcount=2

Dean Chaney, CHP
37 Years in the Nuclear Industry (Navy, DOE, NRC, Reactort/Facility Decommissioning Consultant)

 

[M. Bachmeier]

Thank you Borek (re: post 917), but I don't think it is necessary to compare anyone with FOX news. I believe those contributors I refer to meant no harm and have just been caught up in a mystery or puzzle.
And, people often feel the need to help. Moreover, the lack of existing data (not made public) has only encouraged speculation.

 

[Borek]

Opinion on FOX News is on its way to became a banned topic, let's not touch it here (or at least - let's not continue, whatever has been said, has been said).

My understanding is that RD thinks there is too much speculation build on too thin knowledge. Can't say I disagree.

 

[rhody]

Since, the radiological protection staff at the reactors and emergency center are very competent, and you or I do not know the radiological situation being shown...then what you see is appropriate. Quit slamming stuff you probably know nothing about.

Dean Chaney, CHP
37 Years in the Nuclear Industry (Navy, DOE, NRC, Reactort/Facility Decommissioning Consultant)

Dean and/or Astronuc,

I would like to ask one or both of you a couple simple questions, if I understand correctly, with reactor #3 having the fuel that contains partial plutonium, I read the MOX wiki page http://en.wikipedia.org/wiki/MOX_fuel" . With that as background and an excerpt from the article: (please correct any inaccuracies that you see).

1. Does #3 have a special design to accommodate the MOX fuel ?
2. Does the MOX fuel heat faster, and cool slower, both in the reactor and in the spent fuel pools ?
3. If exposed to the air due to melting, what additional elements and in what quantities and toxicity from the MOX are released to the environment ?

Thanks in advance...

BTW, good job Borek, in keeping this thread on track, amazing that it has this many responses and for the most part has been trying to present accurate information, a credit to all who are doing their best to present accurate, timely information.

Rhody...

About 30 thermal reactors in Europe (Belgium, Switzerland, Germany and France) are using MOX[6] and a further 20 have been licensed to do so. Most reactors use it as about one third of their core, but some will accept up to 50% MOX assemblies. In France, EDF aims to have all its 900 MWe series of reactors running with at least one-third MOX. Japan aimed to have one third of its reactors using MOX by 2010, and has approved construction of a new reactor with a complete fuel loading of MOX. Of the total nuclear fuel used today, MOX provides 2%.[4]

Licensing and safety issues of using MOX fuel include:[6]

As plutonium isotopes absorb more neutrons than uranium fuels, reactor control systems may need modification.
MOX fuel tends to run hotter because of lower thermal conductivity, which may be an issue in some reactor designs.
Fission gas release in MOX fuel assemblies may limit the maximum burn-up time of MOX fuel.
About 30% of the plutonium originally loaded into MOX fuel is consumed by use in a thermal reactor. If one third of the core fuel load is MOX and two-thirds uranium fuel, there is zero net gain of plutonium in the spent fuel.[6]

All plutonium isotopes are either fissile or fertile, although plutonium-242 needs to absorb 3 neutrons before becoming fissile curium-245; in thermal reactors isotopic degradation limits the plutonium recycle potential. About 1% of spent nuclear fuel from current LWRs is plutonium, with approximate isotopic composition 52% 239
94Pu, 24% 240
94Pu, 15% 241
94Pu, 6% 242
94Pu and 2% 238
94Pu when the fuel is first removed from the reactor.[6]

 

[TCups]

All:

Those new to this forum, myself included, are here because we are hungry for good information regarding what has happened at Fukushima as a consequence of a natural disaster (quake, tsunami) and the chain of events that followed. This includes information about the actual damage, what caused it , and what it means to those who must now deal with it. There has been far more and better information exchanged here (yes, much of it speculative) than any network news outlets. Thank you all for contributing to my education.

But as for assigning any blame to TEPCO, or ascribing any particular motive to their actions or lack of actions as it relates to the consequences of a natural disaster, and what regulatory actions might be appropriate because of that: 1) I, for one, have no immediate interest, and 2) it becomes not only speculative, but risks becoming politically charged and very contentious. Neither is appropriate.

As a contrarian, one might ask, for example, if it were appropriate to plan for and build sea walls substantial enough to defend against a 15 meter tsunami around a particular power plant, then why not 15 meter sea walls around areas where the entire population of costal areas where of thousands of people died and properties were decimated, or, for that matter, around all of Japan? Let's not go there.

No offense was taken on my part, and if I have offended, or through ignorance, been overly speculative, then I stand corrected and humbly apologize for so doing. But surely the admonition from the PF Mentors to stay "on topic", which is, I believe, the nuclear power plants themselves, is entirely appropriate and constructive. Thank you for it. Keep the good information coming, please.

 

[joelupchurch]

Interesting article in the science section of NY Times today. Check it out before the paywall goes up.

http://www.nytimes.com/2011/03/22/science/22predict.html?pagewanted=1&ref=science"

Based on what the Geologists knew before March 11th, Fukushima was actually a pretty prudent place to put a Nuclear Reactor. Apparently the archeological records indicate there was a big tsunami in that area in 869 AD, but it was smaller than this one.

 

[AntonL]

Electricity is being connected, pumps are being tested and soon the external cooling should
be functional again, but how efficient will it be?

I redo a salt content estimation (https://www.physicsforums.com/showpost.php?p=3200617&postcount=702" was too high)
Assumption 1: Seawater injection rate 2 m3/hour as per https://www.physicsforums.com/showpost.php?p=3204597&postcount=906"
Assumption 2: Seawater salinity 34g/Litre or 34kg per m3 as per http://en.wikipedia.org/wiki/File:WOA05_sea-surf_SAL_AYool.png"

Today is the 11th day since sea water injection started and let's assume another two days
till pumps start working

--> 13 x 24hours x 2m3/hour x 34kg = 21216 kg salt

http://en.wikipedia.org/wiki/Solubility" degree C is 60g/100 liters or 600g per m3 of water
(or about 40g/100 l at room temperature thus we need to evaporate 90% of seawater for
crystallization to take place at room temp)

Therefore, to have a homogeneous solution of salty coolant we need:
21216/0.6 = 35360m3 of water

However the reactor is
5.4 metres in diameter and 19.2 metres high thus has an internal empty volume of 326 m3

The specific gravity of salt is 2.16 hence about 10 cubic metres of salt crystals will be in
the reactor vessel.

Anybody have an idea how this problem will be solved?

------------------------------------------------------------------------------

PS to Reno Deano - Electrical Engineer and Physicist here
fortunately never worked in the nuclear industry but in the power industry.

 

[Astronuc]

1. Does #3 have a special design to accommodate the MOX fuel ?
2. Does the MOX fuel heat faster, and cool slower, both in the reactor and in the spent fuel pools ?
3. If exposed to the air due to melting, what additional elements and in what quantities and toxicity from the MOX are released to the environment ?

1) Unit #3 does not have a special design. MOX fuel is designed to behave like a UO₂ assembly from a thermal standpoint. As I understand the available data, Unit 3 had 32 MOX assemblies - and probably not all fuel rods were MOX. They were part of a larger reload of on the order of 140-160 assemblies. One quarter of the core of 548 assemblies is 137, and they may reload slightly more or less depending on cycle length, capacity factor, and residual reactivity in the fuel. The MOX fuel can be placed in uncontrolled cells such that shutdown margin is not reduced.

Regarding

As plutonium isotopes absorb more neutrons than uranium fuels, reactor control systems may need modification.
MOX fuel tends to run hotter because of lower thermal conductivity, which may be an issue in some reactor designs.

PuO₂ and TU elements are dispersed in a UO₂ matrix. The portion of PuO₂ can be adjusted to an equivalence with a UO₂ assembly.

The thermal conductivity is slightly less than UO₂, but I don't consider that significant. One can design to control the power peaking. Fuel designers understand the difference between MOX and UO₂, so they can design to mitigate the effect of these differences.

The decay heat of MOX at a given burnup is slightly higher than UO₂, but that's not significant. After several months, I don't see the difference in decay heat being an issue.

2) MOX fuel may produce slightly more Xe, but less Kr, than UO₂ fuel at a given burnup. This fission gas release (Xe, Kr) from the fuel into the internal void volume may be slightly higher, but it's not significant IMO. See the attached figure for a comparison of fission product yields from thermal fissioning of U-235 and Pu-239.

3) The concern about MOX is due to the Pu istopes and transuranics (TU, or isotopes of Am, Cm) which are higher in MOX than UO₂ at the same burnup. The concern about fires involving nuclear fuel relates to the notion that some fuel particles may be released as aerosols and dispersed. A dispersed aerosol would increase the likelihood that folks could ingest or inhale the fuel particles. However, it is not clear to me that this is happening at Fukushima. Anytime there is a fuel failure, there is a concern about fuel particles escaping from the fuel rods and depositing within the reactor building.

Aside from U, Pu and other TU elements, the release of fission products from the fuel to the environment is a serious concern, regardless of the initial fuel matrix, e.g., MOX or UO₂.

Thanks in advance...

BTW, good job Borek, in keeping this thread on track, amazing that it has this many responses and for the most part has been trying to present accurate information, a credit to all who are doing their best to present accurate, timely information.

Rhody...

Thanks, Borek!

 

[intric8]

Just saw a news piece with DOH staff taking readings at the airport in counts per SECOND, yielding readings of 24cps off one traveler returning from japan and touting local background readings of "just" 6 cps. Question: why would any govt agency express readings in terms of cps instead of cpm, other than to downplay the exposures? this implies 1440cpm and 360cpm respectively, does it not? hope i am missing something here

 

[shadowncs]

Anybody have an idea how this problem will be solved?

10 cubic meters of salt would mean about 0.4 m of sediment layer if it were to settle (which it will not). As long as it is sloshy it can be moved by water pressure which is good.

If the main inlet to the PV is free of compact salt crystals (my guess is it will be) then they can pump in fresh water and steadily dissolve the salt by pumping in more water. No idea what they will do with the discharged water - they can't recirculate it and it is bound to be contaminated, heavily at first.

I remember reading about a filter system reactors have that filters any reactor water contaminants that are generated during regular use. Could this be used maybe?

While I love physics, I'm a software engineer so don't take my word for it.

 

[bondboy]

From Reuters: "Radiation at the crippled Fukushima No.2 nuclear reactor was recorded at the highest level since the start of the crisis, Japan's nuclear safety agency said on Wednesday. An agency spokesman said 500 millisieverts per hour of radiation was measured at the No.2 unit on Wednesday. Engineers have been trying to fix the plant's cooling system after restoring lighting on Tuesday."

from Kyodo:

Electric Power Co. said Wednesday it has observed a neutron beam, a kind of radioactive ray, 13 times on the premises of the Fukushima Daiichi nuclear plant after it was crippled by the massive March 11 quake-tsunami disaster.

TEPCO, the operator of the nuclear plant, said the neutron beam measured about 1.5 kilometers southwest of the plant's No. 1 and 2 reactors over three days from March 13 and is equivalent to 0.01 to 0.02 microsieverts per hour and that this is not a dangerous level.

Not trying to flame the fire here. The rad levels are low and I'm hoping TEPCO continues to make progress controling the site but the neutron beam got me thinking about reactor integrity. Neutron beams are product of fission correct? Would this finding confirm reactor damage even if it's just a pin hole?

 

[KateB]

I was actually just going to query on the neutron beam reported 1.5 km from the Fukushima nuclear plant. As a Biochem undergrad, my knowledge of physics is rudimentary at best, but wouldn't a neutron beam offsite signify release of plutonium/uranium, and to extrapolate further, does this mean that one of the spent fuel pools blew fissable material "sky-high"? What are the implications of this news? I have been following this thread for a while, and this has been a great pool of knowledge and learning for me.

 

[Reno Deano]

Just saw a news piece with DOH staff taking readings at the airport in counts per SECOND, yielding readings of 24cps off one traveler returning from japan and touting local background readings of "just" 6 cps. Question: why would any govt agency express readings in terms of cps instead of cpm, other than to downplay the exposures? this implies 1440cpm and 360cpm respectively, does it not? hope i am missing something here

They do that because they are not adquately trained or experienced HPs. CPS or CPM does not mean much unless you know the calibration of the instrument and radiation being detected. Hell, they could have been standing next to a pile of paper or within a high granite cement structure. I once had to do a followup survey of a building, (was currently a paper supply company) that was formerly use to make spacecraft parts using sightly enriched Thorium (60's). Between the stacks of paper the readings were about .3 to .8 mR per hour. All due to natural primordial Uranium and its daughter products.

 

[TCups]

Essentially what Kate is asking: What is the attenuation of neutron beams in air, and if a 0.01-0.02 microSievert source was detected, how far from the source of the neutron emission, if it were for example a fuel rod, might that be measured?

 

[artax]

No real news as such but some images of inside the control room, I'd like to know what guages they're looking at and the readings on them!
http://www.dailymail.co.uk/news/art...side-Japans-stricken-nuclear-power-plant.html

 

[83729780]

No idea what they will do with the discharged water - they can't recirculate it and it is bound to be contaminated, heavily at first.

it is returned to the ocean

http://hubpages.com/hub/Japan-May-Face-Even-Hotter-Water

...officials at Fukushima have confirmed that some of the water used to cool the reactors was returned to the sea after use.

 

[shadowncs]

it is returned to the ocean

If that is the case than the discarded sea water would carry away much of the concentrated NaCl from reactors which should make subsequent pumping less prone to failure.

 

[AntonL]

Wed Mar 23, 2011 5:46pm GMT
(Reuters) - The release of two types of radioactive particles in the first 3-4 days of Japan's nuclear crisis is estimated to have reached 20-50 percent of the amounts from Chernobyl in 10 days, an Austrian expert said Wednesday.

http://uk.reuters.com/article/2011/03/23/us-japan-quake-radiation-chernobyl-idUKTRE72M6OV20110323"

Remember Chernobyl also released huge amounts of nuclear material other than the isotopes mentioned above which have not been released at Fukushima