Wednesday, December 7, 2011

#Fukushima I Nuke Plant: Suppression Chambers of Reactors 1 and 3 May Be Also Broken

Not just the Suppression Chamber of Reactor 2, as even TEPCO admits is broken from unknown causes.

From Nihon Television News 24 (12/7/2011):

福島第一原子力発電所の事故で撮影された水素爆発の瞬間の映像を分析したところ、1号機、3号機ともに原子炉格納容器の圧力抑制室が破損している可能性のあることがわかった。

Analysis of the hydrogen explosions at Fukushima I Nuclear Power Plant accident has revealed the possibility that the Suppression Chambers of Reactors 1 and 3 are damaged.

 これは、秋田県立大学・鶴田俊教授が7日、横浜市で開かれたシンポジウムで発表したもの。鶴田教授が分析した結果、1号機だけでなく3号機についても、爆発の際に核分裂生成物を含んだ飽和水蒸気とみられるものが建屋の外に出ていることがわかったという。このことから鶴田教授は、水素爆発によって原子炉格納容器の圧力抑制室が損傷している可能性が高いと分析している。

Professor Takashi Tsuruda of Akita Prefectural University reported in a symposium [Combustion Symposium] held in Yokohama City on December 7. According to the analysis by Professor Tsuruda, something that appears to be saturated steam that contains fission products is observed to escape from the reactor building after the explosions of Reactor 1 and Reactor 3. From this, Professor Tsuruda has concluded that the Suppression Chambers [for these reactors] are likely to have been damaged by the hydrogen explosions.

 鶴田教授「これだけの大量の水がある所といえば、格納容器の圧力抑制室の水くらいしか考えにくいだろう」

Professor Tsuruda says, "The water in the Suppression Chambers is the most likely source of this much water."

 鶴田教授は、爆発の詳しい状況を調べるために再現実験が必要だと述べている。

He says a simulation experiment would be necessary to further examine the explosions.

From his profile, Professor Tsuruda's specialty is reaction chemistry, and the study of combustion in particular.

7 comments:

Sebaschan said...

unknown cause... if there is a crack in a normal building after such an earthquake, nobody would say the cause for the crack is unknown... unless he has to hide that the earthquake was the cause, because he fears that other buildings will suffer the same fate...

Atomfritz said...

...what would mean that these other installations would better deactivated asap.

A few weeks ago the results of the French stress test were published.

The last catastrophical earthquake in the area of the two Fessenheim reactors was only 450 years ago and it was at estimated 6.2 magnitude. Back in the 1970s, the Fessenheim reactors were thus designed to withstand a 6.7 magnitude quake.

However, the official stress test published by the reputable IRSN and the ASN admitted that the tubing in this 35-year-old reactors would no longer withstand such an earthquake because of aging and wear, possibly leading to a loss of cooling accident as well as compromising the containment.

Furthermore, concern was expressed that the 1.5 meters of concrete insulation between the reactors and the ground soil might be insufficient reserve in case of meltdown.

The Fessenheim NPP is located at the Rhine, bordering to Germany. The main wind direction is towards Germany, the Rhine leaves French territory a few kilometers downwards.

Isn't this convenient?
In case of accident, France would get only negligible damage. Most of the pollution would hit Germany and the Netherlands (which depend to a major part on the Rhine for their drinking water supply).

Let's look towards, what will happen?
Will the Fessenheim reactors be decommissioned or will they get the desired lifetime extension?

(I sadly suppose the responsible people will not learn from Fukushima.)

Atomfritz said...

I have been wondering about why the official versions of what has been happening at Fuku I seem to become "officially recalled" piece by piece these days.

Now I read a very interesting presentation from a (pro-) nuclear professional working in safety consultation for nuclear plants.

The presentation, released on October 27, consists of 62 pages.
After a short introduction he shows in the first part of his presentation why the official Japanese hypothesis about how the explosive hydrogen formation happened cannot be correct.
In the same manner he disproves, by pointing out their weak points, the Areva and ENSI hypotheses,

In the second part of the presentation, from pg. 34 on, he describes his own hypothesis which I find very plausible and convincing.

He suggests that the hydrogen production in the spent fuel pool could have been caused by SFP cooling loss because of water siphoning through quake-damaged tubing/machinery.

As a result the fuel became uncovered, Hydrogen was produced by a zirconium-steam reaction. He explains also why the fuel looks seemingly undamaged in the videos/photos; the inner parts where the reaction takes part are shielded by steel clad.

Convincing also is the fact that after refilling of SFP #4 the radioactive releases were apparently reduced to a fraction.

Download the presentation from here:
Spent Fuel Pool Failure Analysis Revision 3 (27-10-2011)(PDF)
http://tec-sim.de/images/stories/spf-fa3.pdf


Maybe they begin to retract their official hypotheses now, partly because they knew better from beginning, partly because the stuff is even more uncontrollable than they ever dreamed of in their worst nightmares.


My personal nightmare for Japan:

In winter the tanks and the tubes freeze and burst, spilling their contents over the whole working area.
The plant has to be abandoned "temporarily" because radiation makes any human work kamikaze.
All fuel pools fall dry and burn out.
The groundwater sweeps out to the sea the core contents that concentrate in the basements.
Japanese will no longer talk about microsieverts, instead they'll live with millisieverts, as Fukushima became the nuclear Krakatoa of the 21. century.
Japan becomes a country of illness, pain and hopelessness.

I hope my nightmare remains a nightmare only.

Anonymous said...

Anything that stops the pumps for a few days would have the same consequences. My personal boogaboo is another earthquake but a typhoon or some sort of industrial accident could do just as well.

So far, Japan has been lucky. Every new day spent in this disaster-mitigation mode, with pumps and generators and holding tanks out in the open, uncovered SFPs, temporary piping, a single power line and so on is another pull on the revolver's trigger in a game of Russian roulette.

DD said...

Thanks for the link to the sfp analysis, atomfritz

Anonymous said...

PROVING THE PRINCIPLE

CHAPTER FOURTEEN

IMAGINING THE WORST

July 1954

"Worried that the excursion rod might
stick and so ruin the show for the visi -
tors, the crew decided to “give it every -
thing” they had when ejecting the
excursion rod by remote control from
the control trailer.
Almost instantly, the reactor blew up
with the force of three or four sticks of
dynamite, tossing debris and an inky
black column of smoke more than a
hundred feet above the desert brush.
.. Previous excursion clouds had been silvery
white, evidence of discharged steam
and water. This dark cloud, with almost
vertical sides, indicated a far different,
more powerful reaction. “Within the
column, and along its edges, and
falling away from the edges” Zinn saw
a “large quantity of debris,” including
a large sheet of plywood that sailed off
across the desert like a giant playing
card. "

There's an almost perfect description of your Reactor 3 explosion.

http://www.inl.gov/publications/d/proving-the-principle/chapter_14.pdf

Anonymous said...

There is no seismological evidence of an explosion in unit 2. The explosions in units 1, 3 and 4 were clearly detected by the plant's seismometers and analysis of arrival times of the p and s waves agree with the point of origin of the explosions as each of unit 1, 3 and 4. There is no need of an explosion to explain damage to the torus(es), as that may have been caused simply by heat. Of special interest is the photo of a door to the torus room IIRC of unit 3 that appears to be bowed outwards as if there had been some overpressure inside. By contrast, the torus room door IIRC of Unit 2 appeared virtually undamaged and was able to be opened.

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