Monday, August 13, 2012

Cracked Belgian nuclear reactor to remain closed, "Repairing the crack is practically impossible", says Belgium's nuclear safety agency chief


Doel Nuclear Power Station has 4 reactors, all pressurized-water reactors.

The company that made the vessels had gone out of business.

(I'm assuming the "steel tank containing a nuclear reactor" is the Reactor Pressure Vessel and not the Containment Vessel, but not quite sure from reading the article. If the readers in Europe know, please leave a comment in the comment section.)

(UPDATE: It is the Reactor Pressure Vessel. Thank you readers.)

From France 24 News citing AP (8/10/2012):

A crack discovered in a steel tank containing a nuclear reactor at a Belgian power plant will likely keep the station closed, the country’s nuclear safety agency said on Friday. Repairing the crack is "practically impossible," the agency said.

The head of Belgium's federal agency for nuclear safety AFCN said on Friday he was "sceptical" that an ageing reactor closed over fears of cracks could be restarted.

"I'm fairly sceptical for the moment," Willy de Roovere told RTBF public radio, even if "the possibility remains that I am wrong."

According to French-language daily Le Soir, a crack of between 15 and 20 millimetres (0.6 and 0.8 inches) was discovered during a test in June. There has been no denial of this report.

According to the agency, repairs are "practically impossible" and are "not an option" for fear of creating new tensions "which we must avoid at all costs."

Installing a replacement meanwhile has never been attempted anywhere because of the problem of high radiation levels.

The AFCN revealed on Wednesday that the Doel 3 reactor, located 25 kilometres (20 miles) north of Antwerp, would remain closed at least until August 31 after the discovery of possible cracks in the protective vessel surrounding the core during routine June testing.

The agency is also mulling the permanent closure "in the worst case" of a second reactor in the country's south near Liege.

The tests showed "faults in the steel base material" on which the reactor vessel is mounted, the AFCN said.

The Dutch firm, Rotterdam Drydocks, that made the vessels is out of business, which has amplified concerns about others it delivered in Europe and in the Americas.

Spain has indicated it has two reactors in the same bracket, Switzerland and Sweden one each.

The firm supplied one to the Netherlands, but had not manufactured it. The government in The Hague said it has still to decide whether to test its nuclear facilities.

The German government said reactors supplied by the defunct company were no longer in service.

Representatives of nuclear safety bodies from all the countries involved will meet in Brussels on August 16 to "exchange information," the AFCN said.

18 comments:

Anonymous said...

Off Topic: 82 years old nun Megan Rice penetrates US military nuclear facility. See details on the NY Times.
Beppe

Anonymous said...

http://gen4.fr/2012/08/faq-cuves-reacteur-fissurees.html

Pressure Vessel

Anonymous said...

Apologies, one more O/T: according to a NHK poll all of a sudden 39% of the respondents support the 15% choice.
As usual, the poll questions are not disclosed.
Beppe

arclight said...

hi admin
the ractor vessel is the core vessel with the rods and sorrounded by thick concrete

containment vessel, probably is refering either to the containment building or the reactor vessel

i hope thats right..
dyslexia and tired... :)

the reports talk of the reactor xessel and say we are safe because of the outer concrete shell..

a specialist mycel schnieder thought the problem nearly caused a meltdown..

http://nuclear-news.net/2012/08/12/expert-sparks-nuclear-fears-of-european-meltdown-after-belgium-shuts-reactor/#more-26808

link to greenpeace june 2012 european reactor report there as well that talks of doel .. not good!

peace to all here

arevamirpal::laprimavera said...

Thank you for info, anon and arclight. Does anyone know what may have caused the crack?

Anonymous said...

Here's another article in german:

http://www.derwesten.de/panorama/atomreaktor-in-belgien-nach-riss-im-mantel-abgeschaltet-id6965982.html

They too claim the crack is in the RPV.

The cause is most likely radiation-induced embrittlement of the RPV as it is almost 30 years in service, but of course material defects, stress induced to uneven welds and such can not be completely ruled out.

Anonymous said...

from the Belgium AFCN :
Belgium gov agency :

http://www.fanc.fgov.be/fr/page/fiche-d-informations-sur-le-reacteur-et-la-cuve-du-reacteur/1460.aspx#P_6752

Summarize = kelp type cracks from the manufacturing process. No "open" cracks, but inside the steel sheet, paralel to the tank.

Revealed with a new ultrasound checking process.

According to the admin at gen4, who seems to know a lot in the nuclear field, the tank has just 30 years of use, the scheduled time limit for safe use.
Impossible to repair. Very radioactive piece, so much that it can not be replaced.
His comment is that the defect processing must not let one underestimate the "fatigue" such pieces are subject to.


Que sait-on de ces indications de défauts ?

Il s'agit de défauts « laminaires », parallèles à la surface de la paroi et en tant que tels théoriquement pas dangereux, parce qu'ils ne sont normalement pas sujets à des tensions. Rappelons en outre que le réacteur est actuellement à l'arrêt du fait de la révision en cours sur Doel 3.

Retour en haut de la page
Comment se fait-il que ces indications de défauts n'ont pas été détectées plus tôt ?

Une nouvelle technique de mesure par ultrason a été utilisée pour la première fois en juin 2012 sur l'entièreté de la surface de la cuve de Doel 3. Cette inspection a été réalisée par une firme française spécialisée sur l'ordre d'Electrabel. C'est la première fois que l'on inspecte en Belgique le matériau de base de la cuve (en-dehors des zones de soudures). On a également inspecté l'entièreté de la paroi de la cuve, alors que les normes ASME XI prescrivent jusqu'ici uniquement le contrôle des zones sensibles.

Atomfritz said...

Interesting developments, please keep reporting!

Doel-3 and -4 are 3-loop Westinghouse PWRs.
Unit 3 delivered by Framatome, unit 4 delivered by Westinghouse.
Both have been uprated.
At least Doel-3 and Tihange-2 have been using REPU-MOX fuel since the 1990s.

(see link: https://docs.google.com/viewer?a=v&q=cache:cHdWlxW684EJ:www.icevirtuallibrary.com/deliver/fulltext/tf97v1.26193.0025.pdf%3FitemId%3D/content/chapter/tf97v1.26193.0025%26mimeType%3Dpdf+&hl=de&gl=de&pid=bl&srcid=ADGEESgaR_BmHRKQPsvjmKrExQOoHlSk_rQfLHoVL0eFovwOKW14hsH9h2fwQ7BoscAxRwIsAtdR004srGXfli5gyVHkFuACEozTHpnc-YuHE52paIty0kT0zgP_h88NkcZX98qfebl8&sig=AHIEtbRaXsugM1iRw_mWaXDcrDLFtz7_UA )

Doel and Tihange were used by the nuclear mafia as testbed showcase for REPU and MOX usage in uprated reactors.
And now these reactors appear to be damaged.

A very embarrassing situation to Electrabel, which is in heavy financial difficulties and has a strong wish to run their methusalem reactors at least 10 more years.

So I suppose the "experts" will "find" that the cracks are harmless because they were present since manufacturing time and have been found now only due to improved measurement technology, to have the plants restarted asap.

Anonymous said...

Wasn't there just recently a court order in Switzerland to scrap their (BWR) nuclear plant in Muehlberg due to cracks in the pressure vessel? While the Belgian Doel is a PWR, it seems to me that the issue of pressure vessel corrosion and cracking comes up rather frequently around the world.
Does anyone have any info on other plants that have had these issues?

Thanks. And thanks to laprimavera for keeping us all on our toes with collecting so much valuable info!
*mscharisma*

pat said...

no surprise the Rac cracked it's 30 years old these were designed for 25 year life.

I'd suggest that the damned thing is at end of life and now they need to toss it .

No easy fix, because it's in a radiation zone and not a service replacement item.

you can send welders in, but, the cost is fairly high and you would spend a long time in an outage, at least 2 years and you have to recertify, so maybe 3 years.

Forget it.

Write it off, like they should have 5 yars ago

Anonymous said...

"steel tank containing a nuclear reactor" = RPV, there is one and only one "vessel" on PWR technology and the containment is a full concrete one. No drywell, no PCV, no wetwell (torus)...

Regards,
Trifou

arevamirpal::laprimavera said...

@mscharisma, that was a crack in the core shroud inside the RPV: http://ex-skf.blogspot.com/2012/03/core-shroud-of-muhleberg-nuclear-power.html

Atomfritz said...

@mscharisma,
there are several courts involved.
the court order of June 1 only said that the authorities have to consider the demand of re-checking safety of Muehleberg instead of refusing checking safety and compliance with nuclear laws.
The court order of March 1 limited the unlimited operating permit to June 28, 2013.

So it is still not at all clear whether Muehleberg really will have to shut down.
Swiss activists now concentrate on NPP Beznau again, which is at 43 years currently the oldest nuclear plant of the world still in operation. In March 2012 there was even a primary circuit leak.

Anonymous said...

Thanks, laprimavera and Atomfritz, for the info. Much appreciated, as always.
*mscharisma*

Atomfritz said...

semi-OT:
By the way, the Swiss nuclear law determines that no nuclear plant is allowed to continue operation after the embrittlement transition temperature exceeds 93 degrees C.
(see the particular Swiss law paragraph here: http://www.admin.ch/ch/d/sr/732_114_5/a4.html )

This is a completely different safety mentality than in Japan.
In Switzerland it would be just impossible for a nuclear utility to continue reactor operation when the reactor transition temperature already rose to 98 degrees, as for example Kyushu's Genkai plant.

A "safety" attitude where an operator could find its reactor so rotten that it would burst open in case of accident emergency cooling, and say in spite of that finding "we want to continue to operate the reactor, and we'll do the next safety testing not before 10 years in future", and the nuclear safety oversight authority agreeing would be outright unimaginable in Switzerland.

Such observations suggest that the Japanese nuclear authorities even after the Fukushima incident still perform their "safety oversight" only pro forma.

TechDud said...

Headline:

"Belgian Reactor has Crack Problem,
to immediately undergo court-ordered detox & rehab!
Residents sentence temporarily suspended pending detox results." :/

Anonymous said...

@ Atomfritz:
I think the Genkai situation may well be the most underreported story of recent months. If the transition temperature rose 14 degrees in 16 years with no explanation for it whatsoever, it is, imho, criminally negligent that NISA goes along with Kyushu Electric to continue operating the reactor and not even test again until 2025.
(Asahi Shimbun article from July 28: http://ajw.asahi.com/article/0311disaster/fukushima/AJ201207280068)

It looks like financial interests may very well yet again have gotten the upper hand over safety considerations.
(Aug. 8 Japan Times article about debt securities issued by Kyushu Electric: http://www.japantimes.co.jp/text/nb20120808a9.html)
*mscharisma*

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