andyrx

Drama in Japan--> schreckliches Beben und Tsunami

[andyrx]

<iframe class="video youtube-player" width="425" height="355" type="text/html" src="https://www.youtube.com/embed/dm2Hr-1l1MM" allowfullscreen="1" frameborder="0"></iframe>
Moin Motortalker

schreckliche Bilder aus Japan....ein Erdbeben dieser Stärke ist auch für das Erdbeben erprobte Japan ein Schicksalschlag😰

wenn da von bisher 5 Toten die Rede ist,braucht man nicht viel Phantasie um zu wissen das dies am Ende wieder tausende sein werden...die Zerstörungen sind massiv und das Elend wird groß sein.

Auto,Schiffe,Häuser und Bäume werden wie Spielzeug zerstört...jeder wird sich ausmalen können wieviele Menschen darin umgekommen sein werden🙁

Mein Mitgefühl gilt den Menschen in Japan und den betroffenen Regionen umzu....kaum eine Naturkatastrophe schlägt mit so viel Macht und folgenden Elend zu wie ein solches Beben.

mfg Andy

japan-001

[Schattenparker133861]

Gute Frage Andy.
Beton mit Salzwasser dürfte wohl nicht lange halten 🙄

[Multimeter47054]

Zum Thema "Ausfliegen", Lufthansa hat reagiert:

Zitat:

Die Lage in Japan hat zu einer vermehrten Nachfrage nach Oneway Tarifen geführt. LH hat reagiert und bietet einen exklusiven Oneway Tarif für €729 ex Japan an. Die Verfügbarkeit ist gewährleistet, bis die Buchungskapazitäten in Y/CL erschöpft sind. Höhere Preise, die im Netz kusieren basieren i.d.R. auf C/CL und F/CL Tarifen. So...llte die Nachfrage weiter steigen, würde LH im Rahmen der Möglichkeiten die Flugkapazitäten aufstocken. Weitere Infos unter: http://f.lh.com/mgby und http://f.lh.com/Bvd7 Alexander - LH Team

Und gleichzeitig nochmal, die hohen Preise kamen durch mangelnde Verfügbarkeit der günstigen Klassen zu Stande. Das tortzdem die Flugzeuge in der Economy nicht voll war, lag an den vielen "No-Show"-Passagieren, die zwar Tickets gekauft und teilweise sogar eingecheckt hatten, aber aufgrund der chaotischen Verhältnisse es nicht zum Flug geschafft haben.

Was ich mich nur frage, warum wird das in den Medien so sehr als Abzocke dargstellt? Die Journalisten müssten doch seblst oft genug unterwegs sein, um zu wissen, wie die Tarife zu Stande kommen. Oder macht man es nur, weil man sonst keine Meldung hat?

Übrigens, ich hatte gestern nochmal auf swoodoo.com nachgeschaut. Dort hätte ich für Samstag unter anderem bei British Airways einen Oneway-Flug ab NRT nach FRA für unter 700,- € bekommen. Man muss also nur ein wenig suchen. 😮

[Reachstacker]

Zitat:

andyrx:
...und wie kommt der Beton dahin wenn man es schon nicht schafft Wasser dort hinzubringen 😕

nach Ami Pumpen, Generatoren und Feuerwehr Auto's dann halt die 70 Meter

Ami Betonpumpe

von Putzmeister USA. Manchmal hat die globale Wirtschaft auch ihre guten Seiten. 😉 Aber soweit sind wir ja noch garnicht, erstmal muss weiter gekühlt werden.

Gruss, Pete

[Multimeter30590]

Öhm Du weisst aber schon dass Putzmeister eine süddeutsche Firma ist? 😁

http://www.putzmeister.de/.../index_DEU_HTML.htm

Und Putzmeister USA nur eine Tochterfirma bzw Filiale?

[Multimeter47054]

Ich schätze mal, da das Logo das gleiche ist, wird es sich um eine Niederlassung o.Ä. handeln. Immer wieder interessant zu sehen, was man in der Welt alles aus Ba-Wü findet.

[Multimeter30590]

Jupp findet man ja auf deren Seite die Putzmeisterusa ist halt eine der weltweiten Niederlassungen.

http://www.putzmeister.de/.../620_DEU_HTML.htm

Gibt ja nicht wenige Mittelständler aus D die weltweit aktiv sind.

[Reachstacker]

Und?

Fast alle Beton Spezialisten in den USA sind Deutsch oder Deutsch stämmig, was passt Dir daran nun wieder nicht? Hast Du das Wort "Global" in meinem Beitrag übersehen/nicht verstanden?

80% aller Kräne in US Betonwerken sind von Demag USA. Die Mehrheit der Betonaufbereitungs Technik in den USA ist Deutschen Ursprungs.

Wir diskriminieren hier nicht gegen Bayern.... wir benutzen was gut ist. 😉

Aber weil der Andy gefragt hat denke ich das wir von hier schneller liefern können, mit Glück sitzt so ein 70 Meter Beast gebraucht an der Westküste. 😎

Gruss, Pete

PS: es ist ein Werk, nicht ne Filiale

[Multimeter30590]

Das ist nicht "Deutschen Ursprungs" das ist ein deutsches Unternehmen zu 100% - da ist nur ameriksanisch dass halt die Filiale dort steht und sich putzmeisteramerica nennt in Japa heisst die Filiale putzmeisterjapan und in China putzmeisterchina, die sind halt nicht so einfallsreich 😁

[andyrx]

so ein Putzmeister Betonpumper schafft es auch noch das Zeug über den Teich zu sprühen😁😁😛

mfg Andy

[Reachstacker]

Eigentlich könnte so eine Mastpumpe besser Wasser auf den Reaktor kriegen als die kleinen Feuerwehrauto's, das Problem ist halt das es mindestens 2 Wochen braucht von der Westküste sowas ran zu schleppen.

Das ist ja ein grosses Problem mit der ganzen Tsunami Tragödie. Es gibt ja alle möglichen Dinge Weltweit die man gebrauchen kann. Nur braucht man sie jetzt, nicht in 4 Wochen...

Gruss, Pete

[Multimeter30590]

Jo die sind echt klasse - ich kenn das Unternehmen ein wenig, weil ein Bekannter von mir dort mal gearbeitet hat - halt nur natürlich so vom Drüberschlurfen.

Zur Not packt man das ganze auf einen Scheuerle drauf und karrt das irgendwo in eine Wüste

http://www.scheuerle.com/en/home/photo-competition.html

[schipplock]

na, dann ist ja auch geklaert, dass man das dicke Schiff, welches auf japanischem Festland gestrandet ist, nicht zerschneiden braucht 😉.

[Reachstacker]

Zitat:

Das ist nicht "Deutschen Ursprungs" das ist ein deutsches Unternehmen zu 100%

Willst Du mich manchmal mit Absicht nicht verstehen???

Les doch mal meinen ganzen Beitrag bevor Du anspringst... Putzmeister ist NICHT die gesamte US Beton Industrie!!! Ist mein Deutsch sooo schwer zu verstehen? Beton Industrie sind Tausende von Betonwerken, Firmen, Gerätehersteller, usw, und die Mehrheit davon haben Deutschen Ursprung, sind Deutsch stammig oder haben Deutsche Verbindungen! Spreche ich Chinesisch???

Putzmeister ist einer davon. Ja, sind ne gute Firma. Ich war in dem Werk in Wisconsin schon, weil ein Kran kaputt war.

Ganz Nebenbei: um 100% Deutsch zu sein hilft es wenn man Deutschen "Ursprunges" ist.....
Zumindest in der Altdeutschen Sprache. 😛

Ich denke oft missverstehen wir uns weil wir schreiben anstatt sprechen, da geht immer irgendwas schief... Du schreibst irgendwie nen anderen Dialekt. 😁

Gruss, Pete

[Multimeter30590]

Das mag sein 😁

Das Bild hatte ich gesucht: http://www.scheuerle.com/.../ALE_Weltrekord_Anlagentransport_01.jpg

:O :O

[deville73]

Auch ich habe jahrelang in der Nähe von Putzmeister in Süddeutschland gewohnt und weiss, was für Bellos die bauen.
Auch ist mir bekannt, dass die seinerzeit die bleigepanzerten Pumpen für den Sarkopharg in Tschernobyl gebaut haben.

Eine katastrophenerfahrene Firma.

[Reachstacker]

@ WHornung

Soll der Scheuerle das Ganze Fukushima einfach weg fahren? 😰

Da werden sich die Schwaben aber bei Dir bedanken. 😁

[Reachstacker]

@ deville73

Dann haben wir ja die richtige Firma gewählt. 😎

Muss der Andy halt den Tenno wieder anrufen, er wird sich langsam an den Hamburger Dialekt gewöhnen. 😁

Ist Putzmeister jetzt Bayrisch oder Schwäbisch?

Gruss, Pete

[deville73]

Schwäbisch

Putzmeister Holding GmbH
Max-Eyth-Str. 10
72631 Aichtal
Germany

48°37'52.72"N 9°13'51.53"E

[deville73]

Zitat:

18.03.2011 14:23 | WHornung WHornung
Das mag sein 😁
Das Bild hatte ich gesucht:http://www.scheuerle.com/uploads/pics/ALE_Weltrekord_Anlagentransport_01.jpg

Da ist ja die verschollen geglaubte crate-engine für meinen Tuning-Mondeo...

[Reachstacker]

Mal wieder was Ernstes....

Fukushima Update Friday (english text)

Schwimmbecken Nummer 3 ist halt kritisch. Nummer 2 macht Dampf (nehme an das ist gut)

Ami's kritisieren das Niemand auf Schwimmbecken Nummer 4 und 1 aufzupassen scheint. Die sehen da "Probleme" voraus...

Da scheinen immer noch nicht genug Pumpen, Wasserwerfer oder sonstwas vor Ort zu sein um da genug Wasser in alle die Schwimmbecken auf einmal zu kriegen.

Inzwischen haben die Japaner die Hubschrauberflüge wieder eingestellt....

Eine Nachricht das Strom angeschlossen wurde habe ich noch nicht gesehen...

Gruss, Pete

[Achsmanschette35866]

"Putzmeister" wäre dann eine regelrechte Onomatopoesis ('sprechender' Name).

[deville73]

Hier ist der Einsatzbericht von Putzmeister für Tschernobyl 1986 als pdf

[andyrx]

mal ne Meldung...

Zitat:

Ministerpräsident Kan hat Tränen im Gesicht, als er seinem Volk Mut zuspricht. Gemeinsam werden man Japan wieder aufbauen, verkündet er in einer Ansprache. Etwas mehr als 120 Männer stemmen sich unterdessen gegen den Super-GAU in Fukushima. Reaktoren werden mit Wasser beschossen, Stromleitungen wiederhergestellt. Trotzdem muss die japanische Atomsicherheitsbehörde die Schwere des AKW-Unfalls hochstufen. Unklar bleiben die Angaben über die Strahlungswerte in der Umgebung des AKW.

Quelle und ganzer Artikel-->

http://www.n-tv.de/.../...raft-gegen-den-Super-GAU-article2878961.html

wo ich mich frage,wo war der Mann und seine Tatkraft die ganze Zeit....soviel Zeit mit Untätigkeit verplempert,da muss man sich nicht wundern wenn jetzt kaum noch was zu machen ist.

Ein Krisenmanager ist das wirklich nicht🙄

mfg Andy

[Multimeter30590]

Dampf ist so halb gut eigentlich.... das kühlt zwar, aber damit Dampf entsteht braucht man ja ordentliche Temperaturen.... denn die werden ja kein erwärmtes Wasser abwerfen sondern +/- Lufttemperatur.....

Zumindest wenn man das auf die Aussenhülle abwirft und das dampft müsste die ja mind. 100 Grad haben? wenig ist das sicher nicht.

[schipplock]

wuerdet ihr eiskaltes Wasser auf euren Motor kippen, wenn er heiss gelaufen ist? Also ich nicht 🙂.

[Multimeter30590]

Naja aber wie willste denn das erwärmen was die Helikopter auf dem Meer aufnehmen?

[deville73]

Also wenn mein Motor brennt, würde ich schon zu löschen versuchen.
Notfalls mit dem was da ist und das mir geeignet erscheint.

[schipplock]

Richtig! deswegen denke ich auch nicht, dass das Betreiben der Pumpen noch irgendwas bringt, wenn man schon Wasser von oben raufkippt.

und kleiner Tipp, deville73: versicherungstechnisch kannst du dein Auto lieber abbrennen lassen *g+.

[Multimeter30590]

Hmmm aber nur bei Kaskoschutz! nicht dass der jetzt schon nach Streichhölzern sucht und im Internet Neuwagen konfiguriert 😁

[deville73]

Mein Mondeo ist noch priiiimaaa...
Und er Ami sowieso.
Der eine Fiesta ist grade durchrepariert, der andere auch und hat seit vorgestern wieder zwei Jahre HU.

Die DÜRFEN NICHT kaputtgehen...

Unsere Autos haben aber trotzdem alle eine Kaskoversicherung, schon wegen Diebstahl.

Aber das ist eher ein Thema fürs Versicherungsforum. 😉

[Antriebswelle33250]

Zitat:

wuerdet ihr eiskaltes Wasser auf euren Motor kippen, wenn er heiss gelaufen ist? Also ich nicht .

Nicht grad wasser, aber schnee auf den zu heissen mofa-zylinder hat immer gewirkt 😁 Ok, 2-3 klemmer waren dabei, aber wir wollen hier nicht erbsen zählen 😛

[deville73]

Der Tokio Ticker ist grad offline, der in Chiba zeigt momentan 0,10.

[Reachstacker]

Dampf meint nur das etwas wesentlich wärmer wie die Luft ist. Am Nordpol langt da schon +0.1C...
Dampf heisst aber auch das da Wasser ist das verdampfen kann und daher ein Kühlungseffect besteht, Allemal besser als Rot glühendes Metal ohne Wasser...

Ob der Dampf jetzt von der Reaktor Umhüllung kommt oder aus dem Becken sagt ja auch Niemand, also ist es müssig da Vermutungen anzustellen.

Summa Summarum = Positiv 😉

Ganz Nebenbei Leute: Jeder Dieselmotor läuft mit 84C Wassertemperatur, das er innen wärmer ist ist euch hoffentlich klar?

@ Andy

Tragischer Mann, etwa wie Carter. Guter Friedens Präsident aber nicht Jemand den man im Krisenfall als Kapitän haben möchte...

Gefährlichkeit jetzt auf Stufe 5 und: Ami's haben eigene Meinung. (english text) Scheins passt den US Spezialisten das runter spielen der Lage aus Tokyo nicht mehr so ganz...

Bis jetzt hat Tokyo mehr Zeit mit Face saving (Gesicht Sparen) verplembert als wie das ganze Gesicht nach US Meinung Wert ist. Ausserdem gefährdet dieser Quatsch unzählige andere ohne guten Grund und trägt absolut nichts zu einer Lösung bei.

Gruss, Pete

[andyrx]

ja der Vergleich mit Jimmy Carter passt ganz gut😉

netter Kerl und sehr friedliebend ....aber ohne ein Händchen und Tatkraft in entscheidenden Situationen😰

mfg Andy

[schipplock]

Zitat:

Ganz Nebenbei Leute: Jeder Dieselmotor läuft mit 84C Wassertemperatur, das er innen wärmer ist ist euch hoffentlich klar?

also diese Frage ist jetzt aber eine Beleidigung an das Forum 🙂.

eigentlich ist das jedem klar, der sich etwas mehr als Mutti mit Fiesta mit Autos auseinandersetzt 🙂. Und ausserdem haben wir doch diesen fetten Oel-Thread, der schon ueber mehrere Jahre hinweg mit Infos gefuettert wird.

[Reachstacker]

Also ich weiss nicht um Euch aber ich werde langsam Ungeduldig...

Wie sagte Obelix?: Die spinnen die Ami's Japaner. 😁

7 Tage

Weltweit beträgt die +75PS Pumpenbevölkerung mindestens 7 Millionen, und man kann keine nach Fukushima kriegen?

Die Weltweite Bevölkerung von 100-1000PS Generatoren ist mindestens auch so um 4 Millionen, aber in einer Woche haben wir es mit Ach und Krach geschafft einen in das Dorf zu schleppen???

Leute, wir reden hier doch nicht von Mond Technik und Werner von Braun! Hier geht es um Uralten Gammelkram wie ihn jeder Dorfschmied seit Jahrzehnten bei Hand bauen kann!

Dieselgenerator
Pumpe
Kabel
Rohr
Ventil
Spritze

Millionenfach sitzt das Zeugs weltweit in der Scheune. Aber wir kriegen es dort nicht hin?

Also langsam glaube ich doch was Andy sagt, Irgendjemand weiss nicht wo es lang geht...

[andyrx]

Zitat:

Dieselgenerator
Pumpe
Kabel
Rohr
Ventile
Spritze

da fehlen aber noch

Seitenschneider
Lüsterklemme
Isolierband
Rohrdistanzstücke
Stecker
Kupplung
Düse
Diesel
Wasserhahn

eventuell mal einen Einkaufszettel für den Baumarkt schreiben😛

mfg Andy

[Spannungsprüfer13299]

update: http://www.nisa.meti.go.jp/english/files/en20110318-3.pdf

Zwei Stände steigen. Becken der unit 4 unter 100°C.

______________

http://eq.wide.ad.jp/files/110318graphs_1600.pdf

Deutliche Entspannung bei den Radiation levels.

______________

Sehr gute Analyse:

Zitat:

Along with reliable sources such as the IAEA and WNN updates, there is an
incredible amount of misinformation and hyperbole flying around the internet
and media right now about the Fukushima nuclear reactor situation.

In the BNC post Discussion Thread, Japanese nuclear reactors and the
11 March 2011 earthquake (and in the many comments that attend the top
post), a lot of technical detail is provided, as well as regular updates.
But what about a layman’s summary? How do most people get a grasp on
what is happening, why, and what the consequences will be?

Below I reproduce a summary on the situation prepared by Dr Josef Oehmen,
a research scientist at MIT, in Boston. He is a PhD Scientist, whose father
has extensive experience in Germany’s nuclear industry.

This was first posted by Jason Morgan earlier this evening, and he has
kindly allowed me to reproduce it here. I think it is very important that
this information be widely understood.

Please also take the time to read this: An informed public is key to
acceptance of nuclear energy ? it was never more relevant than now.

I am writing this text (Mar 12) to give you some peace of mind
regarding some of the troubles in Japan, that is the safety of Japan’s
nuclear reactors. Up front, the situation is serious, but under
control. And this text is long! But you will know more about nuclear
power plants after reading it than all journalists on this planet put
together.

There was and will *not* be any significant release of radioactivity.
By “significant” I mean a level of radiation of more than what you
would receive on ? say ? a long distance flight, or drinking a glass of
beer that comes from certain areas with high levels of natural
background radiation.

I have been reading every news release on the incident since the
earthquake. There has not been one single (!) report that was accurate
and free of errors (and part of that problem is also a weakness in the
Japanese crisis communication). By “not free of errors” I do not refer
to tendentious anti-nuclear journalism ? that is quite normal these
days. By “not free of errors” I mean blatant errors regarding physics
and natural law, as well as gross misinterpretation of facts, due to an
obvious lack of fundamental and basic understanding of the way nuclear
reactors are build and operated. I have read a 3 page report on CNN
where every single paragraph contained an error.
We will have to cover some fundamentals, before we get into what is
going on.

Construction of the Fukushima nuclear power plants:

The plants at Fukushima are so called Boiling Water Reactors, or BWR
for short. Boiling Water Reactors are similar to a pressure cooker. The
nuclear fuel heats water, the water boils and creates steam, the steam
then drives turbines that create the electricity, and the steam is then
cooled and condensed back to water, and the water send back to be
heated by the nuclear fuel. The pressure cooker operates at about 250
°C.
The nuclear fuel is uranium oxide. Uranium oxide is a ceramic with a
very high melting point of about 3000 °C. The fuel is manufactured in
pellets (think little cylinders the size of Lego bricks). Those pieces
are then put into a long tube made of Zircaloy with a melting point of
2200 °C, and sealed tight. The assembly is called a fuel rod. These
fuel rods are then put together to form larger packages, and a number
of these packages are then put into the reactor. All these packages
together are referred to as “the core”.

The Zircaloy casing is the first containment. It separates the
radioactive fuel from the rest of the world.
The core is then placed in the “pressure vessels”. That is the
pressure cooker we talked about before. The pressure vessels is the
second containment. This is one sturdy piece of a pot, designed to
safely contain the core for temperatures several hundred °C. That
covers the scenarios where cooling can be restored at some point.

The entire “hardware” of the nuclear reactor - the pressure vessel
and all pipes, pumps, coolant (water) reserves, are then encased in the
third containment. The third containment is a hermetically (air tight)
sealed, very thick bubble of the strongest steel. The third containment
is designed, built and tested for one single purpose: To contain,
indefinitely, a complete core meltdown. For that purpose, a large and
thick concrete basin is cast under the pressure vessel (the second
containment), which is filled with graphite, all inside the third
containment. This is the so-called “core catcher”. If the core melts
and the pressure vessel bursts (and eventually melts), it will catch
the molten fuel and everything else. It is built in such a way that the
nuclear fuel will be spread out, so it can cool down.

This third containment is then surrounded by the reactor building.
The reactor building is an outer shell that is supposed to keep the
weather out, but nothing in. (this is the part that was damaged in the
explosion, but more to that later).


Fundamentals of nuclear reactions:

The uranium fuel generates heat by nuclear fission. Big uranium
atoms are split into smaller atoms. That generates heat plus neutrons
(one of the particles that forms an atom). When the neutron hits
another uranium atom, that splits, generating more neutrons and so on.
That is called the nuclear chain reaction.

Now, just packing a lot of fuel rods next to each other would
quickly lead to overheating and after about 45 minutes to a melting of
the fuel rods. It is worth mentioning at this point that the nuclear
fuel in a reactor can *never* cause a nuclear explosion the type of a
nuclear bomb. Building a nuclear bomb is actually quite difficult (ask
Iran). In Chernobyl, the explosion was caused by excessive pressure
buildup, hydrogen explosion and rupture of all containments, propelling
molten core material into the environment (a “dirty bomb”). Why that
did not and will not happen in Japan, further below.

In order to control the nuclear chain reaction, the reactor
operators use so-called “control rods”. The control rods absorb the
neutrons and kill the chain reaction instantaneously. A nuclear reactor
is built in such a way, that when operating normally, you take out all
the control rods. The coolant water then takes away the heat (and
converts it into steam and electricity) at the same rate as the core
produces it. And you have a lot of leeway around the standard operating
point of 250°C.

The challenge is that after inserting the rods and stopping the
chain reaction, the core still keeps producing heat. The uranium
“stopped” the chain reaction. But a number of intermediate radioactive
elements are created by the uranium during its fission process, most
notably Cesium and Iodine isotopes, i.e. radioactive versions of these
elements that will eventually split up into smaller atoms and not be
radioactive anymore. Those elements keep decaying and producing heat.
Because they are not regenerated any longer from the uranium (the
uranium stopped decaying after the control rods were put in), they get
less and less, and so the core cools down over a matter of days, until
those intermediate radioactive elements are used up.

This residual heat is causing the headaches right now.
So the first “type” of radioactive material is the uranium in the
fuel rods, plus the intermediate radioactive elements that the uranium
splits into, also inside the fuel rod (Cesium and Iodine).

There is a second type of radioactive material created, outside the
fuel rods. The big main difference up front: Those radioactive
materials have a very short half-life, that means that they decay very
fast and split into non-radioactive materials. By fast I mean seconds.
So if these radioactive materials are released into the environment,
yes, radioactivity was released, but no, it is not dangerous, at all.
Why? By the time you spelled “R-A-D-I-O-N-U-C-L-I-D-E”, they will be
harmless, because they will have split up into non radioactive
elements. Those radioactive elements are N-16, the radioactive isotope
(or version) of nitrogen (air). The others are noble gases such as
Xenon. But where do they come from? When the uranium splits, it
generates a neutron (see above). Most of these neutrons will hit other
uranium atoms and keep the nuclear chain reaction going. But some will
leave the fuel rod and hit the water molecules, or the air that is in
the water. Then, a non-radioactive element can “capture” the neutron.
It becomes radioactive. As described above, it will quickly (seconds)
get rid again of the neutron to return to its former beautiful self.
This second “type” of radiation is very important when we talk about
the radioactivity being released into the environment later on.


What happened at Fukushima

I will try to summarize the main facts. The earthquake that hit
Japan was 7 times more powerful than the worst earthquake the nuclear
power plant was built for (the Richter scale works logarithmically; the
difference between the 8.2 that the plants were built for and the 8.9
that happened is 7 times, not 0.7). So the first hooray for Japanese
engineering, everything held up.

When the earthquake hit with 8.9, the nuclear reactors all went into
automatic shutdown. Within seconds after the earthquake started, the
control rods had been inserted into the core and nuclear chain reaction
of the uranium stopped. Now, the cooling system has to carry away the
residual heat. The residual heat load is about 3% of the heat load
under normal operating conditions.

The earthquake destroyed the external power supply of the nuclear
reactor. That is one of the most serious accidents for a nuclear power
plant, and accordingly, a “plant black out” receives a lot of attention
when designing backup systems. The power is needed to keep the coolant
pumps working. Since the power plant had been shut down, it cannot
produce any electricity by itself any more.

Things were going well for an hour. One set of multiple sets of
emergency Diesel power generators kicked in and provided the
electricity that was needed. Then the Tsunami came, much bigger than
people had expected when building the power plant (see above, factor
7). The tsunami took out all multiple sets of backup Diesel generators.
When designing a nuclear power plant, engineers follow a philosophy
called “Defense of Depth”. That means that you first build everything
to withstand the worst catastrophe you can imagine, and then design the
plant in such a way that it can still handle one system failure (that
you thought could never happen) after the other. A tsunami taking out
all backup power in one swift strike is such a scenario. The last line
of defense is putting everything into the third containment (see
above), that will keep everything, whatever the mess, control rods in
our out, core molten or not, inside the reactor.

When the diesel generators were gone, the reactor operators switched
to emergency battery power. The batteries were designed as one of the
backups to the backups, to provide power for cooling the core for 8
hours. And they did.

Within the 8 hours, another power source had to be found and
connected to the power plant. The power grid was down due to the
earthquake. The diesel generators were destroyed by the tsunami. So
mobile diesel generators were trucked in.
This is where things started to go seriously wrong. The external
power generators could not be connected to the power plant (the plugs
did not fit). So after the batteries ran out, the residual heat could
not be carried away any more.

At this point the plant operators begin to follow emergency
procedures that are in place for a “loss of cooling event”. It is again
a step along the “Depth of Defense” lines. The power to the cooling
systems should never have failed completely, but it did, so they
“retreat” to the next line of defense. All of this, however shocking it
seems to us, is part of the day-to-day training you go through as an
operator, right through to managing a core meltdown.

It was at this stage that people started to talk about core
meltdown. Because at the end of the day, if cooling cannot be restored,
the core will eventually melt (after hours or days), and the last line
of defense, the core catcher and third containment, would come into
play.

But the goal at this stage was to manage the core while it was
heating up, and ensure that the first containment (the Zircaloy tubes
that contains the nuclear fuel), as well as the second containment (our
pressure cooker) remain intact and operational for as long as possible,
to give the engineers time to fix the cooling systems.
Because cooling the core is such a big deal, the reactor has a
number of cooling systems, each in multiple versions (the reactor water
cleanup system, the decay heat removal, the reactor core isolating
cooling, the standby liquid cooling system, and the emergency core
cooling system). Which one failed when or did not fail is not clear at
this point in time.

So imagine our pressure cooker on the stove, heat on low, but on.
The operators use whatever cooling system capacity they have to get rid
of as much heat as possible, but the pressure starts building up. The
priority now is to maintain integrity of the first containment (keep
temperature of the fuel rods below 2200°C), as well as the second
containment, the pressure cooker. In order to maintain integrity of
the pressure cooker (the second containment), the pressure has to be
released from time to time. Because the ability to do that in an
emergency is so important, the reactor has 11 pressure release valves.
The operators now started venting steam from time to time to control
the pressure. The temperature at this stage was about 550°C.

This is when the reports about “radiation leakage” starting coming
in. I believe I explained above why venting the steam is theoretically
the same as releasing radiation into the environment, but why it was
and is not dangerous. The radioactive nitrogen as well as the noble
gases do not pose a threat to human health.

At some stage during this venting, the explosion occurred. The explosion
took place outside of the third containment (our “last line of defense”),
and the reactor building.

Remember that the reactor building has no function in keeping the
radioactivity contained. It is not entirely clear yet what has
happened, but this is the likely scenario: The operators decided to
vent the steam from the pressure vessel not directly into the
environment, but into the space between the third containment and the
reactor building (to give the radioactivity in the steam more time to
subside). The problem is that at the high temperatures that the core
had reached at this stage, water molecules can “disassociate” into
oxygen and hydrogen ? an explosive mixture. And it did explode, outside
the third containment, damaging the reactor building around. It was
that sort of explosion, but inside the pressure vessel (because it was
badly designed and not managed properly by the operators) that lead to
the explosion of Chernobyl. This was never a risk at Fukushima. The
problem of hydrogen-oxygen formation is one of the biggies when you
design a power plant (if you are not Soviet, that is), so the reactor
is build and operated in a way it cannot happen inside the containment.

It happened outside, which was not intended but a possible scenario and
OK, because it did not pose a risk for the containment.

So the pressure was under control, as steam was vented. Now, if you
keep boiling your pot, the problem is that the water level will keep
falling and falling. The core is covered by several meters of water in
order to allow for some time to pass (hours, days) before it gets
exposed. Once the rods start to be exposed at the top, the exposed
parts will reach the critical temperature of 2200 °C after about 45
minutes. This is when the first containment, the Zircaloy tube, would
fail.
And this started to happen. The cooling could not be restored before
there was some (very limited, but still) damage to the casing of some
of the fuel. The nuclear material itself was still intact, but the
surrounding Zircaloy shell had started melting. What happened now is
that some of the byproducts of the uranium decay ? radioactive Cesium
and Iodine ? started to mix with the steam. The big problem, uranium,
was still under control, because the uranium oxide rods were good until
3000 °C. It is confirmed that a very small amount of Cesium and Iodine
was measured in the steam that was released into the atmosphere.

It seems this was the “go signal” for a major plan B. The small
amounts of Cesium that were measured told the operators that the first
containment on one of the rods somewhere was about to give. The Plan A
had been to restore one of the regular cooling systems to the core. Why
that failed is unclear. One plausible explanation is that the tsunami
also took away / polluted all the clean water needed for the regular
cooling systems.

The water used in the cooling system is very clean, demineralized
(like distilled) water. The reason to use pure water is the above
mentioned activation by the neutrons from the Uranium: Pure water does
not get activated much, so stays practically radioactive-free. Dirt or
salt in the water will absorb the neutrons quicker, becoming more
radioactive. This has no effect whatsoever on the core ? it does not
care what it is cooled by. But it makes life more difficult for the
operators and mechanics when they have to deal with activated (i.e.
slightly radioactive) water.

But Plan A had failed ? cooling systems down or additional clean
water unavailable ? so Plan B came into effect. This is what it looks
like happened:
In order to prevent a core meltdown, the operators started to use
sea water to cool the core. I am not quite sure if they flooded our
pressure cooker with it (the second containment), or if they flooded
the third containment, immersing the pressure cooker. But that is not
relevant for us.

The point is that the nuclear fuel has now been cooled down. Because
the chain reaction has been stopped a long time ago, there is only very
little residual heat being produced now. The large amount of cooling
water that has been used is sufficient to take up that heat. Because it
is a lot of water, the core does not produce sufficient heat any more
to produce any significant pressure. Also, boric acid has been added to
the seawater. Boric acid is “liquid control rod”. Whatever decay is
still going on, the Boron will capture the neutrons and further speed
up the cooling down of the core.

The plant came close to a core meltdown. Here is the worst-case
scenario that was avoided: If the seawater could not have been used for
treatment, the operators would have continued to vent the water steam
to avoid pressure buildup. The third containment would then have been
completely sealed to allow the core meltdown to happen without
releasing radioactive material. After the meltdown, there would have
been a waiting period for the intermediate radioactive materials to
decay inside the reactor, and all radioactive particles to settle on a
surface inside the containment. The cooling system would have been
restored eventually, and the molten core cooled to a manageable
temperature. The containment would have been cleaned up on the inside.
Then a messy job of removing the molten core from the containment would
have begun, packing the (now solid again) fuel bit by bit into
transportation containers to be shipped to processing plants. Depending
on the damage, the block of the plant would then either be repaired or
dismantled.

Now, where does that leave us?
The plant is safe now and will stay safe.Japan is looking at an INES
Level 4 Accident: Nuclear accident with
local consequences. That is bad for the company that owns the plant,
but not for anyone else.Some radiation was released when the pressure
vessel was vented.

All radioactive isotopes from the activated steam have gone (decayed).
A very small amount of Cesium was released, as well as Iodine. If you
were sitting on top of the plants’ chimney when they were venting, you
should probably give up smoking to return to your former life
expectancy. The Cesium and Iodine isotopes were carried out to the sea
and will never be seen again.There was some limited damage to the first
containment. That means that some amounts of radioactive Cesium and
Iodine will also be released into the cooling water, but no Uranium or
other nasty stuff (the Uranium oxide does not “dissolve” in the water).

There are facilities for treating the cooling water inside the third containment.
The radioactive Cesium and Iodine will be removed there and eventually
stored as radioactive waste in terminal storage.The seawater used as
cooling water will be activated to some degree. Because the control rods
are fully inserted, the Uranium chain reaction is not happening. That means
the “main” nuclear reaction is not happening, thus not contributing to the
activation.

The intermediate radioactive materials (Cesium and Iodine) are also almost
gone at this stage, because the Uranium decay was stopped a long time
ago. This further reduces the activation. The bottom line is that there
will be some low level of activation of the seawater, which will also
be removed by the treatment facilities.The seawater will then be
replaced over time with the “normal” cooling waterThe reactor core
will then be dismantled and transported to a processing facility, just
like during a regular fuel change.Fuel rods and the entire plant will
be checked for potential damage. This will take about 4-5 years. The
safety systems on all Japanese plants will be upgraded to withstand a
9.0 earthquake and tsunami (or worse)I believe the most significant
problem will be a prolonged power shortage. About half of Japan’s
nuclear reactors will probably have to be inspected, reducing the
nation’s power generating capacity by 15%.

This will probably be covered by running gas power plants that are
usually only used for peak loads to cover some of the base load as
well. That will increase your electricity bill, as well as lead to
potential power shortages during peak demand, in Japan.

If you want to stay informed, please forget the usual media outlets
and consult the following websites:

http://www.world-nuclear-news.org/

Gruß SRAM

[Multimeter47054]

@Andy und Pete
Man könnte auch sarkastisch sein und behaupten, die haben ihr Zeug bei Home Depot bestellt und warten auf die Lieferung.

Mir persönlich dauert das allmählich auch zu lange, in China wär das Dingen schon demontiert und alles wieder begrünt. 😁

Ok, genug Gift gespiehen.

[andyrx]

...ne das wäre dann der neue Platz ''des himmlischen Friedens''😎

mfg Andy