[meteorite-list] Not to worry. Nukes are good?

From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Sat, 12 Mar 2011 23:17:50 -0600
Message-ID: <DC7875BAA2B2414DB6E34A2832869A9B_at_ATARIENGINE2>

List,

Even though this is technically OT, it is a matter that
affects many List members personally. A lot of this List
discussion is wandering off-course.

Fukushima #1 was built in 1967 and began operations
in 1971. It is one of the oldest nuclear power reactors
in the world. It is also one of the largest (a somewhat
dated reference says the third largest). It is a Giant
Nuclear Teakettle, like most of the world's power reactors,
a bad design choice that originates in a hasty decision
made in 1948, the story of which I am not going to bore
you with here. Like all Water Boilers it combines nineteenth-
century steam technology with twentieth-century nuclear
technology. It is a design that has permeated a somewhat
uninnovative industry.

Right now, the best compilation of events at Fukushima
continuously updated is this newly created Wikipedia page:
http://en.wikipedia.org/wiki/Fukushima_I_Nuclear_Power_Plant

The five large reactors in the north of Japan were
sited there because it's relatively under-populated
and distant from the major cities. The UK puts its
reactors in Scotland, for example. Additionally,
Honshu has, in the past century, suffered fewer
and smaller quakes than the areas further south
where the biggest cities and greatest population is.
It was considered "safer."

Fukushima was never designed for a quake like this,
I suspect; almost no nuclear facility is. The Richter
scale being a log-10 scale, you can see this quake
was 100 times more powerful than the "likely" 100-yr.
maximum of a 7.0 quake.

Al Mitterling pulled Chernobyl into this. Chernobyl
was a graphite "pile" with pressurized water cooling
and NO containment vessel. In a graphite pile,
graphite is NOT a control material and the control
rods were not graphite rods. Fukushima is not a graphite
pile; Chernobyl is irrelevant to the Fukushima discussion.
And the suggestion that correct procedure for a water-
moderated reactor is let it boil off and expose the core
to meltdown is ludicrous.

Graphite is a "moderator." The moderator makes the
chain reaction happen. It is a substance that slows
the velocity of neutrons down until they are "thermalized,"
or moving with the kinetic energy of room temperature.
In the case of an neutron, that is the speed of an old man
crossing his living room (or me on a bad day).

ONLY slow neutrons can facilitate a chain reaction, slow,
bashful neutrons that can slip into an uranium nucleus
unnoticed, as it were, like the back door man. Graphite
slows them down.

Moderators can be almost anything with lots of hydrogen
atoms -- water is the most obvious choice, and that's what
"cools" the Fukushima reactor, yes, but the point is that
it is the moderator (the important point), combining the
two functions of cooling and slowing neutrons into one
substance.

"Control" material is stuff that sucks up neutrons, like
the Roach Motel for neutrons --- "neutrons go in; they
don't come out." Cadmium is excellent. A control material
that's almost too good is boron (takes in neutrons; emits
short-range alpha particles or helium nuclei with a
range of a few millimeters after which they find a couple
of electrons and settle down to be helium).

Boron is more than a control material; it was, in the early
days, called a "neutron poison." The contamination of
American graphite by traces of boron almost ruined the
attempts in 1940 to demonstration that a chain reaction
was possible.

So, if you actually look at the full data being released,
http://theenergycollective.com/dan-yurman/53397/update-japanese-nuclear-reactors-following-89m-quake
you will see that the current plan is to pump a
mixture of sea water and boric acid through the reactor
to "cool" it. Bah, they're not "cooling" it; they're killing
it. A few news sources have puzzled over the choice
of local sea water, which is corrosive.

Well, it's likely boiling in inside. The detection of cesium
means that fuel is exposed, which means its refractory
cover is gone, and it takes 5000 digress to melt that... I'd
guess it's boiling. Sea water will boil under pressure
but leave a salt crust behind. If the sea water is mixed with
boric acid, the salt crust will be full of boron. The boron
will absorb the neutrons and hinder, slow, maybe stop
the chain reaction. Natural boron is 80% isotope 10 which
is the "neutron-poisoner."

Then, there's the on-again, off-again story of the US flying
"coolant" to Japan. The two governments say, "no, well, yes,"
and "oh, yes, well, no" at random. Well, I think the best
material to pump into the reactor would be suitably diluted
drilling mud. Remember the Gulf oilwell blowout and the
talk of "drilling mud"? That stuff is dense gooey BORATES.
It would be the ultimate reactor killer.

Purely speculation on my part, but that might be the
mysterious "coolant" flown to Japan that they don't want
to talk about. And, I doubt there was any drilling mud
available in Japan, as they don't drill for oil; they buy it.

Unlike Chernobyl and Three Mile Island, this situation
is not the result of operator error, as they were. In both
those cases, the operators were unable to conceptualize
correctly what was going on inside the reactor despite being
deluged with information (or perhaps because of it).

For an appraisal of the complexity of the control process, see:
http://msexceptiontotherule.wordpress.com/2010/12/31/disaster-series-human-error-and-industrial-category-the-chernobyl-disaster/
and
http://en.wikipedia.org/wiki/Three_Mile_Island_accident

So the outcome depends on well the operators understand
their device and can deduce the true state of affairs within
it, difficult in the case of earthquake damage. The Boron Kill
might well achieve safety by sacrificing the reactor. Although
in truth, I don't if anyone knows if a boron-killed reactor
could be restored, and disasters are usually entombed in
this industry as not worth the effort.


Sterling K. Webb
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Tried posting this earlier today; it seems to have never
gone through. If this is a duplicate posting, apologies.
Received on Sun 13 Mar 2011 12:17:50 AM PST