Posted on 03/12/2011 10:22:33 PM PST by SteveH
Edited on 03/12/2011 11:37:14 PM PST by Jim Robinson. [history]
The type of accident occurring now in Japan derives from a loss of offsite AC power and then a subsequent failure of emergency power on site. Engineers there are racing to restore AC power to prevent a core meltdown.
First came the earthquake, centered just off the east coast of Japan, near Honshu. The horror of the tsunami quickly followed. Now the world waits as emergency crews attempt to stop a core meltdown from occurring at the Fukushima Daichi nuclear reactor, already the site of an explosion of the reactor's housing structure.
(Excerpt) Read more at scientificamerican.com ...
“Remember that Japan tends to be all 50Hz and metric,”
Japan has both 50 and 60 Hz systems, divided North and South. Anything electric sold there must run on both!
I hit basic at Great Lakes October of 76 and stayed there till mid FEB 77 till I got through ATB {after basic training for those with no A school} and went straight to the carrier after that. I gave Navy four years and got my MM3 Crow then got out. I could not even have made it to MM1 likely and definitely not to Chief as I would have been medically booted out. I had to medically retire in my civilian job at 36 years old.
On the subject of rigging wiring from ship to shore here is a major problem part of which another poster reminded me of. The power on utility poles is roughly 6000-8000 volts and is ran on a fairly small ariel cable. That cable can serve hundreds of homes and many businesses. It has relatively low amps which means a thinner cable can be used. Look at your service drop coming into your home and compare the size of that cable to the size on the pole before the transformer. The Transformer steps down voltage to 220/240 volts and the amount of available amperage to your home increases thus requiring a larger conductor.
The line voltage coming from a commercial power plant can be as high as 500,000 volts on a thin conductor or cable. These are suspended up in the air for safety and for preventing leakage or loss of current to ground.
The cooling pumps guess a guesstimate {I wasn't a nuke nor have seen a nuke plant} are likely big motors requiring three phase 460 or 480 volt service and too it would depend on which type of Three Phase service they required for the wiring configuration. I Imagine either Sea-Bees, Army or Air Force might have a portable that can do it but I don't know that much about what their units can produce.
Please find a way to get some real sleep. You sound like you were wired from caffeine and unable to sleep when needed.
Do be careful and take care of yourself.
I know nothing about anything, but why didn’t they design the system such that the fuel rods are placed upwards and held in the core by electromagnetic force, such that a power failure would drop the rods down and out by gravity? Also, cooling water should be stored in a cistern above the reactor so that it too is gravity fed. Gravity never fails.
What the Japanese are when it comes to technology is a bunch of arrogant sob’s.
Yeah. I made it to BM3, then got out.
I wanted better pay (And to grow my hair long again).
As it happened, I achieved both.
Tsunami took out the backup systems, not the earthquake. Flooded the whole area where these plants are located. It was a one-two punch.
Tsunami took out the backup systems, not the earthquake. Flooded the whole area where these plants are located. It was a one-two punch.
The dignity and stoicism that the Japanese have exhibited throughout this entire tragedy is nothing but brilliant. They have my utmost respect and prayers. They give an example to the world of strength under adversity.
Here's an article.
http://climatesanity.wordpress.com/2011/03/13/why-i-am-not-worried-about-japans-nuclear-reactors-from-mits-dr-josef-oehmen/
In it the author states: "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), 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 typically built in such a way that the nuclear fuel will be spread out, so it can cool down."
LoL. They have made some good stuff though. Let see how they handle this latest disaster. You have to admit that you would rather have them helping you if this were us than just about anyone else other than the Germans who are even MORE arrogant.
Come on over here where there are people who know what is happening in Japan.
Right now, a sea water flood seems to be the best option.
It may not be possible to institute a boron slurry quench inside the reactor at the same time, but if the simple expedient of flooding with sea water works, go with it.
Would love to but currently stuck behind enemy lines here in the People's Republic of California. Besides my father (retired nuclear reactor engg mgr) likes it here which means I get to stay around.
That’s assuming the pumps weren’t damaged by the quake.
Hmmm. But if the fission restarts, will it be enough to melt the concrete?
...keep you fingers crossed.
Good point, the Germans can be a little over the top.
Ignoring him is one thing...actively “dissing” him is another. And that’s what this Country has been about for a number of years.
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