In another piece of brilliant journalistic excellence, Fox News this AM was announcing that the fuel rods in F-D #3 were "exposed" plus blah-blah-blah about nuclear radiation.
I am sure to the public that conjures up an image of the "explosion" having ripped the containment vessel assunder and there are the fuel rods exposed to the open air like a gutted deer carcass.
I don't think the public will be able to understand the sensationalism vs. what is actually going on. Another nail in the coffin.
The reactors are BWRs -- they have a steel containment building surrounded by a concrete/sheet metal reactor building. From the TV pictures, it appears that the reactor buildings for Units 1 and 3 have been damaged. However, from the various descriptions, it doesn't sound like the containment buildings are damaged.
Patricia Lougheed
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Wikipedia has a good (basic) description of a BWR.
Assuming the media got it partially correct : Where does the hydrogen that caused the explosions come from, a corrosion reaction ?
The hyrdrogen comes from radiolysis and from a zirconium oxidation reaction. The former dominates during normal operation, but the later dominates if the core overheats. You can find more information about this earlier in this thread.
A day ago, #2 was the only one of the 3 that we weren't worried about. Then report of core uncovered in unit 2. Now an explosion at a #2 in a different location than occurred in units 1 and 3....seems to be inside the containment:
Aside from the above mentioned explosion in @2 there are several reports the they are evacuating personnel from the plant due to problems with @2's exposed fuel rods. There was also mention of the loss of the containment pool on @2.
NHK stated that this last explosion was the second one in @2 reactor.
Just picked up on something I heard earlier. The fuel in @2 is a "duplex' fuel make from old nukes in Russia. There were no
percentages of each but the phrase a substantial amount of lutonium was present. This fue lsi only ussed in @2 reactor.
I realize that people read what they want into the various stories -- but I looked at the "evacuating personnel from the plant" as "things have stabilized enough that people can leave to tend to their families and homes."
There's a lot that is getting lost in translation. These plants don't have suppression or containment pools (they have torii).
Patricia Lougheed
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The seal around a reactor at a quake-damaged Japanese nuclear power plant does not appear to have been holed, the plant operator says, following an explosion at the plant.
Chief Cabinet Secretary Yukio Edano told reporters earlier on Tuesday that the suppression pool of the No.2 reactor at the Fukushima No.1 plant appeared to have been damaged.
The pool forms the base of the container vessel which seals the fuel rods.
Plant operator Tokyo Electric Power Co (TEPCO) "said it believes the container vessel has not sustained damage such as a hole, judging from the fact that the radiation level has not jumped," a spokesman for the country's nuclear safety said.
Here's the site for the Japan Nuclear and Industrial Safety Agency and their press releases. They give a lot of technical information about radiation levels and plant parameters.
A third reactor exploded late Monday at the Japanese nuclear plant crippled by Friday's earthquake, releasing a dangerous amount of radiation, officials said.
A fourth reactor was on fire and there were fears that the steel containment vessel protecting the plant's nuclear core had been breached - the worst-case scenario in such situations.
"There is a very high risk of further radioactive leaks," Prime Minster Naoto Kan said in an address to the nation."I ask you to stay calm."
More than 180,000 people living in a 12-mile radius of the Fukushima Daiichi plant 150 miles north of Tokyo had already been evacuated over the weekend.
Kan asked that people living between a 12- and 18-mile radius hunker down inside.
"Remain indoors, at home or in your offices," he said. "Avoid going outside."
Officials evacuated staff plant after reactor No. 2 exploded - the third blast there since Saturday.
A heroic team of 50 workers stayed behind to continue trying to cool the reactors with seawater and avert large-scale meltdown.
"They are putting themselves in a very dangerous situation," Kan said.
Tokyo Electric said a reading of 8,217 microsieverts per hour of radiation was taken at the plant's gates after the explosion - a fourfold increase from 40 minutes earlier
Hello everyone,
At the risk of removing any doubt about my intelligence for any that were wondering, I am going to ask a couple of things about this whole mess. But first, EP, I really wish I could go to that you-tube video but that is blocked on our network here at work. I really could use a chuckle. This whole thing is making me sick.
Ok the questions: Assuming the reactor vessel is not breached and containing all the neutrons, is there a possibility in the event of a complete fuel meltdown into one big "puddle" creating a fission explosion? I guess is there sufficient quantity of fuel there to attain critical mass? Seems to me I read a long time ago that if you were to put 110 lbs of U235 in a lead box and put a lid on it, it would go critical almost instantly and boom....Please dont hold me to that amount and that element, just the concept. It was a very long time ago.
Also, does anybody know what created that fire in unit 4? All I get from the news sites is speculation.
Thanks in advance
Scott
I really am a good egg, I'm just a little scrambled!
