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Reactor meltdown possible in Japan.


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Here's an example -

http://www.tweetdeck.com/twitter/EMN/~l9ABg

#Tokyo Electric Power issues Article 15- Nuclear emergency situation at the #Fukushima Daini Nuclear Power Station NUMBER 3 Water feed not working

Take it fwiw because I haven't seen it confirmed anywhere else.

The article 15 is a standard process they have to go through for immediate notification -

http://www.nsc.go.jp/NSCenglish/documents/laws/8.pdf

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0421: If you've just joined us, here are a few pointers about the nuclear crisis now unfolding as a result of Friday's earthquake. The problem centres on one of two nuclear power plants in Fukushima prefecture, which stand 11.5km (7.1 miles) apart. The plant, Fukushima 1, has six reactors. On Saturday afternoon local time, a hydrogen explosion reportedly hit the building housing the No 1 reactor but the container of the reactor remained intact. Early today local time, it was reported that the emergency cooling system of Reactor 3 had failed. The reactor's fuel rods were reportedly exposed and a partial meltdown was believed to be under way.

0419: Possible fusion in two reactors - AFP, quoting government

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in reactor three these types of rods were/are exposed.......reactor 1, outside building exploded, has older type rods

http://blogs.princet...es_of_fuel.html

Mixed Oxide Fuel

Mixed oxide (MOX) fuel was developed as a means to reuse the plutonium that remained in spent nuclear reactor fuel. MOX also provides a means to burn weapons-grade plutonium to generate electricity. Currently, MOX is the new fuel used in about 2% of reactors around the world, and this proportion is expected to rise to 5% by 2010 (2).

In all fission reactors, there is both fission of isotopes such as U-235, and there is also neutron capture by isotopes such as uranium-238. The neutron capture is demonstrated in Figure 4. The successive neutron capture of plutonium-239 will form plutonium-240, plutonium-241, and plutonium-242. Plutonium-239 and plutonium 241 are fissile like U-235, and some of it will burn in the reactor, giving off about 1/3 of the energy in a reactor in which the fuel is changed every three years. If a reactor has a higher “burn-up” more plutonium will be used. Approximately one percent of the spent nuclear fuel is plutonium. Two thirds of this remaining plutonium is fissile.

Figure 4: Production of plutonium 239 from uranium 238

Image courtesy of Hyperphysics

This leftover plutonium can be used again as nuclear fuel. However, it can also be used in nuclear weapons. To read more about the plutonium problem, see The Debate over Reprocessing. Although the half-life of plutonium-239 is long, Pu-238 and Pu-241 have shorter life-times that will decrease the fissile value of the plutonium over time. Due to the short lifetime of some isotopes, the plutonium should be reprocessed immediately. If the plutonium is recycled, 12%* more energy is derived from the uranium, and if the uranium is recycled as well, this percentage increases to 22 percent* (These numbers are based on a light water reactor with burn-up of 45 GWd/tU) (2).

How can the leftover plutonium and uranium be recycled? Please see Reprocessing.

Plutonium oxide is mixed with depleted uranium leftover at the enrichment plant, forming a new mixed oxide fuel (UO2+PuO2). MOX fuel consists of about 7-9% plutonium mixed with depleted uranium and is equivalent to uranium oxide fuel enriched to about 4.5% U-235, assuming that the plutonium has about two thirds fissile isotopes.** If weapons-grade plutonium is used (>90% Pu-239), only about 5% Pu would be needed in the mix.

** Reactors with higher burn-up will have a smaller percentage of fissile plutonium (2).

MOX reactors are already being used commercially in Europe. France and Japan have plans to increase their usage of MOX fuel by 2010. Many reactors use up to one-third MOX fuel. Although MOX fuel can be used in several different types of reactors, the plant must be adapted for the MOX fuel. More control rods are required in the nuclear reactor.

MOX fuel has several advantages. The fissile concentration of the fuel can be increased by simply adding more plutonium, which is much cheaper than enriching uranium. As the price of uranium itself goes up, MOX fuel will become more attractive economically. Also, by using MOX fuel, one is burning left-over plutonium that could have been used for nuclear weaponry.

MOX fuel can be compared to plutonium-thorium fuel. For more information, see New Types of Fuel.

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Who would've guessed we would find out how to harness the power of fusion thanks to this disaster? :arrowhead:

Yes, finally! :) So I guess we'll need some sort of fusion disaster to finally figure out how to harness the power of antimatter :P

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Yes, finally! :) So I guess we'll need some sort of fusion disaster to finally figure out how to harness the power of antimatter :P

I will always remember some silly Steven Hawking video we watched in highschool where he said "If you find your lover and shes made of anti-matter you should hope you both never kiss." Or something on those lines anyways.

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Just a reminder that the people are still suffering from the earthquake and tsunami:

0436: Amid the anxiety over the power plant, the search for survivors goes on. According to Japanese media, in the small port town of Minamisanriku alone, some 10,000 people remain unaccounted for

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Not that I'd want to interrupt the frantic twisting of panic panties, but there's a huge difference between a meltdown and a meltdown with a containment structure failure. As a former resident of Harrisburg, PA, I'd like to note that TMI had a partial meltdown, but the containment structure held. The radioactive vapor release ended up being relatively harmless with virtually nil health impacts. (Though no doubt someone's friend is texting that N. Korean files reveal 3-headed Susquehanna calves were confiscated by the Bildeberg coverup wing of the CIA.) In contrast, Chernobyl didn't even have a containment structure.

Sometimes there is potentially bad, and worse, and catastrophe. Just because bad has happened, worse is possible, and catastrophe isn't unthinkable doesn't make the latter two even close to likely. I has to laugh last night at the headline repeated ad naseum of "Radiation levels 1000 times normal in control room!!!!" Of course the idiot media never bothered to put it into context with a reference point. In actuality the 'normal' level is so low that 1000 x is about the amount of radiation you'd get in 2 plane flights and less than that of a chest x-ray. (Now accumulated exposure over time adds up, but c'mon.)

Actually it is interesting to learn that a bit of increased radiation isn't necessarily bad for you, similar to how allergists can inject a small amount of allergen into a patient in order to innoculate them. Not quite the same, but some similarities.

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Just a reminder that the people are still suffering from the earthquake and tsunami:

0436: Amid the anxiety over the power plant, the search for survivors goes on. According to Japanese media, in the small port town of Minamisanriku alone, some 10,000 people remain unaccounted for

We have a thread for that. :whistle:

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This is for the Daiichi plant where the two reactors are suspected of being in some state of a meltdown. As usual with the update its from a few hours ago.

Official update -

Press Release (Mar 13,2011)

Impact to TEPCO's Facilities due to Miyagiken-Oki Earthquake (as of 8AM)

Below is major impact to TEPCO's facilities due to the Miyagiken-Oki

Earthquake that occurred yesterday at 2:46PM.

*new items are underlined

[Nuclear Power Station]

Fukushima Daiichi Nuclear Power Station:

Units 1 to 3: shutdown due to earthquake

Units 4 to 6: outage due to regular inspection

* The national government has instructed evacuation for those local

residents within 20km radius of the site periphery.

* The value of radioactive material (iodine, etc) is increasing according

to the monitoring car at the site (outside of the site). One of the

monitoring posts is also indicating higher than normal level.

* Since the amount of radiation at the boundary of the site exceeds the

limits, we decide at 4:17PM, Mar 12 and we have reported and/or noticed

the government agencies concerned to apply the clause 1 of the Article 15

of the Radiation Disaster Measure at 5PM, Mar 12.

* In addition, a vertical earthquake hit the site and big explosion has

happened near the Unit 1 and smoke breaks out around 3:36PM, Mar 12th.

* We started injection of sea water into the reactor core of Unit 1 at

8:20PM, Mar 12 and then boric acid subsequently.

* High Pressure Coolant Injection System of Unit 3 automatically stopped.

We endeavored to restart the Reactor Core Isolation Cooling System but

failed. Also, we could not confirm the water inflow of Emergency Core

Cooling System. As such, we decided at 5.10AM, Mar 12, and we reported

and/or noticed the government agencies concerned to apply the clause 1 of

the Article 15 of the Radiation Disaster Measure at 5:58AM, Mar 13.

In order to fully secure safety, we operated the vent valve to reduce the

pressure of the reactor containment vessels (partial release of air

containing radioactive materials) and completed the procedure at 8:41AM,

Mar 13,

* We continue endeavoring to secure the safety that all we can do and

monitoring the periphery.

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This is for the Daiichi plant where the two reactors are suspected of being in some state of a meltdown. As usual with the update its from a few hours ago.

Official update -

* High Pressure Coolant Injection System of Unit 3 automatically stopped.

We endeavored to restart the Reactor Core Isolation Cooling System but

failed. Also, we could not confirm the water inflow of Emergency Core

Cooling System. As such, we decided at 5.10AM, Mar 12, and we reported

and/or noticed the government agencies concerned to apply the clause 1 of

the Article 15 of the Radiation Disaster Measure at 5:58AM, Mar 13.

In order to fully secure safety, we operated the vent valve to reduce the

pressure of the reactor containment vessels (partial release of air

containing radioactive materials) and completed the procedure at 8:41AM,

Mar 13,

* We continue endeavoring to secure the safety that all we can do and

monitoring the periphery.

but why did they take so long to declare an emergency at number 3 until today if the cooling systems automattically stopped afrer the qauke

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but why did they take so long to declare an emergency at number 3 until today if the cooling systems automattically stopped afrer the qauke

From what I have read on Wiki the high pressure system they are talking about, is one of the emergency cooling systems, if that is what you are asking?

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From what I have read on Wiki the high pressure system they are talking about, is one of the emergency cooling systems, if that is what you are asking?

yes i am asking that,,but why would it automatically stop? if it was from the quake thats was almost 48 hours ago..why wait to declare an emergency until now while they did at the others

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