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Third Blast At Japan's Fukushima Nuclear Plant
iamrmani was one of several people reporting updates on the Fukushima Nuclear plant that has been struggling following last Friday's disaster. A third explosion (Japanese) has been reported, along with
other earlier information. MSNBC has a story about similiar reactors in the US. We also ran into a story which predicts that there won't be significant radiation. But already Japan is facing rolling blackouts, electricity rationing, evacuating the area around the plant, and thousands dead already.
Poorly constructed sentence that last one, insinuating the deaths are related to the nuclear plant.
Is not the third explosion.
means number 3 which refers to the number 3 reactor in the plant.
Up to present there were 2 explosions in the plant and not 3.
Before commenting, try and understand the design and facts
http://bravenewclimate.com/2011/03/13/fukushima-simple-explanation/
There is no explosion. There will be one tomorrow though.
About 2 hours ago Tokyo Electric Co reported that they've decided to flood reactor #2 after its cooling died earlier during the day. It is not clear when and why it died. Anyway, since it died, flooding procedure was begun. However, they are so far failing to cover the whole active zone with water. TEPCO's official said that that is suggesting the reactor core has melted to some extent.
Just 10 minutes ago it was confirmed that water is flowing in slowly, and about half of the fuel is covered.
(theorizing, former nuclear control room operator here from a plant of the same style, GE Boiling Water Reactor, as the ones with the problem)
They've at a minimum lost coolant to relief valve operation after they lost cooling due to loss of offsite (and local emergency diesel) power. They possibly also have some pipe breaks within the drywell containment structure. The relief valve operation is a form of "zero power" cooling unto itself, but you need to make up for the lost coolant somehow.
Nearly all emergency procedures that have a chance of keeping the plant intact depend on power being available, without power, you have to resort to destructive methods (sea water pumped in via fire pumps for instance) to keep things cooled off. Note also, that the equipment that would normally reduce or eliminate hydrogen buildup (the apparent cause of the building explosions) also require power.
While the earthquake was the root cause, the seawater being able to reach and apparently shutdown the emergency diesel generators onsite is why the problems got MUCH larger than what could have been.
Also, I would be interested to know how much this thing could raise the temperature of the worlds oceans by, if at all.
You're a retard.
"I assumed blithely that there were no elves out there in the darkness"
Indeed. It would help probably the global set of journalists to just refresh this page every hour or so. It was obvious for quite a while that an explosion outside the third reactor was likely, since it was experiencing exactly the same sequence as the first reactor.
I live in Japan and have been following this news all day. The info in the headline and summary about the the reactors is complete incorrect. As to what has actually been happening:
First, the linked article is from 7 hours ago and is referring to the second explosion at Fukushima Daiichi of Reactor #3. The current situation as of 8PM Japan time was that the cooling system of Reactor #2 finally died and they just recently started filling it with seawater like the other reactors. This reactor is likely to cause another hydrogen explosion like the other two failed reactors before it. Also like the other reactors, this one may have suffered from some partial melting of its fuel rods.
Secondly, the article implies that thousands have died as a result of the problems at the Fukushima reactors. THIS IS NOT THE CASE! There have been reports of non-serious injuries and VERY mild radiation contamination but nothing that warrants any kind of panic yet.
Slashdot editors, please rewrite or delete this article, it is just spreading misinformation!
Yes, they could just drain off all the water completely (so no more steam generation and no risk of pressure build up) but it would totally wreck the core since it would melt into its concrete containment system, then you'd have a big, broken mess left over (although with all the radiation contained) that you'd have to clean up.
This way they are hoping the core is not totally wrecked (although it will definitely be damaged and require extensive repairs before being used again, if ever), so that it is easier to clean up and reprocess the fuel, with the problem that because you are pumping water in there (at less than required flow rate) it's boiling off quickly raising the pressure very high and cracking to H2 and O2, which just love to react very exothermically - causing those explosions we have seen when they vent this pressure out into the atmosphere.
The best case is that they keep doing what they're doing, and try to minimise the chance of H2 explosions, so that it will be easy to dismantle the core when it is cold. If they just let it melt there will be no more hydrogen explosions, but they'll have a molten mess of fuel and reactor parts spread out inside the concrete containment shield that will be considerably more annoying to clean up (but still completely safe from an external observer point of view - it;s designed to fail this way in the event of a full meltdown).
I think the problem is that everyone is equating "meltdown" to mean "will explode like Chernobyl", which is not what happened there - the Chernobyl explosion was a catastrophic steam explosion like a pressure cooker exploding. The core didn't melt down until after the explosion happened.
These "little" explosions we are seeing in Japan are because they are releasing the pressure in a controlled manner - if they just left it (and disabled the safety systems) then it could face a similar problem to Chernobyl, with the reactor being destroyed by a steam explosion, with the crucial difference that the core of this reactor is totally shielded (Chernobyl's RBMK reactors were too big to contain without it costing a ridiculous amount, so the building was the secondary containment structure - and it fell apart like tissue paper, as expected).
It's also slightly different in Japan - the reactor is "off" so the uranium fission reaction has stopped, and it's just residual heat and decay product heat to be dealt with, so it's a relatively slow and controllable heating. In Reactor 4 in Chernobyl, the fission reaction was very definitely running - but was poisoned due to neutron absorbing products (the core was running at much too low power), and when these were gone, and with the rods all the way out, the reactor spiked to a massive level which flashed all the water in there to steam almost instantly, which blew the lid off the top - just like throwing an aerosol can onto a fire, or shooting it with an air rifle. They had no time to relieve the pressure.