Posted on 03/14/2011 8:08:53 AM PDT by EBH
The second hydrogen explosion in three days rocked a Japanese nuclear plant Monday, devastating the structure housing one reactor and injuring 11 workers. Water levels dropped precipitously at another reactor, completely exposing the fuel rods and raising the threat of a meltdown.
The morning explosion in Unit 3 of the Fukushima Dai-ichi plant was felt 25 miles (40 kilometers) away, but the plant's operator said radiation levels at the reactor remained within legal limits. Hours later, officials reported that fuel rods at Unit 2 were fully exposed at some point and may have been damaged.
Authorities have been pouring sea water into three reactors at the plant after cooling system failures in the wake of Friday's massive earthquake and tsunami, which is estimated to have killed at least 10,000 people. The latest explosion triggered an order for hundreds of people to stay indoors, said Chief Cabinet Secretary Yukio Edano.
(Excerpt) Read more at finance.yahoo.com ...
That happened last night our time- it’s now a little after midnight their time (Tuesday).
Meanwhile- in real time this just crossing the BBC:
1513: Water level in reactor 2 at Fukushima has fallen again, AFP now reporting citing Japanese media.
1507: Nuclear fuel rods have been exposed again at the Fukushima plant, Kyodo news is reporting. More on this as we get it.
Oh, there’d be combustion all right. Just not explosive combustion.
I mean, they could also vent them to the outside, but I presume that’s a gigantic no-no because of absolute prohibition aganst anything the slightest bit radioactive being able to get out of it’s impregnable cage.
Which is rendered less than impregnable by the explosion that results when too much H2 builds up. I mean, we now have some pretty clear evidence that this is a problem.
Anyway, maybe it won’t work. I guess, if it would, they would have thought of it already.
Read the information at the above link and your fears will be somewhat allayed. There are many redundant safety backups designed into such a plant, and they seem to be working in this case. I'd suggest that you hold your comments until after you have read the article. You will understand the situation better.
The drywall can’t be vented properly due to damage from the earthquake. Plus they still have power issues and valves have to be manually operated.
Everything that is happening needs to be kept in contest of the earthquake and tsunami damage too.
The best result will be this stuff is cooled or melts in place at this point.
Now, calm down.
“TEPCO continues to take all measures to restore the safety and security of the site and are monitoring the site’s immediate surroundings.”
There.
I used to work in the US nuclear power industry 30+ years ago before it went belly up. I’m more familiar with PWR’s, not the BWR’s used in Fukushima. Within the containment structures of PWR’s, hydrogen recombiners are installed in the upper chamber of the containment. I assume that these hydrogen recombiners were installed in the secondary containment at Fukushima. However, recombiners require an electric power supply to operate the fans to draw in the hydrogen/steam mix. In my opinion, with no power at Fukushima, the hydrogen just accumulated until an explosive concentration was achieved.
It means the local area had high radiation exposure. The rods are probably damaged. What this article doesn’t seem to indicate is if the rods were exposed still in containment or if the containment actually has failed.
Keep in mind the ‘hot stuff’ needs to hook up with particles in order to spread real contamination.
What they need to do now in the remaining plant is vent the roof. At this point, there’s no use in trying to save it, so hack a hole in the roof ASAP to get the H2/O2 to carry off without a build-up.
I'm as pro-nuclear as anyone, but I don't think putting nuke plants on shorelines is a great idea. I guess that was the beef with Diablo Canyon back in the '80's.
I don't know. Live and learn. The hysterics of left-wing politics means it's live and don't learn (because learning involves generalization, and generalization can be characterized as "stereotyping," which, in turn, leads to racism), but I digress.
It means don't worry about it. If you've been following the comments on the FR board yesterday, you'll know that this is nothing more than fearmongering by the anti-nuc left-wing media..
There ya go. As I said, if it'd work, someone's already thought of it.
I guess, if you lose power in a power plant, you're screwed nineteen ways from Sunday. That's pretty much all there is to it.
I have a question about using natural gas-fired power plants for base-load electric. Wouldn't the quantity of natural gas be too much to store at a power plant if it were used for base-load electric? Natural gas is not as dense as coal so I always thought that was why NG was used for peak-load electric. I'd think they would have to have many square miles of storage capacity if they use NG.
Japan is in the northern hemisphere which means its global opposite location would be in the southern hemisphere...maybe "The Brazil Syndrome".
I’m not sure it’s shorelines themselves, but it does seem clear to me that you shouldn’t put a plant where the required backup generators can be disabled by a tsunami.
Just as one of the lessons of Katrina is that you shouldn’t put your emergency backup generators in the basement below sea level, and you shouldn’t build your city’s required pump rooms such that they can be disabled by flooding if the city fills up with water.
In 2007, Japan had about 177 GW of conventional thermal electric generating capacity. According to Japan Electric Power Information Center, there are currently 60 thermal power plants, and 5 more are under construction: 2 using LNG and 3 using coal for generation. The country's aging oil-fired power plants are used primarily as extra capacity to meet peak demand, and less than 10 percent of electricity produced currently is oil-generated. The number of natural gas-fired power stations is increasing in Japan and roughly 30 percent of electricity is natural gas-fired. Coal remains an important fuel source and accounts for roughly 25 percent of electricity generation. Domestic coal production came to an end in 2002 and Japan imported 206 million short tons in 2008, for which Australia was the main supplier. New, clean coal technologies are being pursued in the power sector, however, in efforts to meet environmental targets.
Japan currently has had 54 operating nuclear reactors with a total installed generating capacity of around 49 GW, making it the third-largest nuclear power generator in the world behind the United States and France. EIA preliminary data shows that Japan produced 244 BKwh of nuclear-generated electricity in 2008. The government plans to increase nuclear's share of total electricity generation from 24 percent in 2008 to 40 percent by 2017 and to 50 percent by 2030, according to the Ministry of Economy, Trade and Industry.
http://www.eia.doe.gov/countries/cab.cfm?fips=JA
Natural gas is commonly used and pipeline connected around their country.
Thats hard to do in Japan. Over there its common for mountain ranges to rise up within 10-15 miles of the shore line. I guess it comes down to a dliemma betweeen locating the nuclear reactors in the mountains (where they could be affected by earthquakes, landslides and volcanoes) or near the shore (where earthquakes, tsunamis and pacific hurricanes can affect them). Considering that Japan has very little coal, oil or natural gas they are sorta' locked into muclear power.
Yeah, but if you didn't put them right next to the shoreline, you'd need pipes to bring the coolant to them. The environmentalists would have a cow over the pipelines.
Of course you can have cooling towers, but those are "grim symbols of nuclear horror."
Just as one of the lessons of Katrina is that you shouldn’t put your emergency backup generators in the basement below sea level, and you shouldn’t build your city’s required pump rooms such that they can be disabled by flooding if the city fills up with water.
Yeah, but if you put the generators anywhere but the basement, you've got vibration problems in the building's structure, as well as flammable fuel above the people, which raises troubling questions.
And if you put the fuel in the basement, with pipes to the upper floors, then water can get in the fuel during a flood.
It's really all just ignorance. People want the benefits of technology, of a technologically advanced society, but they don't want any risk, don't want to know about the risks or think about the risks. This makes puts the risks outside the realm of what the private sector can handle, because no one will want to bet on something that can ruin them if it goes wrong.
Thanks for the reply and info, Thackney. It must be expensive importing so much coal and natural gas every year. It makes sense though that they import LNG which does make the gas more dense for temporary storage.
http://www.eia.doe.gov/cabs/Japan/Electricity.html
Japan Electrical Generation (2007~2008)
Natural Gas 30%
Coal 25%
Nuclear 24%
Hydroelectric 9%
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