Mar
18
Japan’s Nukes – Scary or Interesting Concern?
March 18, 2011 | 6 Comments
Fast answer – an interesting concern. Those words are chosen as the human tragedy unfolds. Perhaps hundreds or thousands of people are exposed to the elements, including overnights in cold windy and wet weather. Thousands more have perished. The nuclear problems while serious in several ways are secondary shows. Food and shelter progress information is slow and tiny giving more concern and stirring painful thoughts and feelings. The Red Cross donation was done days ago. Thoughts and prayer continue.
Meanwhile the nuclear reactors are under control. The control rods seem to have been inserted – no runaway reaction has been reported. The worst fears never saw any chance to come into being. No meltdown in the unmoderated form took place and it seems not possible now. There is no Chernobyl event underway. Vast amounts of deadly radiation aren’t likely, almost impossible, but never say never. A deep blue glowing fire burning into the ground doesn’t seem to be a worthy forecast.
Fukushima Dai Ichi Nuclear Plant Damage. Click image for the largest view.
What has happened is the tsunami waves took out the ability to run cooling water over the working reactors and the spent fuel assemblies. When a reactor is suddenly shut down there is a tremendous amount of heat remaining in the reactor. There are tons of fuel, rod casing, control rods, apparatus, shielding, concrete and water at dry steam temperatures.
It takes a while for the heat to be bled off. Perhaps by the first of next week they’ll all be cool enough that simply residing in a pool would do.
There’s the next problem – even when under control some heat is made. Without a transfer out, the heat builds up until equilibrium with the surroundings is made. The question then becomes, will the equilibrium be cooler than the temperature required for fuel breaking out of the rod casings? Your humble writer doesn’t know, but is watching for someone credible to answer.
The things to watch for are the crews to get a fully rated cooling water flow underway and reliably running. The idea is to have no heavy elements escape. Water and light gases aren’t going to pose much if any risk. But heavier elements when driven to radioactively can give off the nasty rays. Actual fuel particalized or gasified and sent out would be tragic. It all depends on the answer of how hot the fuel rod assemblies get before equilibrium is reached.
That isn’t simple either. The roads and other access routes are shut down. Getting heavy equipment to the sites is a whole other challenge. These are big facilities; your pickup truck sized answer isn’t of much use. Railway support is still unanswered. Whole trains are reported as ‘missing’. Track damage is sure to be widespread. Road and rail are going to be needed for better than short-term quick fixes. And the quick fixes are going to be undersized in the best analysis.
A big helicopter should move some diesels and pumps. Water can be made to flow. The sources need set up and flow exits need made. While the reports don’t say, much is done and underway or the steam plumes, and emissions would be much higher.
It’s hard to get past the hysteria in the press. It makes for a bone chilling story for the un and ill informed. For the rest of us, a wish of god’s speed, good luck, decent weather and dedicated support are all we can do. The world can learn much, well engineered nuclear is safe, even in the face of a major earthquake when the engineering is done right.
There is also the lesson that earthquake preparedness isn’t enough after all. Tsunamis are also a factor deserving much more thought and attention. Redundancy in cooling while previously thought undefeatable was defeated by only a rise in water coming at great speed.
Mankind has harnessed one of physics great powers, the fission of atoms. The process, the exploitation and the use have decades of experience built up and better ideas on the drawing board. What is being learned isn’t that duly respected atomic nuclear power is dangerous in and of itself, rather it’s that the density of power, the mass involved, and the complexity haven’t been fully measured against the potential adverse impacts. The world just added or increased one more.
Energy in dense form isn’t going to go away. Whether it’s the explosive nature of gasoline or hydrogen, a lithium battery that could catch fire, an ultracapacitor delivering a huge shock, a wind turbine flying apart, or thermal solar panel fast cooking an interloper – eventually something will come along to make it dangerous and depending on how big the energy package is – might get hurt.
The main concern is to support the people working to secure the reactor and spent fuel sites. The first job though, is to find and care those without food, clothing and shelter.
Comments
6 Comments so far
Feedburner
Reddit
Stumbleupon
I am a long-time supporter of nuclear power, but this article is way too optimistic.
This is already more serious than Three Mile Island since it is clear that workers have been exposed to significant radiation, perhaps enough to affect their health, and there has been
widespread release of lower level radiation outside the plant, although comparisons with Chernobyl are at least for the moment exaggerated.
Here is an article and extensive comments which give an appreciation of the risks which in my judgement is far more realistic:
http://bravenewclimate.com/2011/03/17/fukushima-17-march-summary/
In brief there are two issues, the cooling ponds and the reactor cores.
The cooling ponds have no containment whatsoever, and may have cracks draining the water from them, although that is not clear.
If they become to a large degree exposed they will heat and release radiation so intense that pumping operations to cool the reactor cores will not be possible as approach would kill within minutes.
The reactor cores should when switched off cool rapidly, and as of last night should have been down to about 0.2% of running temperature.
However should cooling fail then they could heat up again to the point of re-criticality.
This might be because of radiation from the cooling ponds getting out of control and preventing pumping, but other problems are also possible.
They are using sea-water to cool, which of course contains salt, which the reactors were not designed to tolerate.
Not only has this ruined the reactors, but under the temperatures and so on in the reactor could lead to failure of some of the plumbing as parts fail, so stopping cooling.
It will take around another week before the cores have cooled enough if we can continue to get water to them for the danger of re-criticality in them to have passed.
I don’t know what the time-scales involved for the cooling ponds are.
We may get away with it, but the danger is still clear and present.
When the reactor was hit by a quake 7 times stronger than it was rated for – it survived and immediately shut down.
Backup desiel generators kicked on (since the plant was shut down it quit making electricity) and began pumping coolant until the Tsunami disabled them.
The plant switched to battery backup and coolant pumped for 8 hours until they were exhausted.
Emergency desiel generators were trucked to the plant – but there was no place for them to plug directly into the pumping system. So, heat rose and rods were damanged. Cooling water fractured into O2 and H2 and the H2 exploded.
Interestingly enough, if you sat outside the gates of the complex – you were exposed to radiation comparable to eating a lb of brazil nuts.
If you were in the nearby city – radiation exposure was comparable to eating 2 to 3 lbs of bananas.
Whether you subscribe to the glass is half empty or half full side of discussions, this situation highlights the need for continued research in to LENR/CANR. The hysteria being generated by Western media is feeding on the fears of the lay population and doing immeasurable damage to the nuclear energy arguement.
A pessimist says the glass is half empty.
An optimist says the glass is half full.
An engineer says the glass was produced with twice the necessary capacity.
Intriguing post. I have been searching for some good resources for solar panels and discovered your blog. Planning to bookmark this one!
Awesome post. I so good to see someone taking the time to share this information