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Dismantling a Nuclear Reactor
AmiMoJo sends in a BBC story about the hardware used to decommission a nuclear reactor:
"The device cost £20m to design and build and will operate in highly radioactive conditions inside Dounreay's landmark Dome. Its detachable tool bits cost £100,000 each and weigh between 37-93kg. They will cut and grab 977 metal rods once used to 'breed' plutonium from uranium. ... Once in place, the device will operate in highly radioactive conditions and in a nitrogen atmosphere. Nitrogen prevents any residue of the liquid metal from reacting. Exposure to water or oxygen would cause the metal to catch fire. ... Up to three tool bits will be in use at any one time and can be replaced by another three carried in a special tool box without the need to remove the tool itself from the reactor. The rest of the tool bits will be stored above the reactor and would be fitted into place during service and maintenance breaks."
I, for one, welcome our detachable-bit, multi-pronged, nuclear-reactor-dismantling robotic overlords!
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
Are we talking about sodium coolant?
Tubal-Cain smokes the white owl.
I'm confused. Is this a "Ack, nuclear stuff is expensive and dangerous!" article or a "Wow, large engineering projects are cool!" article. Should I be AFRAID or IMPRESSED? I don't know!
Those who fail to understand communication protocols, are doomed to repeat them over port 80.
After all, the japanese managed to dismantle a reactor for free.
Too soon?
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
Something to rub real science in the face of the cargo cult fanboys that think reprocessing and decomissioning is easy and 1970's technology is all we need.
Small units, reuse of high grade waste with something like accelerated thorium, and actual containment of the remaining waste are the way to go instead of treating it all as a solved problem fixed by magic.
It would be awesome to see a "top kill" using nucular waste.
(Yeah, nucular)
lucm, indeed.
A repetitive dangerous task and, while I could say the obligatory "what could go wrong", often the robotic type of setup does better than people (simply because one doesn't have to worry about risk to self). I've seen this kind of thing before. They use them in commercial large scale breweries to clean the brew tanks (which is another dangerous and repetitive job for people).
What do you mean "hidden"? Nobody has ever denied that nuclear reactors eventually have to be dismantled, and, at least in the U.S., afaik, the operators of nuclear plants, BY LAW, are required to set aside funds starting the first day of operation, to decommission the plant when the time comes.
I don't believe decommissioning costs are some secret government subsidy. . .
This story is a bit misleading because the reactor being dismantled is an experimental fast neutron reactor. The materials it is made of were not really designed to be easily disassembled. This is different from a commercial light water reactor where part of the design requirements are being comparatively straightforward to dismantle.
Here they use an illegal alien in lead jockey shorts.
Sooo. We implement a technology (thorium breeders) that we have far less engineering experience with than the standard reactors and it will automagically instantly be better?
Uh. Who's doing cargo cult again?
(I favor thorium fueled reactors, but it will not automatically be a solution to all problems without further engineering and experience. Nothings easy.)
Oh, and are we talking about using 70s tech to clean sites up to 70s de facto standards of safe it, lock the place up and monitor it forever?
Or the massively more stringent modern ones requiring removal of all the radioactives and chemical contaminants?
The Japanese have built and used a similar tool for removing fuel from their troubled Monju fast breeder reactor prototype. The latest glitch was that the tool fell into the reactor and got stuck. The senior engineer on the effort committed suicide after this.
The tool was retrieved last month, after much effort.
It would be a shame if the Brits ran into similar problems, so hopefully they are talking to the Japanese and getting some lessons learned.
I assume you're trolling, but then again there's plenty of ignorant nuke haters in the world that can't possibly imagine that nuclear reactors are anything other than disguised nuclear weapons that will explode at any moment regardless of how carefully they're tended to.
I don't know about the UK, but in the US, the costs of decommissioning is baked into the fees paid by the plant owner to be allowed to build.
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The words "something like" were in there to provide a clue to the reader as to what the sentence was about. I think we should be moving on towards the future instead of pretending that the failures of the past are good enough, and I mentioned a promising lead so that idiots would not instantly assume that I'm against the entire concept of nuclear power for the hell of it.
It's very clear to all who take things seriously that the currently running reactors are just not good enough so the "engineering experience" argument unfortunately shows ignorance in this case. So what is your "standard reactor" that currently exists and that you think is good enough? Name it. You can't use the AP1000 as an example by your suggestion, it may be good enough but there is not yet a single completed reactor of that type so it's a step into the unknown instead of just "engineering experience". Thinking that civilian nuclear power is a solved problem is a massive step backwards and an example of that "cargo cult" where you revere the idea but want a thing that looks impressive instead of something that actually works.
The frustrating thing is that almost every reactor design more complex than a boiling water reactor has had serious problems. Most high-temperature gas-cooled reactors have had major problems, although Peach Bottom continues to generate power profitably. The German AVR reactor, which was a pebble-bed design, had a pebble jam and can't be dismantled at all. About a dozen sodium-cooled reactors have been built, with few successes and several sodium fires.
That's why reactors are still BWRs and PWRs. Everything else so far is worse.
To be fair the Dounreay FBR was not a bad design, it has been a very successful prototype and operated for many years. It can survive complete external cooling failure because of natural convection and many new designs are copying this idea. Although I do agree a liquid Sodium-Potassium mix is not a nice compound, and the newer designs are using better mediums.
While it has been theoretically in the process of decommissioning since 1977, it has started and paused many times, mainly for good reasons like allowing more decay time. They are currently removing the cooling medium and this will take a couple of years, in my opinion they are working slowly and safely, which I'm sure you'll agree is the right way.
Anybody know how much it costs to decommission such a reactor (or similar)? I'd heard it's a pretty costly business. A few hippies I know have his theory that the total life cycle cost of commissioning, running, and decomissioning a reactor is more than the value of the electricity produced in its lifetime. But I'd love to get some figures before arguing further with them. Any thoughts? How long / how much does it cost to decommission a reactor of this type (or similar)?
...people who are not nuclear engineers talking about why nuclear engineers are Doing It Wrong.
Next week, Bricklayers wonder about space.
This story is probably highly misleading but I would still give it a 5-star rating just for being so /.
The "cargo cult" was a expectation that the form of something would produce results without any of the hard work of knowing anything at all about the function (fake military infrastructure in the Pacific Islands to get supplies to turn up by magic). Get something to about the right shape and it's good enough and the rest is magic not worth bothering about. Thus I apply this label to the people that are unquestioning fans of something but get quite irate when practicalities are discussed in any way apart from mindless cheering - if you dare to suggest a problem or difficulty you become a sworn enemy. It's a behaviour that you can see here on a few topics and nuclear is one that brings such fanboys out. Just mention some way of dealing with nuclear waste (eg. synrock) and you are bound to get one or two of them that push some line of counterproductive magical bullshit such as "nuclear waste does not exist". Such idiots in government killed off some promising nuclear research designed to overcome problems that such fanboys wanted to pretend do not exist. US civilian nuclear technology would still be stuck in the 1970s due to that attitude if there had not been a purchase of technology from Toshiba in Japan where such an attitude is not as widespread.
It's yet another disturbing manifestation of something that is almost a hatred of science despite a love of technology.
Back to thorium breeders and similar designs, there's a potential there to melt down expired fuel from old reactors instead of having to do all of that difficult reprocessing. That's one of several good ideas that are a long way ahead of the 1970s technology that is currently in operation.
When I was in high school, I did a week's work experience in the computing department at Dounreay
We worked on the ground floor of the building that houses the old DFR control room (it was just upstairs from us). We were right in the shadow of the spherical reactor housing (affectionately known as "the Golf Ball".
They had all sorts of old tech in their computing department - DEC VAX systems, racks full of old Gandalf kit, etc. It was 16 years ago now, and I can't remember what else they had in there. There was also just about the biggest and noisiest line printer (used for printing payslips) in an adjoining room.
My mother also worked as a contracts officer on the Dounreay site for many years.
We lived in a nearby town called Thurso, which was a small fishing port prior to Dounreay's construction. The town literally doubled in size during the 1950s as construction on the Dounreay plant began. The UKAEA was Thurso's biggest employer. Since the plant stopped generating power (in the mid 1990s), the town has stagnated and the population has been gradually declining. There's nothing up there (employment-wise) to attract newcomers any more.
He's Jesus, for Christ's sake.
Gee for windmills all you need is a wrench
"It's very clear to all who take things seriously"
There's an old joke that when you see a phrase like that in a paper, it means "I think so."
The biggest problem with the currently running reactors in the US is that promises that were made about storing, reprocessing or otherwise dealing with the waste were unfullfilled here.
Purex processing wasn't an ideal solution, but was a possible one. It was made impossible for political/arms control reasons.
Entombment at Yucca Mountain wasn't an ideal solution but was a possible one. It was made impossible due to the majority leader of the senate being from the state it's located in.
Going to a more advanced fuel cycle like the Integral Fast Reactor and pyroprocessing wasn't an ideal solution, at least partly because there was still a good bit of engineering work that needed to be done on it. But, it was a possible one. That work was cancelled, because as Bill Clinton said in his first state of the union address "We will never need it.". (It'd be nice if that were followed up on again now that we know "we might need it".)
If you have to have an example, SNUPPS was largely "good enough". Ditto CANDU. The EPR may be "good enough" but obviously like AP1000 isn't online yet, so we don't know. We'll see how the ones that are in construction do after the current delays.
Ideal? No. But if you want perfection, you better stick to studying mathematics or divinity.
So, if that makes me ignorant in your eyes, so be it. It's interesting that you so blythely call people ignorant about nuclear power when you apparently had no idea France was still actively reprocessing commercial fuel and thought they'd stopped in 2005 (as pointed out in another part of the thread).
As to thinking nuclear power is a solved problem: Do you usually try arguing against positions that someone else didn't take? Can I put words in your mouth too?