Accelerator Driven Treatment of Nuclear Waste

quax writes "In the wake of the Fukushima disaster the nuclear industry again faces massive opposition. Germany even decided to abandon nuclear energy altogether and the future of the industry is under a cloud of uncertainty in Japan. But one thing seems to be here to stay for a very, very long time: radioactive waste that has half-lives measured in thousands of years. But there is a technology under development in Belgium that could change all this: A sub-critical reactor design, driven by a particle accelerator can transmute the nuclear waste into something that goes away in about two hundred years. Could this lead to a revival of the nuclear industry and the reprocessing of spent reactor fuel?"

Comments

1,000 year? 200 year? Who cares.

[Anonymous Coward]

I'll be long gone by then. Let someone else deal with it. Don't waste a cent of my money on it.

More importantly...

[Anonymous Coward]

If we can fundamentally change the material to be more active, such that it decays in an exponentially shorter period of time, is there marketable energy potential to be realized in our nuclear "waste"? Such potential could drive industry to clean up its own mess.

Re:More importantly...

[man_of_mr_e]

More importantly, how much energy will it take to do this? You are effectively destroying the efficiency of the reactor if you then have to turn around and reprocess it with more energy.

Re:More importantly...

[Rei]

That's my question as well. And beyond that, if you *can* be energy positive using a subcritical reactor, why use a critical reactor at all? Oh, sure, free neutrons are nice and all, but if the cost of getting them is meltdown risk, an angry public, and a huge, ever-growing burden of protective measures and waste disposal costs...

Re:More importantly...

[quax]

Producing fast neutrons is not that simple. It either requires a critical breeder type of reactor or a powerful particle accelerator.

For the longest time the latter where high tech custom build experimental devices for physicist to play with. Only recently have we gotten to the point where you can order one "of the shelve" for instance from Siemens for medical purposes (e.g. ion irradiation of tumors as a more targeted alternative to chemo).

Re:More importantly...

[rufty_tufty]

If we can fundamentally change the material to be more active, such that it decays in an exponentially shorter period of time

This is already the case. If it's highly radioactive and therefore dangerous then it decays in a short amount of time. Conversely if it's going to hang around for thousands of years then it cannot be very dangerous.
The problem is that the dangerous stuff is mixed up with the safe stuff. If re-processing were legal/economical then there would be no problem.

or, they could bombard it with neutrinos..

[wierd_w]

Wasn't it recently discovered that neutrino interactions with unstable neuclei causes an increased rate of decay?

Placing the waste near a particle accellerator that generates large quantities of neutrino emissions should reduce the time needed for those waste products to decay.

The neutrino emissions themselves are harmless to living things. You get uncountable numbers of them passing through 1cm of skin every second from sunlight. (Even if you are indoors!)

Re:or, they could bombard it with neutrinos..

[ericloewe]

Why waste the perfectly good stuff when it could be used to fuel other reactors that "burn" them into progressively more innocuous things (as in, half-lives of a few years instead of millenia).

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

Uh, material with a half-life of a few years is hardly 'innocuous'. That's what we normally call 'crazy freaking radioactive'.

People seem to have this bizarre idea that a long half-life makes something dangerous, when it's precisely the opposite.

Re:or, they could bombard it with neutrinos..

[sjames]

It is innocuous in terms of waste management because however extremely dangerous it is in the short term, it soon becomes inert.

Re:or, they could bombard it with neutrinos..

[alexander_686]

You might want to take a look at the article.

First, it uses the Thorium fuel cycle. Consider your slant I would think that was a plus.

Second, they are not talking about “perfectly good“ fuel – they are talking about heavy metals. Most of the waste, by volume, are not the fuel rods but more humdrum stuff, like metal pipes. Not usable for fuel but still very radioactive for a long time.

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

Uh, no it doesn't work that way. The reason neutrinos are "harmless" to living things is because they're so fucking lazy to interact with anything. Including living matters or atomic nuclei, radioactive or not.

In other words, if we could generate a beam of neutrino strong enough to change the property of materials in front of it,
(1) it will take a ginormous amount of energy, probably not available to mankind in any near future,
(2) it won't be "harmless to living things" any more.

Re:or, they could bombard it with neutrinos..

[mellon]

Not strictly true. Suppose you have a source with a half-life of 200 years, and you have a ton of it. In 200 years, half of that ton will still be radioactive. In 200 more years, a quarter. And so on. So its not like 200 years later, it's all gone. The trouble with the long half-life stuff is that although it isn't radioactive enough to kill you outright, it's more than radioactive enough to cause cancer, and it'll keep doing it for a lot longer.

The sad thing about all this is that of course there's a lot of potential energy in a radioactive isotope, at least potentially. So if we succeed in releasing that energy quickly and in a way that doesn't capture it, future generations may look back on and curse us for doing so. Just because we can't get our act together to keep our nuclear plants safe doesn't mean they won't figure out a way to do it.

Re:or, they could bombard it with neutrinos..

[wierd_w]

Neutrinos are weakly interacting, yes. That is why they are harmless.

I am not proposing doing the prticle collisions that would produce the added neutrino flux JUST for the purposes of waste decontamination, but for scientific purposes. The waste is simply housed nearby to collect on the synergy of the neutrino production. Like any radiant energy source, concentration falls off on an inverse cube with distance, especially for something as electically charge-inert as neutrinos. You don't ramp up flux production, you move the items closer to the flux source.

You don't need to increase the rate of decay by orders or magnitude, just slightly. Continual exposure would have cumulative effects that would be equivelent to years of storage, when the materials being exposed are already very low level waste.

I am not proposing building a device that produces more neutrinos than the sun. I am proposing the placement of low level waste near existing colliders to have very near exposures for cheap.

If the headline approach is used, the subcritical fission would release such neutrinos as well.

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

Uh, material with a half-life of a few years is hardly 'innocuous'. That's what we normally call 'crazy freaking radioactive'.

People seem to have this bizarre idea that a long half-life makes something dangerous, when it's precisely the opposite.

That depends on how you count "dangerous" of course. Something that is very, very hot for a few years is much easier to deal with than something that is merely very hot but remains so for a few hundred years.

Re:or, they could bombard it with neutrinos..

[sjames]

Ideally, we would separate out the actinides (and so the stuff that makes people wonder how we will store 'waste' for thousands of years) and use them for fuel in conventional reactors. That leaves us the much hotter stuff that could economically drive a low temperature turbine for years without significant interaction.

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

no, you'd need a chemical processing plant to scrub the daughter isotopes out while pumping in hot stuff.

What you really want to do with it, is vitrefy it and dump it back where the uranium came from in the first place. Which is to say, deep underground, where it's not coming back up until long after it burns out.

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

I don't think you understand anything that you have just said.

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

Assuming the variations seen in radioactive half-lives were measured correctly, and actually are the result of the attributed effect of neutrinos, the effect is still very, very small, a fraction of a percent. Additionally, the effect is only seen in specific isotopes, as there have been other isotopes measured with no effect seen. Plus, one of the best sources of neutrinos we have now is a nuclear reactor, where a 1 GWe reactor may be putting out 100 MW of anti-neutrinos (although much less of normal neutrinos). Using accelerators to produce neutrinos can expect some serious efficiency issues, since it would involve creating high energy protons to get pions and/or muons for production of neutrinos. There is work being done, but most of it seems to be toward generating high energy neutrinos that are a bit easier to detect.

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

A 1% change in the half life would mean you would "burn" 1.01% extra material after a single (original) half life period. The cumulative effect would be quite small short of a much, much large change in half-life. In other words, if the original half-life was 100 years and you needed to wait 10 periods (1000 years) to get to a safe level, the one percent change would mean you now have to wait 990 years. And that 1% is much larger than the purposed changes seen due to neutrinos, and would require the neutrino source to be running the whole 990 years.

Re:or, they could bombard it with neutrinos..

[wierd_w]

Ok. Let's do a little thought experiment.

We have iron piping that has been exposed to high levels of alpha decay biproducts and heavy neutron exposures; they were the pipes that recirculated primary coolant in an old style reactor. They are hot, but won't decay to safe levels for a very, very very long time. You can't burn iron in a fission plant. Treating it in a breeder reactor would be retarded.

What to do with it?

We have very high energy colliders that produce neutrino beams used for scientific exeriments. The expense of running these colliders is offset by the scientific discoveries they make. When the neutrino emissions aren't being directly used, they can be used to treat these difficult to deal with waste materials.

Radioactive iron, such as these hypothetical pipes, decays VERY slowly. It can take years for a single atom to undergo spontaneous fission, and decay. (Perhaps hundreds of years.) Even if the rate of neutrino exposure was so low, that it impacted rate of decay by .0001%, it could result in several years of storage shaved off the time needed to decay to inertness.

The density of the neutrino flux falls off in the inverse cube of distance, like light, and other forms of radiation. It radiates evenly, because it is not disrupted by magnetic fields nor by interaction with matter in a meaningful fashion.

As such, the closer you plce the radioactive object to be exposed, the more neutrinos it will encounter. Even though the rate of neutrino interactions, as rated by percentage of neutrinos produced interacting with the target, does not change, the number of neutrinos per second does. This is why moving the material very near the source has an effect.

You don't need "black hole quasar jet-like neutrino emissions". You just need passive exposure to a strong source, using close proximity to that source.

We aren't trying to break down plutonium. That is better taken care of in a power plant's reactor. We are trying to reduce the time needed to sequester the low level waste.

Re:or, they could bombard it with neutrinos..

[sjames]

Actually, you wouldn't as long as you accept that the output will decline over time. When the output declines enough, re-processing again might be useful. However, the big improvement is that it makes the highly radioactive material into an asset rather than a liability. People are inevitably more careful managing assets than liabilities.

Re:or, they could bombard it with neutrinos..

[wierd_w]

The original story was to run a high energy collider for the purposes of enriching waste, so that it is less stable, and decays more usefully/safely.

This collider *would* be a long term installation.

Perhaps not active the full 1000 years, but also could be run under less.. precise... conditions. Collisions favoring neutron emission and neutrino emissions would favor both uses.

The high level waste could be reprocessed, and low level waste could be passively exposed to 'above normal' neutrino flux for extended periods.

It isn't a magic bullet, and I don't claim it is. It is just one of many small things that can be done to assist decontamination.

Re:or, they could bombard it with neutrinos..

[Anonymous Coward]

Assuming the effect attributed to solar neutrinos also works for GeV muon-neutrinos, typically the largest component produced by accelerators used for neutrino production. And assuming it doesn't care that the flux of such sources is a billionth of the flux of solar neutrinos (for the MINOS experiment at least).

Even if the rate of neutrino exposure was so low, that it impacted rate of decay by .0001%

You might want to check your math here. Decay rate is proportional to your starting quantity and inversely proportional to the half-life. A 0.0001% change in decay rate is going to be pretty close to a 0.0001% change in half-life. You would need to store something for some number of half-life periods depending on how much you start with, regardless of temporary half-life changes, so a 0.0001% change in half-life will change the total storage time by 0.0001%. The only way that will make a difference of years is if you were originally going to store the material for millions of years, and instead expose it to an appropriate neutrino source for the whole time (once again, assuming the neutrino effect works as desired too).

Two other minor things:

The density of the neutrino flux falls off in the inverse cube of distance, like light, and other forms of radiation.

Square, not cube

It radiates evenly, because it is not disrupted by magnetic fields nor by interaction with matter in a meaningful fashion.

For beams it isn't evenly, but determined by the momentum of the parent particles which are heavily collimated. But even a collimated beam would still follow the inverse square effects, so this is a rather minor correction too.

Re:or, they could bombard it with neutrinos..

[lister king of smeg]

One wonders could they not melt down the pipes and use a centerfuge system like the do with uranium to seperate the hot metel from the stable

Re:or, they could bombard it with neutrinos..

[nojayuk]

Your initial supposition is basically wrong so the rest of your argument falls apart rather.

The materials in a nuclear reactor structure exposed to high levels of neutron and gamma flux are chosen so they don't activate easily or indeed at all. For example the steel alloys used for the reactor vessel don't contain cobalt as Co-59, the most common isotope plus a neutron produces the very radioactive isotope Co-60 with a short halflife of five years producing an intense gamma ray on decay. The fuel rods are jacketed with zirconium for similar reasons since it is pretty much transparent to neutrons. The result is that after a BWR or PWR has been opened for refuelling and the hot fuel rods removed the level of radioactivity within it is miniscule and people can work around and even inside the open reactor vessel (once it has been drained) with minimal protection.

Decommissioning a reactor is carried out either quite quickly after the reactor is shut down for the last time e.g. the Japanese Tokai 1 Magnox reactor which was reduced to brownfield status in about ten years or the alternative process employed by the British for its older Magnox reactors is to remove the fuel rods, demolish the rest of the site (turbine halls, control room etc.) and mothball the reactor building, leaving it for eighty years or so for residual radiation to decay to the point where the future demolition job has no radiation problem to deal with at all.

The long-term radiation problems with reactors really only accrue from the fission products and some of their daughters in the spent fuel rods. Separating them out for vitrification and geologic burial is a solved problem -- it costs money to carry out but it reduces the volume and mass of true waste quite substantially while returning 90%+ of the original fuel rod material to the fuel cycle. The US for political reasons does not reprocess fuel rods and the bulk and mass of the resulting stockpile is starting to become problematic hence the Yucca Mountain project and its political aftermath.

Re:or, they could bombard it with neutrinos..

[ozmanjusri]

Which is to say, deep underground,

I don't think you understand what a uranium mine is.

Please do a Google image search for "uranium mine", then reconsider what you've just posted.

Re:or, they could bombard it with neutrinos..

[dido]

From what I understand the process that causes neutrinos to speed up radiocative decay is the result of inverse beta decay (I'd link to a Wikipedia article but WP thinks that the term 'inverse beta decay' is synonymous with electron capture. There seems to be no independent article for this process I refer to, despite the fact that this process was used in the Cowan-Reines experiment that was the first conclusive evidence for the neutrino, and won for Frederick Reines his share of the 1995 Nobel Prize in Physics!). Anyway, if you had neutrinos energetic enough to make this process frequent enough (never mind that doing this is very difficult), these neutrinos would then hardly be harmless to living things. They're only harmless to us because the interaction cross section for the vast majority of neutrinos is so small, and so their chances of interacting with ordinary matter so remote as to be almost nonexistent: you could send a neutrino of typical energies through light years of solid steel before it interacted with anything. If you could somehow produce a neutrino beam that was of high enough energy, it would readily transmute normal matter in its path: an antineutrino beam would turn protons into neutrons, and a neutrino beam would turn neutrons into protons. If you had hydrogen (e.g. in water), you would get high-energy free neutrons, and that is the way to increase the radioactivity of something, not decrease it!

Re:or, they could bombard it with neutrinos..

[quax]

The article on that can be found here. It is not settled science that this effect is real, and it is a very small effect. That neutrinos may be causing this is conjecture at this point.

What makes the effect exciting is that it'll hint at new physics if confirmed.

Re:or, they could bombard it with neutrinos..

[Neil Boekend]

More importantly: something that has a short enough half life can be used as a powersource. Just stick it in about the same design as a normal modern nuclear facility and boil some water!

Re:or, they could bombard it with neutrinos..

[delt0r]

200 years is not a few years. Most of the activity is from things with half lives well below a century. Assume you reprocess and burn Actinides.

Re:or, they could bombard it with neutrinos..

[overmod]

>If you could produce a neutrino beam of high enough energy...

I presume you mean high enough DENSITY. As with the photoelectric effect, you have two variables: energy and density. Guess which is more significant to a particle with so little interaction?

We won't go into what is required to produce a neutrino flux of 'appropriate' density to work for effective transmutation (we'll leave aside the question of *cost-effective* transmutation for another time) -- Greg Bear has mentioned one prospective source in Anvil of Stars. (But his source might be a wee bit impractical for working with terrestrial nuclear waste!)

Re:It's not "spent"...

[Anonymous Coward]

Well, fuck it all. I meant "It's not 'spend'...", but I fucked it up. This invalidates my rant entirely, and "spend" is now retroactively the correct past tense of itself, just to put me further in my place.

Well, it hasn't yet.

[Anonymous Coward]

This is not a new idea.

But anything that can transmute nuclear waste can be used to breed plutonium (or potentially other weapons-usable fissiles), so certain world powers would rather we sit the waste in a heap for a few thousand years. Until you fix the political problem, no technology, new or old, will lead to "a revival of the nuclear industry and the reprocessing of spend reactor fuel".

A step

[Quantus347]

Its a step in the right direction, but it wont gain any sort of sustainable foothold until the technology can get the half-life of the waste down to within a single lifetime. In truth, what it really needs to accomplish is a technology that actually breaks even: something that reduces the stockpile at at least an equal rate to what our nuclear power use is producing.

Either that or productive Fusion, which does not produce near the lasting Radioactive waste.

Re:A step

[Hatta]

If we can convert long half life materials to short halflife materials, would those short halflife materials provide enough decay heat to harvest energy from? Why not hook a turbine up to the waste pools and get some useful work out of that?

Re:A step

[dargaud]

I'm the guy who write the software for the reactor (and the accelerator) of TFA. And yes, it run Linux, on embedded Xilinx cards with custom FPGAs. I can't vouch for the ability of the system to transmute long-life waste in a semi-industrial way as it's only a research reactor, not even a demonstrator. But it's the 3rd prototype of its kind and it's working well enough. More information is available here in french, and, as a long time /. member, if you have questions about the control/command software, I'll be happy to answer when I wake up in the morning ! Yeah, the name of the experiment is somewhat confusing: Genepi/Guinevere/3C/Venus/Ganddalf. One is the accelerator, one is the reactor, one is the data acquisition, one is the combined experiment... I get lost too.

Re:A step

[Anonymous Coward]

In truth, what it really needs to accomplish is a technology that actually breaks even: something that reduces the stockpile at at least an equal rate to what our nuclear power use is producing.

But the nuclear waste stockpile already exists. It is a sunk cost, it's not going away even if we abandon all nuclear power.

Waiting for a negative-waste power reactor design is like waiting for cars that actually sequester carbon as they run. It's not too practical, and maybe the job ought to be done by some more-specialized device.

Re:A step

[quax]

This is really neat. So is the current control software in Mol using your code? Will MYRRHA use the same code base or does it require a complete re-write?

Are you using a real-time kernel?

What kind of quality control are you using to ensure the software performs exactly as designed?

Are you using a functional programming paradigm?

Are the reactors computer systems networked to the outside world? If so what kind of security measures do you have in place to safeguard access?

Is your software a critical component of the control feedback loop e,g. reduces beam intensity based on the measured neutron flux? If so what kind of redundancy is build into the system?

Re:A step

[Anonymous Coward]

Either that or productive Fusion, which does not produce near the lasting Radioactive waste.

Additionally, there are various Fusion-Fission hybrid schemes where the neutrons from a fusion reactor are used to reprocess and/or clean waste from fission reactors. You might have half a dozen fission reactors to every fusion reactor, and there are various plans that would work even if the fusion reactor was a net energy loss used just for waste processing.

Re:A step

[Lucractius]

How does a person get into this area without dropping their job, moving to the other side of the country to the only University that has a good Nuclear Physics program and spending forever getting a PhD and kicking off a research project on my idea?

I've had my own high level schematics drawn for this kind of idea years ago using practically off the shelf parts, i keep the construction price updated every year or whenever i spot new developments that would change things.

The reason its not built already and destroying test samples from smoke alarms to prove it works, is 3 things
Price... most parts arent cheap when your dealing with radioactive anything. general rad hardness & reliable material properties under neutron bombardment is hard to get.
My basement isnt safe enough... Obviously.
And that without the magic voodoo bureaucracy navigator to avoid the fact without almost impossible to obtain permits, I'd be breaking a boatload of laws many of which would probably create a terrorism scare soon as the media saw the report, because people wont think far enough to understand the difference between trying to transmute down to non radioactive material and making things more dangerous. Since Australia has remarkably thorough nuclear regulations. They basically say dont do anything to do with nuclear material unless we say you can, then define nuclear material as anything radioactive. Its loophole free from what I can tell, no room unless your backed and sanctioned. Which is why I havent done more than draw the plans.

Would love an insiders perspective on how hard it is to do research in this area... What are your thoughts on the glacial pace of innovation in the nuclear industry. While it has to be done safely, I don't think it should take 25 years to tinker with small ideas like this sort of stuff.

Re:A step

[Anonymous Coward]

I read some where or had heard that some company was trying to develop a reactor that would be able to use spent fuel? An all molten chamber. I would seem this idea has not played out or has it been abandoned?

Re:A step

[quax]

This is the concept of a fast breeder critical reactor. Only Japan was still attempting this. Had a nasty accident, and after Fukushima probably no future.

Re:A step

[Intrepid imaginaut]

Correct me if I'm wrong here, but don't shorter half lives mean the material is much more dangerous? I mean do we really care that something has a half life of four hundred thousand years if its just a notch above background radiation levels, and less than the background level naturally in many places?

Re:A step

[dargaud]

This is really neat. So is the current control software in Mol using your code?

Yes.

Will MYRRHA use the same code base or does it require a complete re-write?

Myrrha is only a concept so far: no development yet. It will most likely be a complete rewrite looking as to how far the code has diverged from the original specs.

Are you using a real-time kernel?

No. Everything that needs to be real-time is done on FPGAs and then transmitted to the kernel and user app via GPIOs.

What kind of quality control are you using to ensure the software performs exactly as designed?

Basically years of testing. Anyway, since it is a subcritical reactor, the security requirements are much less stringent. Some purely security stuff (read: not the control/command and or acquisition), is handled by other systems which have no interaction with mine. And as for the original 'design', well, it is research, meaning that specs start from a white sheet and build from there as we add pieces to the machine.

Are you using a functional programming paradigm?

All in C.

Are the reactors computer systems networked to the outside world? If so what kind of security measures do you have in place to safeguard access?

They are indirectly accessible (2 sets of firewalls). Like I said it is a research system with much less stringent security requirements, and quite a few researchers work on it and need remote access.

Is your software a critical component of the control feedback loop e,g. reduces beam intensity based on the measured neutron flux? If so what kind of redundancy is build into the system?

One set of software runs on the cards themselves: a minimalist BuildRoot install with a basic software that does as few things as possible (transferring acquired data to the network, reacting to commands from the Control/Command, sanity checks, basic security, going into security mode in case contact is lost, ...). One or more linux PCs run the C/C software and communicate with those cards and tell them what to do. If this soft crashes, nothing actually happens, the system keeps running for a while. You can actually shut down one PC and start another and everything keeps running like nothing happened.

But all the 'real' security is done in hardware: thermal shutdowns, beam intensity shutdowns, etc... It's actually difficult to turn the system on: everything has to be just right and there are plenty of little things that do stop the process.

Re:A step

[dargaud]

How does a person get into this area without dropping their job, moving to the other side of the country to the only University that has a good Nuclear Physics program and spending forever getting a PhD and kicking off a research project on my idea?

Well, there are 3 domains: military, industrial and research. For the first two, yes, you need to have worked into the right university and then entered the right industry. I doubt there are side entrances but I don't know much about them. As for research, where I work, I got in after 15 years of working in atmospheric science. I'm just an engineer that builds acquisition systems, so there's not much of a difference to me. There are a lot of people that come and go at the lab but they are either associate researchers from other institutions coming for a time, or students at varying levels. In your case the only way I can think of would be like mine: get in via a technician / engineer recruitment, and then show that you have ideas and try to get a project off the ground with the help of interested researchers.

Re:A step

[quax]

Thank you very much! Very interesting stuff.

Two follow up questions:

How many coders have been working on the software?

What kind of version control system do you use?

(BTW your site www.gdargaud.net rocks!)

Re:A step

[Anonymous Coward]

See this.

Re:A step

[dargaud]

Thank you very much! Very interesting stuff.

Two follow up questions:

How many coders have been working on the software?

What kind of version control system do you use?

The bus factor is 1 for the software and 2 for the hardware. A lot more people work on the mechanics and obviously on the research. I use SVN.

(BTW your site www.gdargaud.net rocks!)

Haven't updated it much recently. It's a lot less photogenic to do nuclear software than polar software...

Re:A step

[assertation]

Its a step in the right direction, but it wont gain any sort of sustainable foothold until the technology can get the half-life of the waste down to within a single lifetime.

Any toxin/poison that requires long term human management for containment is not suitable. Sooner or later people fuck up, cut corners or get corrupted.

The nuclear power industry has to come up with a process of making nuclear waste inert in under a year.

Re:A step

[mcgrew]

Correct me if I'm wrong here, but don't shorter half lives mean the material is much more dangerous?

No, it means the material becomes inert faster.

Re:It's not "spent"...

[Anonymous Coward]

You do have to admit, it's pretty easy to confuse "spent" with "spent." Both are spelled the same. Sound the same. Both can even be used as the past tense of spend. But, alas, most just don't get the intricacies in the differences between spent and spent.

Thanks for clarifying.

Cue the hippies

[ericloewe]

"Nuclear is bad for everyone!"

Compared to what? Coal and natural gas, that are bad for us even when they're within normal parameters? Renewables that are nowhere near enough to properly replace what we're currently using without using up massive land areas?

I'll take a nuclear reactor in my backyard over a natural gas plant in my neighborhood or a coal power plant within a 20 km radius any day.

Re:Cue the hippies

[CrtxReavr]

Yes, everyone's so worried about the disposal of the spent nuclear fuel rods, while coal ash is scattered to the wind with reckless abandon: http://www.scientificamerican.com/article.cfm?id=coal-ash-is-more-radioactive-than-nuclear-waste

Re:Cue the hippies

[Anonymous Coward]

Nuclear waste can be very entertaining -

http://www.youtube.com/watch?v=cmfJpq8pOV0&feature=relmfu
http://www.youtube.com/watch?v=K2QWiBiaqCQ&feature=related
http://www.youtube.com/watch?v=3gbc1dJNQgM&feature=relmfu
http://www.bellona.org/subjects/Lepse
http://www.youtube.com/watch?v=4XMfPIfk8xo&feature=related

Re:Cue the hippies

[Anonymous Coward]

How big is your backyard???

Re:Cue the hippies

[Anonymous Coward]

When you're living 2,000 years old and stuck in the same neighborhood make that same argument. Otherwise who gives a shit? Plenty of people are happy to destroy their environment for others at personal gain.

Re:Cue the hippies

[Hatta]

It's true, many on the left are overly skeptical about nuclear power. But at least liberals change their opinions when educated.

Nuclear power is a classic test case for liberal biasesâ"kind of the flip side of the global warming issueâ"for the following reason. Itâ(TM)s well known that liberals tend to start out distrustful of nuclear energy: Thereâ(TM)s a long history of this on the left. But this impulse puts them at odds with the views of the scientific community on the matter (scientists tend to think nuclear power risks are overblown, especially in light of the dangers of other energy sources, like coal).

So are liberals âoesmart idiotsâ on nukes? Not in Kahanâ(TM)s study. As members of the âoeegalitarian communitarianâ group in the studyâ"people with more liberal valuesâ"knew more science and math, they did not become more worried, overall, about the risks of nuclear power. Rather, they moved in the opposite direction from where these initial impulses would have taken them. They become less worriedâ"and, I might add, closer to the opinion of the scientific community on the matter.

You may or may not support nuclear power personally, but letâ(TM)s face it: This is not the âoesmart idiotâ effect. It looks a lot more like open-mindedness.

Re:Cue the hippies

[mellon]

Generally speaking you will find that the same people who oppose nuclear also oppose coal, for precisely the reason you state, as well as a few others—e.g., mountaintop removal, watershed destruction, deforestation. In fact, in general at this point I think you will find that people who oppose both oppose coal more than nuclear. But it's not an either-or proposition—despite widespread naysaying, it turns out that renewables really can work. What we lack is not the technology, but the ability to wean people who depend on extractive industries for a living from the dark teat.

Re:Cue the hippies

[ericloewe]

That's a very nice concept. In practice, no nuclear means more natural gas and more coal, which will inevitably have ill effects on us, while nuclear is safe if correctly handled.

Re:Cue the hippies

[Medievalist]

Compared to what? Coal and natural gas, that are bad for us even when they're within normal parameters? Renewables that are nowhere near enough to properly replace what we're currently using without using up massive land areas?

Well, personally I'd just use enough renewables to properly replace what we're currently using, since we have tremendous land area available - hundreds of thousands of times the area actually required to power the world, in fact, even using fairly old technologies.

But don't let me get in the way of your anti-hippy rant, I can tell it's very meaningful to you. Please carry on.

Re:Cue the hippies

[Qzukk]

Now, now, they don't just let coal ash scatter to the wind, they keep it in big ponds in your living room.

Re:Cue the hippies

[JoeMerchant]

Germany is full of highly reactive Green sentiment, they'll do just about anything "Green" without regard for the actual consequences. High school yearbook? make it from recycled paper that disintegrates in less than 5 years. Nuclear power? abolish and replace with coal. Stuck waiting for train crossing for more than 5 seconds? Shut down idling engines (debatable, but when first instituted stop/restart cycles ultimately causing more pollution than the idle due to increased maintenance / decreased engine life, especially on the oh so popular Golf diesels.) Solar panels on roofs - because you can tell they're "Green", regardless of the energy expended in making them and their load leveling batteries, inverters, etc.

Re:Cue the hippies

[Anonymous Coward]

With the exception of Geothermal or tidal power both of which are location specific, renewable energy sources cannot and will never, no matter how much you want, be able to handle the base load. It has nothing to do with Big Extractive industries. It does not matter what new tech we come up with or how efficient they can make solar panels. They by definition cannot handle our base load. They can never therefore be the answer to our energy problems unless you are willing to cull 85% of the worlds population. The only answer is 100% adoption of nuclear power now, until we can bring in fusion or something better than fusion. Nuclear power means 1000 years of clean safe energy. That is more than enough time for us to solve our energy problems.

Re:Cue the hippies

[Anonymous Coward]

Well, the dirty coal or natural gas used 20 km from your home will be gone in 2 years. The nuke fuel residue will be gone in 2 years also, provided you multiply that by a few thousand, or a few hundred thousand. I understand that nuclear provides a lot of power, and one cannot see the rubbish it makes...but some still think the creation of so much waste is a tad irresponsible for those thousands of years from now. Heck, if you think of how things were in 1812, we'd just now be cleaning up from the nuclear energy used during the war of 1812! (assuming the 200 year cleanup isn't overly optimistic)

Re:Cue the hippies

[lightknight]

Indeed. The political establishment was having trouble getting re-elected, so they merged with whoever they could find to keep themselves in power. Nevermind that it's slowly crippling them.

Re:Cue the hippies

[Anonymous Coward]

"What we lack is not technology, but the ability to kill enough people who depend on energy to live so sustainable energy works for us good folk who are left."

There FTFY

Re:Cue the hippies

[Anonymous Coward]

Good is the enemy of perfection. Don't be a renewables hater by spouting nonsense. We can move all energy production to renewables overnight if it weren't for you pesky kids and your dog.

Re:Cue the hippies

[LWATCDR]

Kind of like the lie that Germany is abandoning nuclear power. Germany is just outsourcing nuclear power too France. All the same risks but without any control over the safety requirements but the Greens believe it so all is good.

Re:Cue the hippies

[mellon]

Yes, thanks for another argument by unsubstantiated assertion. We get a lot of these, and they are always charming. I'm sure you are convinced of the righteousness of your beliefs. However, conservation is quite possible—I live in a house that uses an eighth the energy of a regular house to heat it. So reduction in the base load isn't out of the question. More importantly, though, we are in fact increasing the amount of energy we get from renewables year by year. The only thing slowing us down is that right now, because fracking is so heavily subsidized, the price of a kilowatt-hour generated with natural gas is still lower than the cost of a kilowatt-hour generated with solar. The same is true of nuclear—because it's so heavily subsidized, it's "cheap." Oil actually is pretty cheap, but it's not much cheaper than solar at this point. Take away the massive subsidies on natural gas and nuclear, and the switch to solar, wind, etc will happen fairly quickly.

Re:Cue the hippies

[Anonymous Coward]

Cleaner would be better though. Molten salt reactors work at a much higher level of efficiency (light water reactors are 12% efficient, heavy water reactors are about 14% efficient, molten salt reactors start at 89% efficiency, and and go up to 99% at higher temperatures). Also molten salt reactors are inherently safer because they don't work at high working temperatures and pressures, no no massive, overbuilt containment system needed. It was proposed in 1974, by the Lawrence Livermore Lab in the US (to the US government), because it worked so much better. They threatened the group of scientists with unemployment at least, and the remainder of their lives in solitary confinement at worst. The governments big hangup was that you can't make nuclear bombs with this technology (and so where is the fun in that?). This technology, coupled with that technology, would be the ideal technology (governments won't allow it because they need to support the interests of big oil).

Re:Cue the hippies

[Anonymous Coward]

The fumes emitted by a coal power station emit more radiation that an operating nuclear reactor (not a meltdown obviously). So do living in certain areas if you're on top of granite or one of the many natural nuclear reactors (where pockets of uranium deposits in the earth are already having a sustained nuclear reaction).

Re:Cue the hippies

[KagatoLNX]

I'm quite the proponent of researching molten salt nuclear. It's got some nice properties in terms of failure modes, is inherently anti-proliferation (so I hear), and has some nice options in the way of the thorium fuel cycle (the Chinese seem to have a real interest in this one, unsurprisingly).

Interestingly, molten salt SOLAR is actually quite nice for addressing the chief problem with solar (notably, the whole "sun goes down thing"). See here:

http://news.cnet.com/8301-11128_3-57333789-54/molten-salt-keeps-solar-power-flowing/

Developed in the US not Belgium

[goombah99]

Back in the 1990s this was developed at Los Alamos and a few other accelerator centers. it's not new or unique to belgium.
http://www.lanl.gov/orgs/pa/science21/ATW.html

http://www.world-nuclear.org/sym/1999/venneri.htm

Re:Developed in the US not Belgium

[radtea]

Back in the 1990s this was developed at Los Alamos and a few other accelerator centers. it's not new or unique to belgium.

But because it's a technological solution to a political problem, it's a wheel that will keep being reinvented and everyone who ignored it the previous time will be surprised by it the subsequent time.

The dialog goes like this:

Anti-nukes: "Nuclear power is unsafe. We must ban it!"

Engineer: "Look, I have found a way to make nuclear power safer than coal!"

Anti-nukes: "That would be terrible! It would make people want nuclear power, but we can't be having with that because nuclear power is unsafe. We must ban it!"

Until we have a solution for the political problem, which is that there is a large body of ignorant and fearful people who think that nuclear power is far more dangerous than it actually is and who will steadfastly refuse to ever under any circumstances to compare nuclear power with any other viable source of base-load industrial supply, the advances of technology will be almost completely irrelevant to human progress.

Re:Developed in the US not Belgium

[quax]

What's new and unique to Belgium is that they are embarking on constructing the industrial scale MYRRHA reactor. Don't know of any other accelerator driven reactor project of this scale. TFA contains links to a presentation with the detailed blueprints for this machine.

Re:Developed in the US not Belgium

[AmiMoJo]

Engineer: "Look, I have found a way to make nuclear power safer than coal!"

That isn't what is being proposed. This does not solve most of the problems with nuclear power, it just makes the waste somewhat more manageable.

Even a 200 year half life is way beyond what any commercial company has had to deal with in the past, and realistically it will end up being the government, or more accurately the tax payer, who ends up paying for it.

Re:Developed in the US not Belgium

[delt0r]

There are companies that are older than 200 years you know.

Re:Developed in the US not Belgium

[mcgrew]

Even a 200 year half life is way beyond what any commercial company has had to deal with in the past

Well, in the 1800s railroad locomotives had hundred year warantees, so a thousand year plan isn't that crazy.

Re:It's not "spent"...

[TheSpoom]

Looks like you're pretty spent.

Subcritical fission?

[mlts]

Depending on how big the accelerator has to be, I wonder if this could be used for making smaller reactors, perhaps using thorium instead of uranium as fuel. With the permanent moratorium in place since Carter, this would allow nuclear energy to be useful in the US, and since the reactors are smaller and can be QA-ed at a factory before hitting a site, it means that problems have a greater chance of being caught before the thing goes live.

Subcritical fission isn't just useful for getting rid of fuel, it would allow for reactor arrays to be built when it would be impossible to build the larger type.

Re:Subcritical fission?

[Anonymous Coward]

There are several efforts worldwide aiming at a demonstration of ADSR (accelerator driven subcritical reactors). The US is doing very little.

The accelerator does need to be substantial (think 10MW CW proton beam power at 1 GeV) but there are no insoluble problems here.

Re:Subcritical fission?

[JoeMerchant]

I think it's ironic that the US medical industry is such accelerator experts, but the power industry lags.

Maybe we need mandatory power insurance?

Re:Subcritical fission?

[quax]

TFA links to a science paper of how this design could work with Thorium.

It's the Plutonium...

[Anonymous Coward]

The chief drawback to fuel reprocessing, besides the increased volume of contaminated material, is the concentration of plutonium in the spent fuel. We can't have weapons grade material floating around, now can we?

Re:It's the Plutonium...

[CanHasDIY]

We can't have weapons grade material floating around, now can we?

Something I've always thought a stupid concept, honestly.

Maybe "weapons-grade" fissile materials wouldn't be such an issue, if our species were smart enough to find uses for said materials other than killing each other.

Re:It's the Plutonium...

[ZeroSumHappiness]

We must ban this weapons-grade steel for the good of our children. Bronze is good enough for knives for shaving, tanning hides, working the fields. We don't need steel. The steel industry tries to convince us that steel has peaceful uses but we know that steel weapons easily fall into the hands of bandits and brigands. Arsenic poisoning is simply a lie by big steel so that they can create their death tools. In reality, bronze is safe, reliable and fulfills our tool needs.

Re:It's the Plutonium...

[vlm]

Its really not a big deal because the guys in caves can do it pretty easily if they don't care about dying, or can just use the fuel pellets as is to create contamination.

The chief problem with reprocessing, US, USSR, as far as I know "everywhere" is you're fundamentally going to have to convert a ridiculously chemically inert ceramic or oxide to a water soluble ion, and every freaking place that does it invariably eventually turns into a glow in the dark superfund site.

Can't trust the capitalists, can't trust the commies... Everyone who tries it creates a superfund site, often worst than just dumping the stuff out on the dirt and walking away. Its a law of nature... Making the "stuff" a billion times more bio available by dissolving a ceramic in water means you have to be a billion times more careful not to spill it, or rephrased, being as safe as possible with both the insoluble and soluble stuff means spilling a billionth of the liquefied stuff is now just as bad as dumping the entire solidified batch in the back yard and walking away.

Imagine a big ceramic lump. It'll take a billion years to weather away. Of course in a million it'll totally decay to being as harmless as granite, but... Or you can dissolve it for reprocessing and it seems not to be technologically possible at an industrial scale to not pollute the environment... and unlike the non-reactive lump, the dissolved solution will go right in your drinking water. Ooops.

Also whenever you have "security" it inevitably devolves into "security... provided to coverup the environmental contamination". Combine that with a profit motive and you're got a recipe for disaster.

You need a reprocessing strategy that doesn't involve mechanical grinding or dissolving or ionizing or ... in other words something that doesn't exist. Whoops.

Re:It's the Plutonium...

[CanHasDIY]

We must ban this weapons-grade steel for the good of our children. Bronze is good enough for knives for shaving, tanning hides, working the fields. We don't need steel. The steel industry tries to convince us that steel has peaceful uses but we know that steel weapons easily fall into the hands of bandits and brigands. Arsenic poisoning is simply a lie by big steel so that they can create their death tools. In reality, bronze is safe, reliable and fulfills our tool needs.

Uh-huh, that's exactly what a pro-bronze shill like yourself would want us to think!

Obviously, anything more advanced than rocks tied to sticks is far to dangerous to be allowed to fall into the 'wrong hands,' better go ahead and ban it all...

Re:It's the Plutonium...

[elliotjo]

I've never understood this argument. During the entire cold war, we had an entire industry dedicated to producing nothing BUT weapons grade material. If we could produce it at an industrial scale and maintain security, why does this have to be an all-or-nothing deal? Can't allow reprocessing at the same level of regulation?

Re:It's the Plutonium...

[quax]

While the reprocessing plant Sellafield and La Hague had their issues, none of them have been converted to superfund sites. Maybe the civil EU plants can, where the US and USSR military sites couldn't or wouldn't because it was too easy to sandbag everything under a layer of national interest secrecy?

Re:It's the Plutonium...

[Anonymous Coward]

Bronze is nowhere near sharp enough to shave. Use flint.

Re:It's the Plutonium...

[Anonymous Coward]

Red herring.

Yes, plutonium is created in uranium reactors. No, it is not weapons grade - that is, unless you're using a ridiculously short (and massively uneconomical) 90 day fuel cycle. Inside the reactor, when operating, you get this:

U-238 + Neutron > U-239 > Np-239 > Pu-239
Then, the Pu-239 will grab a neutron and either fission ~70% of the time. The other ~30% it becomes Pu-240 which causes bombs to fizzle if you have too much (more than 7%). You cannot remove the Pu-240 from the Pu-239 with known processes. If it captures another neutron, it becomes Pu-241 for the next ~15 years, after which it becomes Am-241 for a couple hundred years, making up a large component of the highly radioactive waste.

Don't want weapons grade Plutonium? Don't pull your fuel out until it can't be used as fuel in a self-sustaining reaction anymore.

Re:It's the Plutonium...

[delt0r]

Question: Why is there more than 7000000000 people on earth?
Answer: We are not as good at killing each other as our own dogma would have us believe.

Re:It's the Plutonium...

[ZeroSumHappiness]

Brigand! You just want access to deadly, deadly steel!

Re:It's the Plutonium...

[vlm]

While the reprocessing plant Sellafield and La Hague had their issues, none of them have been converted to superfund sites.

Yeah, as far as you know. See below:

Also whenever you have "security" it inevitably devolves into "security... provided to coverup the environmental contamination". Combine that with a profit motive and you're got a recipe for disaster.

If you think basic human nature is magically different in Sellafield and La Hague, we'll send our stuff over for reprocessing... I'm thinking its more wishful thinking...

Re:It's the Plutonium...

[CanHasDIY]

Question: Why is there more than 7000000000 people on earth? Answer: We are not as good at killing each other as our own dogma would have us believe.

Quick GN hangup - that should be "Why are there..." not "Why is there." Ah, I feel better, back on topic:

Disagree; my response: "We're not nearly as occupied with killing each other as we are with breeding."

Re:It's the Plutonium...

[delt0r]

The most effective way of killing each other. Cars. And still not good at it. Old age and complications of that get most of us in the end.

Re:It's the Plutonium...

[quax]

I'll fail to see how nuclear waste reprocessing is any different from other high tech that requires excruciating quality control e.g. like the late space shuttle.

Yes, accidents will happen, but organizational it is entirely possible to enforce proper oversight and ensure that no counter-productive incentives are put in place.

I.e. you simply cannot run a reprocessing plant as a profit center were cost cutting will always trump all other concerns.

NIMBYs and BANANAs

[Chas]

No. Because reprocessing of spent nuclear waste, even into usable nuclear fuel for second-stage deployment has been around for decades.

A bunch of "Nuclear = bomb = baaaaaaaaaad" sheeple will bitch about storage anyhow.
They'll bitch about transportation of the waste in both pre and post-processed forms.

And pretty much ANYTHING else that'd allow companies and government agencies to handle nuclear power (even its shutdown) in a safe, intelligent and responsible manner.

Re:NIMBYs and BANANAs

[bigtrike]

Reprocessing uranium involves producing bomb grade plutonium as a step, so we better regulate the hell out of these plants to make sure they have a small military for protection. The real reason why nobody without massive government subsidies does it is because it's currently cheaper just to get new fuel.

Thorium reactors?

[kheldan]

I keep hearing about thorium reactors. What I've read of it seems to indicate it'd be much safer and cheaper to operate than what we've been using. I really haven't read about any downside to these. Anyone care to fill me in on why we aren't using them?

Re:Thorium reactors?

[Que_Ball]

Primary reason is the many billions of dollars of development needed to figure it all out.

There is no design for a "working commercial thorium reactors". It's all just bits and pieces of theory, and experimental reactors that only answered some of the questions.

It's a possible technology, just not an actual technology. Kind of like the guy at NASA who recently got into the news for a pen and paper proposal of how warp speed might be possible. We are still a long way from building interstellar spaceships. Just like we are long way from building a Thorium salt reactor that works and is economically viable.

Re:Thorium reactors?

[Anonymous Coward]

We haven't used them in the past because they did not produce plutonium for our weapons program. That's not a downside(?) anymore, and thorium looks good on paper, but there's still a lot of development work to be done, and no one is going to put in that kind of investment in the current NUCLEAR=EVIL environment no matter the rational merits. Sad, really.

Re:Thorium reactors?

[Zeromous]

Capitalism and the fact Thorium does not produce products which can be weaponized.

I guess it sort of made sense at the time.

Re:Thorium reactors?

[Anonymous Coward]

Last I read, the dominant issues are the difference between "in theory" and "in practice" as well as the usual anti-nuke whiners. It might actually be the difference between "in lab tests" and "in large scale production" instead, but I think it's one of those typical engineering hurdles.

Re:Thorium reactors?

[sjames]

Uranium reactors were developed first because we (the U.S.) needed bomb grade material. Thorium reactors cannot provide that.

Re:Thorium reactors?

[erice]

I keep hearing about thorium reactors. What I've read of it seems to indicate it'd be much safer and cheaper to operate than what we've been using. I really haven't read about any downside to these. Anyone care to fill me in on why we aren't using them?

1) They are more complex than Uranium reactors we use now. The fuel is cheaper but fuel is not a major contributor to the cost of running a nuclear power plant.
2) They are inherently breeder reactors and that raises concerns about nuclear proliferation. U-232 contamination makes it actually rather difficult to use a Thorium reactor to make bomb material but not everyone is satisfied that is it difficult enough.
3) U-232 contamination also makes normal operation more difficult too. U-232 is an intense gamma emitter. All handling must be done remotely.
4) Politics has made it difficult to get even modernized non-breeder reactors built, much less anything as radical like thorium.

Re:Thorium reactors?

[denis-The-menace]

You could watch "LFTR remix 2011" but since google/YouTube is down where you live:

-Banks don't like unknowns. A commercial-grade LFTR reactor has never been built. If it did they would know how long it would take for the reactor to make $.
-Current regulations only cover WW2-tech reactors. Anything else is a gray zone. So, no permits, etc.
-Current nuclear industry is a monopolistic cash-cow. They don't want to end the 25-year, sole source supply contracts for solid fuel.(You can't buy fuel pellets on special on E-bay or Walmart...)
-Governments want to please the NIMBYs and nuclear-phobes. They would rather live with the time-bomb reactors we have in service today.
-LFTR could kill the coal and the oil well business. so...

(BTW: Coal power plant makes radio active ashes)

Re:Thorium reactors?

[werfu]

Thorium reactor designs are somewhat "new" or unproven compared to actual nuclear reactor. The nuclear reactors operators are somewhat conservative, but it's quite understandable. You don't want something going wrong when you mess with radioactivity. But we should see Molten-salt thorium reactor in a somewhat near future, India having bought the right to build them.

Re:Thorium reactors?

[vlm]

They are inherently breeder reactors and that raises concerns about nuclear proliferation. U-232 contamination makes it actually rather difficult to use a Thorium reactor to make bomb material

Close but wrong. All you need to make Pu is some U (no big deal) and some excess neutrons laying around for the U to soak up... like from a Th reactor.

A Th reactor can cook above delayed critical (obviously, otherwise how does it power up?, think about it). So you have a convenient controllable source of excess of neutrons laying around, and its no great technical achievement to shove a U target in there to soak up the excess neutrons thus making yummy Pu.

You have a really awkward situation of trying to prove they're not operating sloppily given the burnup vs claimed power output ratio. Its like using a town's Census and GDP figures to prove there's a meth cook in the town based on monetary flow rates or something... its just not gonna happen.

Or you can play around with making a design thats barely critical when you crank out all the stops, which is going to be an unholy PITA to operate and probably not terribly stable.

Hilariously, if you build a dual purpose reactor made to generate power and have a facility for neutron activation (research, hospital radiation therapy, etc) then all you need to do is stick a chunk of U in the neutron activation pig (usually pneumatic like a bank drive thru window) and pop that dude in the reactor and you'll get SOME Pu. Now you'll need more than a research pig to make a big Pu powered boom anytime this century, but this can be scaled up and this gives you an idea whats up.

It'll be slow and non-productive, but some big booms are worth waiting for.

Re:Thorium reactors?

[Anonymous Coward]

That is not an apt comparison (with a theoretical warp drive) as molten salt reactor technology has already been demonstrated, the concept is sound, and the main barrier to their development and deployment is a lack of interest. The thorium community is currently busy trying to advocate their use as many of us believe that the technology has the potential to dramatically lower the cost of energy by turning nuclear power into something universally desirable. These machines have the potential to be flexible, scalable, very clean, and super efficient. We could run our entire economy on these things, and if the low cost of production is demonstrated, we will be able to essentially eliminate poverty. Definitely a powerful idea worth pursuing.

Re:Thorium reactors?

[cheesecake23]

Very good summary of the arguments against Thorium, but your first point can be put more succinctly:

1) They are more complex than Uranium reactors we use now. The fuel is cheaper but fuel is not a major contributor to the cost of running a nuclear power plant.

1) There is no economic advantage to Thorium reactors.

And make no mistake: the main factor holding back nuclear all over the developed world is not safety issues, public opinion, waste management or proliferation, but cost.

Re:Thorium reactors?

[Anonymous Coward]

That might explain why there are no such reactors in the US, but there are plenty of other countries interested in nuclear power. India is actively seeking thorium based solutions due to having large thorium deposits within their country, but still have a ways to go and will have to see how effective it is. There is still engineering to be done, it is not just regulations and lack of interest holding it back.

Re:Thorium reactors?

[quax]

If you read the TFA it links to a paper that discusses Thorium use in an accelerator driven reactor. I guess in a sense this is a breeder but the Thorium fuel cycle only requires Plutonium to achieve criticality. Don't see a need for it in this kind of sub-critical design.

Plutonium management really is a matter of political will, one can also argue that Thorium can be used to constrain Plutonium as this paper does (PDF).

Re:Thorium reactors?

[Anonymous Coward]

BS. The only part you've got right is billions of dollars which is what the companies heavily invested in the current nuclear arrangement would lose. It's not all that hard to figure out. Experimental reactors exist and work just fine. Fuel is in abundance. It's fail safe (won't melt down). And as an added bonus the waste has a shorter half life.

Re:Thorium reactors?

[Anonymous Coward]

Oak Ridge spent a decade doing research with thorium reactors, and they are being built by other countries. Advantages:
* Order-of-magnitude less radioactive waste.
* Cannot build a bomb from the waste.
* Half-life is very short.
* Relatively abundant, domestically.
* Occurs with rare-earth metals, so both can be produced.
* Current reactors can be modified to use it.
Disadvantages:
* Extracting thorium has been an environmentally difficult problem, so no current domestic production.
* No bomb-making option prevented it from being exploited post-WW2.
* Hence the entire uranium supply chain is in place, no such thing for thorium.

Re:Thorium reactors?

[lightknight]

Hmm. Capitalism kind of operates on the idea of profitability, so if you can make an argument that a Thorium reactor will be profitable (even a 10% return on investment), people will listen. If you can argue that it's more profitable that a Uranium-based reactor, even more people will listen.

No one, in their right mind, slights someone who will arguably make them a little richer at the end of the day. None of us are wealthy enough that that isn't a problem.

Re:Thorium reactors?

[CodeMunch]

The U232 makes it deadly to handle therefore extremely difficult and unlikely to use for machining into something usable as a weapon. I'd never say someone couldn't but there are likely easier ways of getting U. Anyway, If you have a LFTR reactor, you already have a bunch of U in the core. The U232 is bred in the blanket later of a LFTR reactor, filtered out through fluorination and pumped back into the core for fuel.

A Th reactor can cook above delayed critical (obviously, otherwise how does it power up?

A LFTR starts with a core of U (I believe it is U235) in the Berylium Fluoride - That is what powers it. The Thorium (in the blanket layer) is only there to breed more U (U232), slow neutrons, carry away heat. LFTR's are still reactors powered by U, the cool thing is 1. breeding more U, 2. operates at atmospheric pressures, 3. uses Berylium Fluoride for cooling & heat transfer and therefore does not need water, 4. They don't need massive containment vessels for steam so they are also much smaller. No water means no pressure build up (steam) and no hydrogen being split from H2O (big boom & fire).

Somewhere in the decay chain, Pu can/is created but in very minute quantities, not enough for weaponization and I believe it gets consumed as well in the long run. I haven't read up on LFTR for a while so I forget where the Pu goes. I read/saw somewhere the amount that was generated and my feeble memory wants to believe it was a few milligrams per year in an ocean of molten Beryllium Fluoride.

Re:Thorium reactors?

[kheldan]

-LFTR could kill the coal and the oil well business. so...

Wah.
Coal and oil aren't going to last forever, or much longer for that matter. Wouldn't it be nice, for once, if humans would actually change something before it became a life-or-death situation?

Re:Thorium reactors?

[Anonymous Coward]

10% return on investment as compared to what? The real issues are opportunity cost and risk. Those two factors are big unknowns when it comes to thorium. Using existing designs means your opportunity cost and risk (financial and regulatory) are very well understood. Add several well known cognitive biases, and moving to thorium requires jumping several major hurdles---perhaps insurmountable.

Path dependence is one of the most significant determinants in all industries, including the finance industry.

Re:Thorium reactors?

[HalfFlat]

There is no design for a "working commercial thorium reactors". It's all just bits and pieces of theory, and experimental reactors that only answered some of the questions.

This is not true — CANDU reactors can burn thorium in a number of fuel configurations, and they have been around for decades. That none are operating commercially on a thorium fuel cycle is, I believe, primarily due to a combination of regulation and infrastructure considerations.

Next generation thorium reactors will be great, but we already have the technology to use thorium. We just don't.

Re:Thorium reactors?

[Anonymous Coward]

It is amazing how facts contradict so many statements here.
Your statement is like saying that NASA is not flying man because they never have and it would cost 100s of billions of development needed to figure it all out.

USA has been doing Thorium back in the 60's, 70's, and into the 80's. And the above was just ONE plant. There were others, though IIRC, none as large.

Re:Thorium reactors?

[triffid_98]

The United States has enough proven reserves of coal to last for several hundred years at our current rate of consumption. Even then we don't really run out, it just gets progressively more expensive to extract.

Given that gasoline can be made out of coal, even if the middle east went dry tomorrow we wouldn't really be out of oil, we'd just be out of cheap oil...

Re:Thorium reactors?

[Anonymous Coward]

Capitalism actually developed it back in the 60-80s. And interestingly, it is VERY economically viable today. More importantly, USA and the rest of the west, needs to restart this.

Re:Thorium reactors?

[erice]

If you read the TFA it links to a paper that discusses Thorium use in an accelerator driven reactor. I guess in a sense this is a breeder but the Thorium fuel cycle only requires Plutonium to achieve criticality. Don't see a need for it in this kind of sub-critical design.

The conventional Thorium fuel cycle does not require plutonium at all. It just requires some fissile material to start the process. Enriched uranium is the conventional choice.

However, any Thorium reactor is a breeder. Fissile Uranium-230 is bred from non-fissile thorium and Uranium-230 is just as good of a bomb material as plutonium. That is, if you can can remove the U-232, which is a bit of a trick.

Using the particle accelerator removes the need for an enriched U-235 to start the reactor. That is useful since it could eliminate the need for any Uranium enrichment for the purpose of power generation.

Re:Thorium reactors?

[quax]

CANDU is another example for a reactor design that while not sub-critical is much safer than most other designs due to its ability to use natural uranium. The latter obviously does not have a tendency to spontaneously sustain a fission reaction. (Although in nature this apparently occurred at least once in earths history in Africa).

Re:Thorium reactors?

[quax]

Thanks for the correction with regards to the plutonium. Indeed any fissile material will do.

Re:Thorium reactors?

[gullevek]

Part is right, that there is a lot of research to be done. But not because we never built one, but more because we forgot how to built one. The US had one running for quite some time.

Re:Thorium reactors?

[Anonymous Coward]

Sure, but that's largely true of any reactor that produces excess neutrons, including uranium fuelled ones. However, if you're running a thorium reactor, why would you have uranium around in the first place? It's much harder to make plutonium surreptitiously when the raw materials aren't the same as your reactor fuel.

Re:Thorium reactors?

[rufty_tufty]

That and these reactors need molten sodium.
You know that stuff that if it touches air it combusts, or if it contacts water it combusts. Oh and it's at about 400 degrees. And highly corrosive(so very very hard to completely contain and pump). Then you're making it radioactive. A better definition of liquid death would be hard to come up with. (actually the thought occurs that for space based reactors most of these problems go away. Hummm.....)
That said I'm all for the use of this technology but it's disingenuous to imply that it is either a solved problem or easy. Especially when there are easier and cheaper solutions available. When the cost of fuel becomes significant then it's much more interesting.

Re:Thorium reactors?

[AmiMoJo]

That none are operating commercially on a thorium fuel cycle is, I believe, primarily due to a combination of regulation and infrastructure considerations.

That is what the GP said. It would cost billions to get them certified and to develop the infrastructure and procedures necessary to run thorium fuel. Thorium also makes decommissioning much harder, which will also cost billions to address.

It doesn't make economic sense to do it, that is why no-one does. The nuclear industry is really screwed up, dependent on subsidy and due to high up-front costs only able to keep selling the same old tech to the investors who will front the money. Renewables are also now drawing a lot of that investment away because that is a fast growing sector with much shorter term returns and lower risk.

Re:Thorium reactors?

[Zeromous]

Right, so ergo, it is not profitable to maintain two lines of nuclear reactors, two R&D channels- one for civilian power and one for weapon grade uranium if you can kill two birds with one stone....Your answer to this riddle is Uranium fission, rather than Thorium.

Re:Thorium reactors?

[delt0r]

The facts are not nearly as good as the current group think on /. would have you believe.

First the basics. Th is not a fuel but is fertile. That is you can turn it into fuel with neutrons, which you can get from your final fuel. Chicken egg issues are solved with a 235U or Pt starter. 232Th is transmutation into 233Pa which is a neutron poison. The breading ratio is already marginal so you need to constantly remove this for any hope of a useful breading ratio (ie you make at least as much fuel as you burn). The 233Pa decays into 233U. That is right the fuel is still Uranium. Its a lighter isotope and tends to fission better and produce less actinides. Actinides are things higher up the periodic table than Uranium and are the hard stuff to deal with in nuclear waste. Less is not none. But then you don't have any 238U sitting around producing Actinides either. So that is good.

So lets start with some basics issues. We have to get the 233Pa out continuously... We are still burning Uranium and as such the fission product waste is the same, the decay heat(ie shut down is not the same as won't melt down) is the same, the radioactivity of the core is the same. So we still have about the same waste as any other Uranium reactor with reprocessing and we have the same core breach/meltdown issues as any other reactor. Proponents compare it too a once though Uranium cycle and claim 50x less waste or whatever. Lets be clear, once through fuel cycles are braindead.

So why the claims of "solves all issues with nuclear energy"? It is how the first issue was solved. One way to get the 233Pa out continuously before it becomes 234Pa is to use liquid fluoride salt. In fact any salt will do but fluoride has only one isotope and some favorable chemistry and physical properties. It should be noted we are dissolving 233U in this salt and as such 238U and 235U is equally soluble. Now the fuel is part of the primary coolant. This is one example of a larger class of homogenous reactors and have many nice properties regarding control and off design point behavior, even burn etc. None of these advantages have anything to do with Th. Basically burning actinides in this class of reactor is fairly easy compared to where the fuel is solid. That is we can burn plain old 235U/238U in a fast configuration with all the same waste advantages and safety advantages as proponents claim for Th.

But this is not the whole story. No matter what you do you always get a little 234U (from 234Pa and 233U that does not fission). This is a hard gamma emitter and its claimed because glove in box type procedures cannot be used this makes building bombs much harder. This is true. But we *must* handle this to reprocess. If you can handle these hard gammas for reprocessing you can handle them for bombs. In fact they did. 233U bread from Th was used at least partially for one (even 2) bomb tests. Also you can always just put 238U around the reactor to get plain old 239Pt for the old fashion type bomb. Any reactor is always something of a proliferation risk. Also how much extra will dealing with these gammas cost?

Finally lets consider some real world experience. It was claimed that pebble bed reactors where passively safe and nothing could go wrong. Well the prototype in Germany was a total disaster. Between leaks of radioactive material, blocked pipes and all sorts of issues with the fuel elements. Now its a decommissioning nightmare. So much for safe. This is the same. Just because you claim something can't happen, does not mean it can't. Next consider that there has never been a breading Th reactor. A breading ratio of 1 has not been demonstrated.

TL;DR: Most advantages are because its a molten salt reactor with in situ reprocessing. Most of these advantages applies to Uranium fuel cycles as well. Waste stream is the same as Uranium used in similar reactors. Its still a nuke plant. With no real instant shutdown (decay heat) and all the same issues with a core breach or melt down as any other nuclear plant. They are not a silver bullet.

Re:Thorium reactors?

[delt0r]

You can't really get a breading ratio of 1 without continuously reprocessing all the fuel with Th. The 233Pa is a neutron poison. Current reactors use Th to supplement, not replace normal uranium cycles.

Re:Thorium reactors?

[delt0r]

* Order-of-magnitude less radioactive waste.

Only if compared a reprocessing cycle (Th) with a once thorough cycle. Once you reprocess both. Waste streams are very similar.

* Cannot build a bomb from the waste.

You can. It is harder but can be done. It was done.

* Half-life is very short.

Fission produces are the same as for 235U and similar to 239Pt and hence have the same half life. Since you are burning 233U this is not surprising. You only save on actinides compared to Uranium which are dealt with in a proper reprocessing cycle anyway.

* Relatively abundant, domestically.
* Occurs with rare-earth metals, so both can be produced.

In fact there is about 5x more Th land reserves than U.

* Current reactors can be modified to use it.

No they can't. You can't really get a breading ratio of one without pulling out the 233Pa intermediary. Th is currently supplementing, not replacing, uranium. Th breading ratio of 1 or more has not been shown. Simulations for special designs are even marginal.

Re:It's not "spent"...

[Anonymous Coward]

I subconsciously make this typo all the time.. I know it's wrong and usually catch it with proofreading - it comes from common finger-typing-patterns.

That's the long term plan for the industry

[Que_Ball]

Yes. Spent fuel has always been considered a long term asset by the nuclear industry. People in that industry believe that as mining the raw ore becomes more expensive and the technology for reprocessing the spent fuel becomes better it starts to become a more valuable source of future fuel.

The industry would be very different if the governments did not push the technology towards weapons production. The reactor designs we have are all old and they are designed in a way that facilitates the production of plutonium. If the research into other reactor and fuel designs that did not have as many dangerous byproducts were pursued it would be a safer industry today.

The most promising alternative is and was to use Thorium fuelled reactors instead of uranium. There is the potential for far safer reactor designs and far less hazardous waste when using that type of fuel. The USA took a relatively short look at this but then they stopped since they could not also produce weapons from these reactors and at the time it was all about the bomb. But from what I have read they will likely become a technology that becomes more interesting over time as it's capable of using depleted uranium along with the Thorium as a way to use up that spent fuel that's hanging around.

It should be obvious though there are significant challenges to getting the theory into a practical design. All those research reactor projects back in the 50's that gave engineers and scientists the knowledge to build the current reactors would need similar efforts to develop the technology for these alternative fuels and reprocessing technologies. It's starting to happen but in China and India where they have not lost their love for nuclear power yet.

Re:That's the long term plan for the industry

[kevkingofthesea]

The USA took a relatively short look at this but then they stopped since they could not also produce weapons from these reactors and at the time it was all about the bomb.

Alvin Weinberg (former head of the Oak Ridge National Lab) actually took on a fairly ridiculous nuclear aircraft project in order to be able to put more development time into LFTRs.

Re:That's the long term plan for the industry

[vlm]

starts to become a more valuable source of future fuel.

To expand on that, non-nuke people think fuel is burned up and there's just a tiny percentage of ash remaining, like coal plants.

Nukes work differently. Usually the fuel rods have to support themselves... what fraction of atoms in a chunk of "stuff" can you screw up and its still recognizably a chunk of "stuff"? AKA "burnup" or "burnup ratio". Well it turns out "a percent or so" is the most you can do before mechanical properties get all weird. More with some chemistries and designs, less with others.

Imagine as a thought experiment a "coal plant" where the coal is formed into pencil like rods, and the rods are burned until it would be too risky WRT collapse. Maybe you could only burn one percent of the coal. The other 99% is perfectly ready to use coal, plus 1% of really icky waste contaminants that have to be removed. Thats kinda how nukes are.

By weight, almost all of the "waste" is perfectly good unburned fuel.

Re:That's the long term plan for the industry

[Anonymous Coward]

By weight, almost all of the "waste" is perfectly good unburned fuel, that would kill you if you ingested it or just got too exposed to it.

There, fixed that for you.

Re:That's the long term plan for the industry

[mug funky]

not even slightly true.

nuclear regulation became ridiculous precisely because of non proliferation.

the weapons focused designs are almost all but decommissioned (one of them decommissioned itself spectacularly in 1986...). the UK still has a few running. their distinguishing feature is the ability to hot-swap fuel while keeping it running. you can't do that with a PWR or BWR - you fuel it all in one go, you leave it a couple of years (viable pu239 production takes a couple of weeks, not years. if you let it cook too long it all ends up being pu240 which is not at all useful for weapons, as the north koreans could tell you).

please do a little reading on the subject. i'm a little tired of the "todays reactors are shit because they were made to make weapons". it is in fact the opposite of the truth - they were made to make weapons impossible to all but military reactors.

Re:That's the long term plan for the industry

[mug funky]

(granted, the fuel cycle infrastructure can certainly be used to enrich uranium beyond the small amount needed for commercial reactors).

Re:That's the long term plan for the industry

[Anonymous Coward]

Yes, it WOULD do that. Therefore, the smart thing is to burn it up in a 100% safe reactor like a molten salt reactor. THEN, we will have little of that wicked stuff around. More importantly, we would only need to store about 5% of the current waste and it would be moderately safe in less than 200 years.

Re:That's the long term plan for the industry

[MtViewGuy]

Actually, the liquid fluoride thorium reactor (LFTR) could actually make a huge contribution to getting rid of nuclear waste.

Why? Because spent uranium reactor fuel rods and even plutonium from dismantled nuclear weapons could be reprocessed into a form that could be used in an LFTR by dissolving the reprocessed nuclear material in molten sodium fluoride salts. And after this fuel is used up, the final radioactive waste is very small in amount and only has a half-life of under 300 years, which means very cheap disposal costs (you don't need Yucca Mountain anymore--all you need is a disused salt mine or salt dome).

Small wonder why Alvin Weinberg's research is being dusted off and both China and India are seriously looking at developing LFTR's that could generate as much as 1,000 MW per reactor.

Re:That's the long term plan for the industry

[lars_stefan_axelsson]

not even slightly true. nuclear regulation became ridiculous precisely because of non proliferation.

Since we're talking Thorium I would beg to differ. The whole reason we're burning Uranium on a massive scale in the first place is to get Pu that could then be turned into weapons. That's why U/Pu reactors, physical, nuclear, chemical properties etc. were researched and the infrastructure was developed. When we later decided to go all "civilian" then it was too late. The infrastructure/industry was already weaponized.

Now Thorium OTOH was never given the chance just *because* it can't be weaponized, and hence, with only civilian applications, was not even kept on the back burner. Now it suffers a substantial drawback as we would need large industry wide changes (including sending the nuclear engineers back to school) to make it viable. Changing over to molten salt Thorium is not an easy task. And that's even without considering that not all the technical issues are solved yet (molten salt tends to be somewhat corrosive...)

And it's all because of the worlds insatiable thirst for the bomb.

Re:That's the long term plan for the industry

[Anonymous Coward]

I spent the summer in a place called 'Lianyungang' in China. Apparently, has the 'world's safest' nuclear power plant (Russian design, Tianwan Nuclear Power Plant).

https://en.wikipedia.org/wiki/Tianwan_Nuclear_Power_Plant

Re:That's the long term plan for the industry

[Anonymous Coward]

The USA took a relatively short look at this but then they stopped since they could not also produce weapons from these reactors and at the time it was all about the bomb

Except that waste from commercial power plants is not suitable for weapons manufacture, because the fuel stays in the reactor vessel long enough to poison the Pu-239 with Pu-240 and Pu-241. There's a reason why the Department of Energy operated the reactors at Hanford - They were designed and operated to create Pu-239 in quantity and purity.

Posting anon to preserve moderation.

Re:That's the long term plan for the industry

[MachineShedFred]

By weight, almost all of the "waste" is perfectly good unburned fuel, that would kill you if you ingested it or just got too exposed to it. Therefore we should load it back into the reactor vessel designed to contain such a hazardous material and dispose of it by way of electrical generation.

There, fixed that for you.

There's no such thing as nuclear waste...

[Gordonjcp]

... there's just stuff you haven't configured your second fast-breeder reactor to run on yet.

Re:There's no such thing as nuclear waste...

[Hillgiant]

Yeah, sure until you have stripped everything down as far as will go and are left with a cloud of hydrogen gas... oh. I see. Clever.

Re:There's no such thing as nuclear waste...

[Gordonjcp]

Yeah, you get that hydrogen and fuse it into helium, thus preventing us running out of helium like we're always hearing about.

Re:There's no such thing as nuclear waste...

[Anonymous Coward]

Exactly!

Could this lead to a revival of the nuclear industry and the reprocessing of spent reactor fuel?"

No, reprocessing has *nothing* to do with waste. It has everything to do with fuel costs. If Uranium costs more than $120 or $150/lb, you bet we would be running reprocessing plants. Until then, it is cheaper to mine new uranium and let the "waste" sit around for higher prices.

As for accelerators used to transmute waste to short lived ones, well, I can't believe that would be an efficient way removing waste problem. Fast neutron breeder reactors would remove most of the so called waste anyway.

The cheapest is just to store the waste and wait. It is not going anywhere. It is solid material. All you need is more than 1 inept guard watching an entrance to the storage area (you know, watching for things like unauthorized semis and such).

Re:There's no such thing as nuclear waste...

[quax]

Good luck trying to get another fast breeder approved in Europe.

On the other hand the inherently safe sub-critical design gets the go-ahead.

Makes perfect sense form my point of view. I wouldn't want to live near a fast breeder.

Re:There's no such thing as nuclear waste...

[Neil Boekend]

It'd be iron, which we probably need to build our Dyson sphere anyway.

Re:1,000 year? 200 year? Who cares.

[Anonymous Coward]

You're missing a very important point. Many governments (specifically the US) pay HUGE amounts of money for OTHER people to take the waste. So not only would you not spend a cent creating new energy... but you'd be paid for it.

But fusion?

[Anonymous Coward]

We'll we'll all have energy too cheap to meter when fusion is developed.
In 20 years or so...

Resonates with me, for some reason

[Anonymous Coward]

"I never thought I'd see a resonance cascade, let alone create one. "

How much?

[Anonymous Coward]

I thought the problem was that trying to scale the technology was very difficult. On facility said that they could transmute long lived radioactive isotopes into short lived only in small quantities. I think they transmuted something like 30g of material in 3 weeks!

If they can't scale this up.. BIGTIME.. then there's no way this will ever be useful. At the rate the waste is generated it will decay naturally before it could all be transmuted.

Yes, I work in the nuclear industry. When I read about this technology a year or so ago I was cautiously optimistic.

Re:How much?

[quax]

The news value of TFA is really in the fact that the planned MYRRHA project is supposed to be industrial scale.

sounds too good to be true

[edxwelch]

The "transmutation" of nuclear waste into harmless substances, sounds too good to be true? That's because it is. This paper takes a more critical look at the theory: www.laka.org/docu/boeken/pdf/6-01-5-56-25.pdf

"Transmutation of all long-lived radionuclides into short lived ones to a degree sufficient to obviate the need for a geologic repository is practically impossible. In particular, the transmutation of separated uranium, which constitutes about 94 percent of the weight of light water reactor spent fuel and which is very long-lived and generally
contaminated with some fission products, would be counterproductive. The main transmutation route for almost all the uranium would be to convert uranium-238 (the dominant isotope) into plutonium-239. Hence, the complete transmutation of uranium-238 essentially requires the creation of a plutonium economy, which would be unsound
whether viewed from an economic, environmental, or non-proliferation standpoint. Almost all the uranium must therefore be disposed of without transmutation as a matter of practical necessity. Other long-lived fission products as well as residual transuranic actinides would also need disposal. Hence, a repository, as well as other waste
management and storage facilities would still be an essential part of transmutation schemes. "

Re:sounds too good to be true

[thrich81]

If they (the referenced paper, which I flipped through) are saying that you need to transmute the U-238 to a short-lived isotope to make it safe, they are nuts. U-238 has a half-life of 4.5 billion years and so is not very radioactive, it is what primarily comes out of the ground. If the industry were to just mine the natural uranium, take out the U-235 for reactors then put the leftover U-238 back into the ground (or dump it in the sea which already has a lot of natural uranium) then the final result is less natural radioactivity than what was started with. Considering U-238 as a dangerous waste product weakens their argument considerably.

Re:sounds too good to be true

[Anonymous Coward]

Yes, U-238 gets turned into Np-239 and then Pu-239 or Pu-240. One of the major difficulties people have transmuting U-238 into Pu-239 is that they need short irradiation times and lots of reprocessing to keep the Np-239 from picking up that extra neutron. A decent part of the energy from current reactors comes from transmuting and burning U-238. There's a lot of plutonium in the waste, which is too contaminated with Pu-240 for weapons use.

The whole point of this exercise was to burn the Pu-239 and Pu-240.

Stupid leftists hate radiation even more than they hate racism. I used to be a anti-nuclear leftist myself. Then I decided to study some physics.

Re:sounds too good to be true

[quax]

As another commenter pointed out transmuting U238 is kind of pointless. The Minor Actinides is specifically what they are after (this becomes clear if you look at the linked papers and presentation in TFA).

Re:sounds too good to be true

[Prune]

Shame on you for posting a "paper" that is published by a politically driven organization (IEER) and not any recognized academic journal.

Re:sounds too good to be true

[Anonymous Coward]

Mod parent down! He's trying to pass off an article by a major personality in the anti-nuclear movement as a scientific paper. The IEER for which this 'research' was written even has the anti-nuclear logo on its freakin wikipedia page, for fuck's sake!

Re:sounds too good to be true

[quax]

Because your stance is so obviously non-political?

Re:sounds too good to be true

[quax]

Ups, accidentally replied to the wrong comment. Please disregard the previous reply.

Re:sounds too good to be true

[Anonymous Coward]

Transmutation of all long-lived radionuclides into short lived ones to a degree sufficient to obviate the need for a geologic repository is practically impossible.

True, but they're reducing the storage time to 200 years which is significantly better than the status quo.

In particular, the transmutation of separated uranium, which constitutes about 94 percent of the weight of light water reactor spent fuel and which is very long-lived and generally contaminated with some fission products, would be counterproductive. The main transmutation route for almost all the uranium would be to convert uranium-238 (the dominant isotope) into plutonium-239. Hence, the complete transmutation of uranium-238 essentially requires the creation of a plutonium economy, which would be unsound whether viewed from an economic, environmental, or non-proliferation standpoint. Almost all the uranium must therefore be disposed of without transmutation as a matter of practical necessity.

No different from letting it transmute normally over a longer time period.

Re:sounds too good to be true

[ceoyoyo]

Even the quote you cherry picked sounds like it was written by someone with a bachelor of arts more used to getting drunk and arguing about whether Tolstoy could beat Chekhov in a fight.

you are missing the point

[Anonymous Coward]

what a laugh - only 200 years

200 years ago the wealthy were burning candles for light.
200 years ago horses were the fastest means of transport
200 years ago cobblestone pavement was state of the art infrastructure
200 years ago soldiers lined up opposing each other and fired flintlocks

who knows what state we will be in 200 years from now. better or worse.

Re:1,000 year? 200 year? Who cares.

[HornWumpus]

No they don't. They _collect_ HUGE amounts of money to be used to find/build a permanent storage facility.

They spend the money on bread and circuses while leaving the waste at the plants. Typical federal government.

Re:1,000 year? 200 year? Who cares.

[Anonymous Coward]

The US government pays for reprocessing since Carter banned it here in the US. The US is not alone. There is a large reprocessing industry.

But please, don't let something like facts get in the way of your rant.

How long for a thousand tons?

[Anonymous Coward]

Gee....I wonder how long it would take to convert a thousand tons of waste? And it makes it decay in only two hundred years. So I guess we just put in a landfill in two hundred years. What could possibly go wrong?

Are accelerators power efficient?

[erice]

Ive always heard of particle accelerators as enormous power hogs. Is this really an effective means of generating net power? If neutrons can be generated efficiently, couldn't you also use this to generate power by directly fissioning U-238? (I.e., not breading plutonium)

Re:Are accelerators power efficient?

[Anonymous Coward]

Breeding (not breading like fried chicken!) plutonium is really much more power efficient -- you might get a lot of energy continuously fissioning U238, but a plutonium warhead will deliver far more power.

Re:Are accelerators power efficient?

[Anonymous Coward]

Well, U-238, like Th-232, isn't fissile. U-238 absorbs a neutron to make Pu-239, and Th-232 absorbs one to make U-233. These are the fissile isotopes. Yes, you can use U-238 in the same way as Thorium, in ADSR or a breeder reactor, but there are two disadvantages: Thorium is more abundant and easier to mine than Uranium, and it doesn't produce Pu-239, so doesn't make it so easy to produce things that go boom.

In terms of the efficiency, you need a few MW of proton beam power at around 1GeV to drive a 2GW Thorium ADSR. That few MW of proton beam costs you tens of MW of electric power.

Re:Are accelerators power efficient?

[delt0r]

Not quite. 238U is fissile with fast neutrons. This was the reason castle bravo had a much higher than expected yield when the 238U tamper was fissioned by the fast fusion neutrons. In a fast reactor 238U fission is a significant contribution to the total power output.

Anyone seen the...

[Anachragnome]

Anyone seen the Firehose lately?

It appears to have been removed.

Anyone?

Re:Anyone seen the...

[Anonymous Coward]

http://slashdot.org/recent

Obligatory XKCD

[TuringTest]

Think Logically

The great thing is, this XKCD strip is relevant to all Slashdot inflammatory threads!

Re:It's not "spent"...

[Anonymous Coward]

I know it's wrong and usually catch it with proofreading

Proofreading, what's that? It's not something I've ever seen at /. before.

Still not enough

[slazzy]

While I think this would be great to deal with the waste that already exists, I think for budgeting 200 years is longer than anyone is willing to think anyways, so it won't make much of a difference to the financial viability.

Re:Still not enough

[Anonymous Coward]

We already have technology to deal with nuclear waste. This is a wheel reinvented. Here's how we can deal with it today, if the politicians get out of the way:

1. Load new fuel into light water reactor
2. Run it until the neutron poisons build up, which prevent criticality
3. Unload "spent" fuel from reactor
4. Subtract the 1% of the fuel assembly that absorbs neutrons and prevents criticality with chemical separation
5. Send the 99% of the fuel assembly back to the reactor
6. Take out the useful fission daughter products from the 1% (nuclear medicine, industrial, etc.)
7. Store remaining 1% in Yucca Mountain for a period of a couple hundred years, rather than 100% of fuel assemblies for tens of thousands of years.

We know how to do this today. We even have the facilities and equipment, remaining from bomb production during the Cold War. We just don't do it. Instead, we talk about it. And talk. And then talk some more.

Posting anon to preserve moderation.

How big a plant?

[Animats]

This has been talked up for a decade or two, but needs cost and capacity numbers.

There's also the painful fact that every reactor design that had anything mechanically non-trivial inside the reactor has been a flop. There have been two German pebble-bed reactors, both of which had pebble jams serious enough to cause major accidents with significant radiation leaks. Tsinghua University in China has one that's worked for a while, and that design is being scaled up. The Rongcheng Shidaowan Nuclear Power Plant, with two pebble-bed reactors, is under construction now. Completion in 2015. Maybe they can make it work. We won't really know until there are a few hundred reactor-years on that technology.

High temperature, gas-cooled reactors have been tried, but were troublesome. The only big one was Fort. St. Vrain, which had a lot of troubles with auxiliary equipment and corrosion. It only ran 10 years. No big safety issues, though; just high maintenance costs.

Re:How big a plant?

[quax]

An accelerator beam I would not consider a mechanical system. No moving parts.

At any rate these research reactors are build to determine technological feasibility, are they not?

If you're building an accelerator ...

[Crypto Cavedweller]

Build a linear accelerator and launch the waste at the sun.

Re:If you're building an accelerator ...

[dlingman]

Isn't the moon a lot closer? We could put it on the far side to not even mess up the moonscape we can see...

Maybe the wrong problem

[Anonymous Coward]

Their stated advantage is that when you turn off the Neutron beam, the reactor stops reacting.

In a regular reactor, the control rods stops the primary reaction, but it takes about 24 hours before the thing can be left without active cooling.
    (Which combined with a dead cooling system due to flooded backup generators is what killed the reactor in Japan.)

We need a reactor that can be switched off and passively walked away from.
      (Also, not having storage pools outside containment would be nice as well.;-)

Are they saying this process is fundamentally safer in this way, or that it's just a better control rod.
    Perhaps with this system, there is no need for enough fuel to form a critical mass no matter what the geometry?

(That would be good.)

Re:Maybe the wrong problem

[quax]

My understanding is that this would be designed with passive cooling.

Re:It's not "spent"...

[Will.Woodhull]

I wish I had mod points.

Well done, Sir!

Speaking as a (ex) physicist...

[Anonymous Coward]

The main problem up to now has been a problem of quantity done versus price. It is actually pretty damn cheap to put stuff in salt mine for a long time. Furthermore it is compounded by the fact very long term element (half life above 1000 years) are poorly radioactive and those below a few year half life are rapidely not a problem. And the final nail is that a lot of what is put in waste salt mine are actually useful and could be reused, but due to many concern on proliferation and dirty bombs, simply put in guarded salt mine.

Re:1,000 year? 200 year? Who cares.

[icebike]

They spend the money on bread and circuses while leaving the waste at the plants. Typical federal government.

Actually leaving the waste at the plant may in the long run prove to be the right decision.

After all, if this method works it is likely to be co-located with an existing generation plant, because it has the potential of transmuting the spent fuels into something useful again.

As TFA points out: In 2006 France changed its laws and regulations in anticipation of this new technology, and now requires that nuclear waste storage sites remain accessible for at least a hundred years so that the waste can be reclaimed.

Transporting, burying, and sealing waste up into vaults that may be too dangerous to open, could turn out to be exactly the wrong decision.

Re:no

[KingMotley]

In the long term, all of our current methods of producing electricity is dead. Just depends on what your definition of long is, and just because it is not the perfect solution for eternity doesn't mean it isn't worthwhile until we discover something better.

Accelerator Driven Systems

[Anonymous Coward]

These have been talked about and, to a lesser extent, experimented with for at least a decade that I know of. You can use waste material from a LWR or HWR as fuel, or molten thorium suspended in lead. Fermilab did some toying around with the idea. If memory serves, the power output of throium fuel was ~17x the power input needed to run the reactor, and something in the low teens when using waste as fuel. Google "fermilab ads power" and you'll find a few conf notes.

The "problem" with such a design is that beams love to shut off without warning, for essentially no reason. Because the fuel is also kept sub-critical, this makes it extremely safe in the event of a disaster, but it's also unreliable. You would need many independent reactors to avoid random outages.

Regardless, the moral of the story is this: If something is radioactive enough to be dangerous, then it's radioactive enough to burn as fuel. There are several proposed designs that can pull this off (MSR being popular online). None are perfect. All are better than the "just store it for longer than recorded history" plan.

Re:Accelerator Driven Systems

[joe_frisch]

One could imagine building very high reliability accelerators, probably a cluster of lower power machines. Existing large accelerators can have pretty good uptimes (>95%), and there has not been a big push to do better.

It is an idea that has been kicked around for decades but now with the operation of SNS (a 1MW machine), and the European spallation neutron source (~5MW?) there are accelerators with enough power to make this feasible.

It has some great advantages: If you add a lot of neutrons to a reactor you can operate below criticality so you do not need to worry about the stability of the fuel mix (a reactor relies on delayed neutron production to have the reaction rate be controllable). This will let you safety burn fuel much more thoroughly than can be done in a conventional reactor.

The down side is the significant added cost of the accelerator and associated technical systems may make commercial designs uneconomical. It may be possible to solve this, other than average power, the beam requirements are much simpler than for most scientific accelerators and it may be possible to realize substantial cost savings.

Re:Accelerator Driven Systems

[quax]

Commercially available accelerator systems have come a long way. Also the grid infrastructure in Europe has seen massive investments to handle the power fluctuations introduced by the massive wind farms and solar.

Don't think that this poses a principal feasibility issue. The fact that you can switch this off and don't have it put out the same power at off-peak hours could actually be an attractive feature.

Re:no

[lightknight]

Haha, no. It's the only technology immediately available that can deal with a doubling of energy usage. Green technology has, unfortunately, been mostly a wash -> we blew a huge amount of the economy on its fairy-tale promises of reducing our environmental impact and creating tons of new jobs; it was meant to replace current technology with something equally as capable or better; it's nowhere near that mark. What we have, instead, is a giant bill and a bunch of green technology that might be able to put a worthwhile fight against something from the 1800s, but definitely not against something from the 1940s, let alone current technology.

Face it -> battery technology isn't there yet. Most of the green power-plants work only in certain places, under certain conditions, and many of them have an even greater environmental impact that the technology they're trying to replace. Nuclear fusion would be nice, but we still haven't cracked it. Which leaves coal, natural gas, oil, and so forth, where coal is the most popular option on the table right now; this is coal, mind you, where entire mountain mining communities are ready to vote for anyone who backs it (thus giving themselves a job), while being the biggest polluter.

With nuclear technology, the waste is contained. Yes, it's dangerous, but it's a bloody known dangerous, and as long as you do not hire someone from the bottom of the barrel to take care of it, you're pretty safe. What more, there are reactor designs, breeder reactors, which burn this waste, but are somewhat outlawed as they can be used to create weapons-grade material. Only an irrational fear of radiation keeps us from re-adopting it as a technology.

And Fukushima was an ancient reactor, build to yesterday's standards, which still held its own against a larger earthquake than it was designed to withstand. The inability to keep up with industry standards for running a nuclear reactor was a political / accounting problem, not a technology problem. You might as well argue that a B-2 bomber wasn't built to withstand a passing meteor storm; it wasn't built with that in mind, but if you'd be willing to untie our hands / remove some red-tape and give us the damn resources to fix the problem...

Re:1,000 year? 200 year? Who cares.

[HornWumpus]

Reprocessing is not the same as taking waste. What happens to the messy parts of the used fuel? What % of used fuel is reprocessed?

How much money is in the waste disposal trust fund now? Want to bet it's in federal bonds?

Re:A (VALUABLE) step

[Anonymous Coward]

Actually it has a fantastic chance of this technology "gaining a foothold" in industry... because it's expensive not because it's effective.

If "Industry" can convince legislators and environmentalists that the technology makes spent fuel less harmful (in the long run), then there's a good chance it could be written into the approved (regulated) cost structure for electrical utility companies. And since the tariffs governed by those regulators provide a guaranteed percentage return, the addition of this technology would increase the profitability of nuclear power even though there would be absolutely -0- benefit to humanity for many generations. It's not like 'customers' will have any alternative if lobbyists 'convince' legislators.

This is just the sort of sham I would expect the Big Energy to try and pull off. And any engineering companies that play in this space will be salivating like the dinner bell has already rung as well.

Re:1,000 year? 200 year? Who cares.

[HornWumpus]

A large part of the cost of Yucca Mtn was that it was designed to be monitored and the waste recovered.

That ship has sailed. We're more or less committed to breeding it away. Which is most likely the right call. Liquid sodium complications and all. We should suck it up and buy the technology from the frogs. If they don't want to sell, we'll just have to steel it.

Obligatory "Is Nuclear Waste Really Waste?"

[KonoWatakushi]

Is Nuclear Waste Really Waste? The short answer, is "hell no"; while there is a very small part of spent fuel which could actually be considered waste, the vast bulk of it is a goldmine of energy and a source of other highly valuable fission products.

It is totally silly to talk of "waste treatment" or "destruction"--this is just another way of doing fission. It is equally silly to talk about destroying enormously vast reserves of energy, just because our antiquated reactors are terribly inefficient and make a mess of the partially burned fuel. It does not have to be that way, and modern molten salt reactors like LFTR burn the fuel so completely that there is barely any waste left at all.

We need to take another look at spent fuel. Aside from burying it, which merely delays the problem, the only way to rid ourselves of it is by fissioning it. There are many ways of doing so, but the best would be to harness the energy contained within in safe and inexpensive LFTRs. Such reactors are capable of providing not only for our electrical needs, but also the production of liquid fuels, as well as process heat for water desalination, foundries, fertilizer, concrete, and more.

Certainly, fissile material like U235 and Pu239 should be disposed of, but it should be done so in a manner which maximizes its value, and fast reactors or other waste eaters are terrible in this respect. LFTRs require much less fissile material to start up, and if we were to use the fissile in this way, we could ramp up their production very quickly, and eliminate it just the same. Only this way would be safer, simpler, more efficient, and vastly cheaper.

Re:Obligatory "Is Nuclear Waste Really Waste?"

[quax]

Fair enough should probably be called "waste" recycling.

Nuclear Reactors cause Tsunamis!

[couchslug]

We should burn sweet, sweet coal instead and have No Consequences.

um, what?

[Tastecicles]

I have an antique bowl that's more radioactive than fuel glass...

Nuclear energy has the lowest death rate per TWh

[Prune]

Nuclear has the lowest deaths per terawatt-hours produced than any other significant energy production method, by a couple orders of magnitude: http://www-958.ibm.com/software/data/cognos/manyeyes/visualizations/deaths-per-twh-by-energy-sources (and yes, the figure includes all nuclear power accidents). Note that even hydro is far, far worse. Here's another, more striking, visualization: http://transitionvoice.com/wp-content/uploads/2011/03/death-rate-per-watts-Seth-Godin.jpg

Re:A (VALUABLE) step

[quax]

If the consequence of this political pork means long lasting nuclear waste gets transmuted into shorter lived waste, I won't complain.

ADSR, aka the energy amplifier or EA

[Anonymous Coward]

Search for stuff on ADSR's (accelerator driven subcritical reactor). Or the Energy Amplifier, which is patented by a CERN guy. The basic idea is (insert car analogy) a turbocharger. You have a barely subcritical reactor that by geometry of the tanks/reactor (if using molten fuels, which is a good thing by the way) can't go critical. You have a freeze plug in the tank bottom, so if it overheats, the thing drains the fuel into multiple dump tanks, which by geometry, prevent it from being critical. Now, you have an electrically driven (probably high temperature superconductor) particle accelerator at or above 1GeV firing at a (probably molten due to the particle stream) lead target in the middle of the tank, that spalls neutrons into the surrounding fuel. Fuel gets hot, heat exchangers take the heat to conventional steam generators to make electricity, some of which is fed back to the accelerator. For waste transmutation, either the waste is directly mixed into the fuel, is formed as a inner liner between the lead target and the fuel, or is in an outer liner around the fuel but before the neutron reflector. They've gotten to the point that the accelerator can use less than 10% of the gross electrical output of the generators, so it is practical. It also avoids needing highly enriched uranium or other stuff for starter fuels in a molten fuel (typically thorium).

For a molten fuel based design that is likely a pool based design, the freeze plug drain and the accelerator operation itself as a "virtual" control rod setup makes it pretty safe. You would a need a monumental disaster to cause the draining fuel to collect enough to go critical. Anything else cause the accelerator to trip, causing the reactor to essentially shutdown due to lack of neutrons, but the pool type molten reactor can stay molten long enough for the accelerator to be restarted in a reasonable amount of time (if you aren't using electric heaters to keep the thing liquid). Doesn't directly solve the remaining core heat problem of a sudden shutdown, but since it is molten by design, the dump tanks should be much more survivable compared to conventional reactors if shutdown cooling is lost.

For more

ADSR/ADS/ADTR/MSR/LFTR
https://en.wikipedia.org/wiki/Accelerator-driven_system

Professor Rubbia from CERN, now supported by Aker solutions, working on EA/ADSR
http://en.wikipedia.org/wiki/Energy_amplifier
http://cdsweb.cern.ch/record/297967?ln=pt
http://www.akersolutions.com/en/Global-menu/Media/Press-Releases/All/2010/Aker-Solutions-wins-Energy-Award-at-IChemE-for-its-innovative-ADTRTM-power-station/

GEM*STAR work at Virgina Tech
http://www.phys.vt.edu/~kimballton/gem-star/pub/w.shtml?home/overview.jpg

MYRRHA
http://myrrha.sckcen.be/

Blowups Happen anyone?

[calidoscope]

The original version of "Blowups Happen" by R.A. Heinlein centered around an accelerator driven subcritical reactor, the only way that Heinlein thought that a reactor could be made controllable at the time the story was originally written - the story was written before the discovery of delayed neutrons from fission.

Re:It's not "spent"...

[TheRaven64]

Proofreading, what's that?

It's an occupation created to solve a very important and necessary social purpose: to keep grammar Nazis off the streets.

Re:1,000 year? 200 year? Who cares.

[Anonymous Coward]

If you plan on procreating your genes will be, so your own descendants will suffer. If you want to be selfish go ahead well your screw everyone else attitude, but are you going to treat your own children the same way?

Re:1,000 year? 200 year? Who cares.

[Anonymous Coward]

You, personally, are the reason why humanity suck and will perish.

Please define "goes away"

[Anonymous Coward]

A sub-critical reactor design, driven by a particle accelerator can transmute the nuclear waste into something that goes away in about two hundred years.

Can we get more specifics in the summary, like how something that deteriorates by halving the amount remaining on average over a certain amount of time, "goes away"? Are they suggesting that for any arbitrary amount of dangerous radioactive waste, that it will be more or less completely inert and harmless after two hundred years, whether the amount that was present at the outset is 2 micrograms or 2 tons? Does the process have to continue for the entire 200 years? Or are they suggesting that they can do something that makes the waste harmless, but you still have to house it for 200 years, during which time it remains dangerous? What about after 200 years? Assuming it works, how friendly, on a scale from basilisk to unicorn, is the waste material then? Also, what happens if it doesn't work? Will we have to wait a significant fraction of 200 years to know?

Sounds pretty cool, technologically, I'm not criticizing that, if it's even close to as good as they make it out to be, but I take issue with the writing of the summary, it's poorly worded at best.

sigh.

[geekoid]

" radioactive waste that has half-lives measured in thousands of years. "
depends on the waste.
We can build nuclear systems that generator electricity using waste and it's byproduct is 200-500 years to background radiation, depending on the material used. That's background radiation, not half life.

Re:1,000 year? 200 year? Who cares.

[Anonymous Coward]

I'll be long gone by then. Let someone else deal with it. Don't waste a cent of my money on it.

Spoken like a true White Asshole.

Re:no

[taiwanjohn]

I agree on most points, but I suspect you're not up-to-date on the latest battery tech. Liquid-metal batteries offer grid-level storage at affordable prices. (Google-up Donald Sadoway's TED-Talk on this topic for more info.)

What about power requirements to run a linac?

[lightbounce]

The paper pointed to by the article (http://accelconf.web.cern.ch/accelconf/IPAC2012/papers/moyap01.pdf ) talks about needing a 1.5 GEV superconducting linear accelerator to create the neutrons. While that's not the Tevatron or LHC, it's still going to soak up a lot of power. How much of the power of the reactor will go into keeping the linac running? I didn't see any estimates in the paper.

Re:What about power requirements to run a linac?

[quax]

In other articles I've seen a 10% number floating around (don't have a link at the ready though).

Re:no

[RockDoctor]

Just depends on what your definition of long is,

I'm a geologist ; for me "long" would start at around a hundred megayears. OK?

In the long term, all of our current methods of producing electricity is dead.

Including geothermal?

Re:no

[KingMotley]

Yes. And solar too.

Re:1,000 year? 200 year? Who cares.

[cheesybagel]

How much money is in the waste disposal trust fund now? Want to bet it's in federal bonds?

It beats investing in Facebook stock.

Re:no

[RockDoctor]

Sorry but the Sun goes out on December 21st this year.

Didn't you get the email from the Mayans, or did it go into your spam bucket?

Injury Claims

[Kelvinmark]

In case of injury its always a better approach that you go can take first for your claims of compensation. Knee Injury claims