Here's a good overview of the state of thorium reactors today.[1] The Shanghai Institute of Applied Physics has been talking about building a demo unit in Singapore to be operational in 2015, but that seems to have slipped to 2017.[2]
The article glosses over a big issue - this type of reactor has to be hooked to a chemical plant which continually reprocesses the radioactive molten salt. Chemical plants for radioactive materials are historically a huge headache to operate. Many such plants are now toxic waste sites.
With BWR and PWR reactors, the radioactive portion of the system is simple, with few moving parts, and the working fluid is water. More complex large reactor designs have a poor track record. Sodium reactors have sodium fires (Monju, in Japan, was shut down after one in 1995), helium-cooled reactors leak helium (Ft. St. Vrain was a real disappointment), and pebble bed reactors have pebble jams (there's one in Germany so jammed it can't be dismantled.)
You're correct since you specified thorium reactors, but it's also possible to build very simple non-breeding molten salt reactors running on uranium. Terrestrial Energy, for example, is working on one that's designed to reach production as soon as possible.
Advantages include passive safety, no potential for hydrogen explosions, no high pressure containment, excellent nonproliferation, and reasonably high burnup. It's nowhere near what breeders are shooting for, but it's a good start.
I wish they would be more up-front about the specifics of their technical proposal and how it compares to other proposals, since it was not at all obvious to me at first glance.
What I think they're actually proposing (correct me if I'm wrong): a uranium molten salt fast breeder reactor that drives a steam turbine. So, much more ambitious than what's currently on the market, with better fuel utilization. As compared to, say, the Flibe Energy/Kirk Sorensen/LFTR crowd, it's mixed: it sounds like these folks have some new innovations around moderators and salts, and the stuff about consuming existing waste is compelling, but they're sticking with a uranium fuel cycle rather than thorium (though it sounds like they're getting proliferation resistance in other ways), and they're sticking with a steam turbine vs. proposed gas turbines that could yield some more efficiency and compactness in proposed thorium MSR designs.
EDIT: looks like I might have been wrong about the neutron temperature; their white paper says thermal, not fast.
EDIT 2: the white paper actually has all kinds of great stuff in it, now that I've read the rest: http://www.transatomicpower.com/wp-content/uploads/2015/04/t... ... In particular, it sounds like this is the first planned design, but they offer some potential future variations. They say this design could be adapted to Thorium fairly straightforwardly, but advocate uranium at least initially because of advantages in the existence of a supply chain around it and the availability of uranium spent nuclear fuel. They also mention Brayton cycle gas turbines as a possible future improvement, among others.
To get this straight, when they indicate 96% utilization of the uranium, they don't mean converting 96% of the total energy to electricity, as it is assumed that some will be lost along the way, right?
If the above statement is true, what happens to the remaining 4% of the energy in the uranium? Is it just not effective to have it in the molten salt, so the entire batch is replaced? Or does this happen 'on the fly' so to speak?
It means 96% of the uranium fuel undergoes fission (gets its nuclear potential energy converted to heat). When they separate out fission products (waste) by chemical processing, about 4% of the fuel gets dragged into the waste stream. It looks like a cost/benefit decision not to recover it:
Of the 200 kilogram lanthanide mass removed by liquid metal
extraction, we estimate that approximately 20 kilograms will
be actinide contaminant with a longer half-life similar to
SNF. It may be most practical to leave such a small quantity
embedded in the ceramic granules, as it would be well
distributed and would not materially extend the time for the
overall waste form to reach background levels. If desired,
however, the actinides can be further separated offsite with
additional post-processing techniques.
I think it means that they'll be using up 96% of the uranium but the 4% is unusable with this method. That the concentration is down low enough that they're unable to extract energy from it at that point.
96% of fissile material converted to non-fissile material, and that energy is then converted to electricity at normal steam turbine efficiency, 30% or something. This as opposed to less than 1% for Gen III reactors.
Edit: I posted that fuel handling is a batch process, not continuous – that might not be true for molten salt, not sure.
So ok, the website is cool and the technology is said to be something like 99.9999% better.
This might be a stupid question but I'm no nuclear engineer not a specialist about chemistry or physics but I wonder why a such "beautiful" idea would not be already used.
I've read the related wikipedia article about Molten Salt Reactors and I understand there are several problems about the technology: mostly corrosion and embrittlement.
So now I find myself asking this: did they fix those problems? The website copy suggests so. Can somebody explain how? I couldn't figure it out.
edit: clearly the team and company have quite legit credentials, MIT nuclear department etc... they must know what they're talking about. I just want to know if they've given details about the solution.
Probably the same reason Germany shutdown its power plants after Fukushima. Despite Fukushima being a huge success story [1] some people are scared, some unthinking, almost all irrational and unable to handle probability at all. Nuclear power seems magical and shares a word with scary weapons. It's not "natural" for mediocre definitions of natural.
1: Seriously. Fukushima did everything wrong. Huge earthquake and tsunami. Older design. Then they tried to cover stuff up. And the repair crews showed up with wrong equipment. More denial. And all that with no loss of life. Just a bit of "lost" land for a while, and extra costs. So many people freak out about it, but that US carmaker with the stupid ignition killed more people and we aren't giving up cars. Fukushima screams "hey, wee couldn't fuck this up, even given perfect conditions and terrible management". But hey, why take a rational approach when you can " go green ".
The only thing that went right with Fukushima was the wind blew the radio isotopes over the pacific (mostly) and the rest of the stuff that leaked out went into the ocean. People would be singing a different tune if the wind blew all that stuff on shore. Quite a number of nuclear plants are located in places not so fortunate. For instance consider the location of three mile island, located well inland on the Susquehanna River. If you had a containment loss at three mile island, it'd be a big big mess.
People say these plants are all safe, and newer plants are safer, but the near catastrophic failures don't give one a warm feeling. The one that stands out to me was pin hole corrosion through the cladding on the top of a reactor vessel. That lead to a large cavity corroding unnoticed in the mild steel. Which which was discovered when someone noticed an odd budge in the top. if that had failed, you would have had total loss of cooling and a melt down.
Agreed. BTW my old boss said the same after Chernobyl: he used to be worried about nuclear safety, but after Chernobyl, where everything went as much wrong as it can go - you have an unsafe type of reactor, incompetent staff blows it up, the accident is covered and evacuations are delayed, etc - and still the death toll is much smaller than the impact of coal mining, which is the practical alternative picked by e.g. Germany after Fukushima.
Fair enough, though gas imports from Russia have their environmental and human impact, too (up to and including a war in Ukraine, as the country is an inconvenient obstacle for cheap overland pipelines if it is not under Russian control in the way it was with Yanukovych).
BTW I find it somewhat scandalous that Russian gas companies can hire senior politicians (such as former German chancellor Gerhard Schröder and Finnish prime minister Paavo Lipponen) to assist the political approvals. Although these men are no longer in such official positions, it is obvious that they were given money to advance the interests of Северный поток through their connections in their respective social democratic parties.
Doesn't it take a while for people to die or see effects from radiation exposure (unless it's extreme?). Is there a reason to suspect that we won't see problems from what happened?
Also having land uninhabitable for thousands of years weighs pretty heavily even if the risk of failure is low.
They originally said it'd be a few years, but the JP government is on behind, so it might take longer to decontaminate. I don't think anyone is talking more than a decade or few. Countries sell land, so think of it that way, at worst. The clean up is also super expensive. And, over 1000 people died from evacuation-related issues. I guess that's just a factor when you move older people around, for any reason. So, yes Fukushima sucked, but in context, given the incompetence, it seems very encouraging. Unless we act even more stupid and get a large disaster, why would it be worse?
From what I've read, the estimates of cancer are really low. But you're right, there might be a few directly related deaths over the next several decades.
You'd think this would result in an attitude of wanting to push newer designs and so on, but running away is a more human reaction, it seems. :(
> over 1000 people died from evacuation-related issues.
As if the fact that a very very large tsunami hit a densely populated area did not have an impact.
Of course, a lot of people were killed by Fukushima - due to the shutdown of other nuclear reactors, which necessitated reducing electricity consumption, i.e. turning off A/C in buildings, effectively killing lots of old and weak people.
People who believe that nuclear reactors are so great and safe can probably save a lot of money by renting property next to a nuclear reactor. Have you done so? Would you like a reactor to be built next to your house?
I have actually lived half a kilometer away from a nuclear reactor. I didn't think twice about it. Itwas a small research reactor at a university campus, of course, but nevertheless, the reason I wouldn't want to live right next to a big energy production reactor is not that I would be afraid it blows up; it's that the plant is a very big building that involves a substantial amount of people, materials and security measures nearby.
That is why it makes sense to build the reactors slightly away from population centers. Not to protect the population, but to avoid annoying it with the presence of a huge energy factory.
Would you rather live right next to a coal plant? They release a lot more radioactivity into the air that a nuclear power plant. Plus, you know, all the other pollutants that they blow into the atmosphere.
Well at least people readily live next to solar power cells and even install them on the roof of their houses. Not claiming it is the solution for everything. But coal and nuclear power are not the only power sources (energy efficiency is another approach).
From my understanding it comes down to part politics, part feasibility. When nuclear power first started becoming popular light water reactors were easier to make and their fuel/byproducts aligned with the production of nuclear weapons. As years went on regulation and inertia did a great job of cementing us into our old ways. Today, advances in (material) science have made producing molten salt reactors more feasible. They also seem more attractive now that the public is generally very adverse to nuclear waste and power plant failures. I'm paraphrasing what was explained to me so someone that knows more please chime in.
That was more true in the 60's, and so we never spent the time to try bringing this to production. We don't need to make all of our nuclear reactors capable of producing weapons-grade material anymore, and I don't think there's much objection to new reactor types on those grounds.
Actually it was never true, but it makes a good story. Sorensen in particular claims the fast reactor program was favored because of its weapons applications. Nothing could be further from the truth. Fast reactors, from their conception, were pursued for sustainability reasons by pacifists like Zinn. The first electricity ever produced from fission was produced by EPR I. Every single gram of fissile in the world's nuclear weapons was made in a thermal reactor or enriched from ore. The MSR program was cancelled along with myriad other programs during the early-70's recession... including the nuclear rocket programs, the Apollo program, etc.
There has never been an economic case for the breeder simply because the fuel cycle is such a small part of the cost of nuclear energy. When you have a factor of 5,000,000 you can afford to throw away a factor of 100.
The ambiguity of "salt" is unfortunate here. The "salt" in "molten salt" is a salt, but not table salt (so, no sodium). The one proposed here is a lithium fluoride/uranium fluoride salt. Conversely, while table salt has sodium in it, the sodium in the sodium reactor isn't part of table salt, it's pure sodium metal. (Turns out they explode, also, so there's not much enthusiasm about them anymore.)
The Sodium reactor is a standard solid core Uranium fueled design that uses liquid sodium as a coolant.
The molten salt design is completely and utterly different. In a molten salt reactor the fuel itself is molten (in salt form), which turns out to offer a variety of benefits.
I wish Transatomic all the best but they have an uphill battle :( to convince a populace for whom unfortunately "nuclear power" brings up an image Homer Simpson.
aside: I think Greenpeace also has a lot to answer for with their campaign against nuclear power. Thanks to them my children can look forward to a world where a coal plant is build every week and fossil fuel fueled climate change is a certainty.
Homer Simpson and the three-eyed fish graced TV screens in 1989. In the preceding ten years, the world had seen a sequence of serious nuclear accidents: Three Mile Island, Sellafield, Chernobyl...
The smear campaign was accomplished by the companies and nations that built and maintained those shoddy, dangerous plants. Blaming Greenpeace makes as much sense as blaming them for climate change.
>...In the preceding ten years, the world had seen a sequence of serious nuclear accidents: Three Mile Island, Sellafield, Chernobyl...
Considering that it would be illegal to build a Chernobyl style plant in any other country rather than the Soviet Union, it probably shouldn't be on your list.
>...The smear campaign was accomplished by the companies and nations that built and maintained those shoddy, dangerous plants.
But even including the deaths from Chernobyl, nuclear power has been safer over the last 60 years than all other types of mass energy production: coal, natural gas or hydroelectric.
>...Blaming Greenpeace makes as much sense as blaming them for climate change.
I think the point the OP was making was that by smearing nuclear (a power source that doesn't put CO2 into the atmosphere from generating power) the alternative has usually been to build a natural gas or coal plant that does put CO2 into the atmosphere when it generates power.
If only those alternatives were actually safer than nuclear.
People die in installation and operational accidents for wind and solar at a higher rate relative to amount of electricity provided than all deaths attributable to nuclear.
And hydro has a quite horrible track record thanks to construction accidents and dam failures (even if you exclude the single worst incident - the Banqiao dam failure that killed an estimated 171,000 people).
That's not fair criticism. Greenpeace has been one of the strongest campaigners against coal plants since the 80s.
They do campaigning against nuclear power as well, for example open pit uranium mining and waste disposal processes, which might be the source of the confusion.
I am sure the industry has been held back in part due to public anxiety, but that is hardly the whole story. Whilst nuclear power maybe acceptably safe, that comes at a huge cost in terms of time, money, and complexity. If you need to acuire grid capacity in the short term these are major issues. In the longer term all we hear are new unproven designs that require massive investment just to prove a concept.
United States is only 25% of the market for electricity production. There are 185 other countries that use electricity. I don't think Transatomic will have trouble finding countries that are willing to move sooner.
>I think Greenpeace also has a lot to answer for with their campaign against nuclear power. Thanks to them my children can look forward to a world where a coal plant is build every week and fossil fuel fueled climate change is a certainty
at least your children can look using 2 eyes. If not for Greenpeace the expected value would be uniformly distributed anywhere between 0 and 4 or 5...
Coal contributes vastly more to radioactive environmental contamination than nuclear does, by hurling radioactive particles into the atmosphere. So on the contrary, the fear over nuclear has done far more to increase our exposure to radiation that what we would have if coal plants had been replaced by nuclear.
How is that relevant? That coal plants deaths are spread over the entire world does not make them less lethal.
The deaths caused by Chernobyl is a tiny blip compared to coal no matter whose estimates you pick.
In 2010 alone, estimated deaths from US coal power plants alone was 13,000, with a huge number of other bad health effect (20,000 heart attacks for example) [1]
In the 3 decades from Chernobyl we can extrapolate to maybe ~350k-400k deaths from US coal plants alone.
The number of deaths due to Chernobyl on the other hand, is rarely estimated higher than the low tens of thousands. The number of cancer incidents attributable to Chernobyl is likely far higher. E.g. estimates of an excess 7k thyroid cancer incidents in Belarus, Ukraine and Russia by 2005. But only a small number of those have died of cancer so far (the number will likely increase, but the reduction in overall life expectancy is still modest).
In 2005, the UN predicted 4,000 deaths due to Chernobyl [2]. Greenpeace countered with a claim of up to ~300k deaths total[3] (based on a combination of an estimated 93k deaths in Belarus and 60k deaths in Russia due to cancers, and an additional estimate of potentially another 140k premature deaths in the following/coming years).
Even if we accepts the Greenpeace claims, as the upper boundary, more people have likely died due to US coal plants alone than due to Chernobyl in the years since Chernobyl.
And the US is not the biggest consumer of coal. Already well before 2000, China had surpassed US coal consumption. Tack on India and Russia, and the US coal consumption is only 1/3 of that used by the top 4 countries. Go to the top 10, and the US coal consumption made up ~25% by 2000, and as far as I know dropping as a percentage of overall consumption due to dramatic continued growth in places like China. So even just looking at the top 10, it would not be unreasonable to quadruple the estimates of excess deaths from coal from the above to 1.4-1.6 million in the 3 decades from Chernobyl.
But of course these plants were going for decades before that, and will continue for decades to come, and many of these countries have far more lax rules than the US when it comes to emissions. The reality is that worldwide deaths from coal likely are equivalent to Greenpeace's idea of Chernobyl every 2-5 years. On the other hand, if the UN predictions are right, US plants alone are as lethal as 3 Chernobyl's every year, and coal worldwide is equivalent to somewhere well above 12 Chernobyl's every year.
Now, it is reasonable to bring up that Chernobyl is only one plant, but the point is the difference is damage scenarios: Nuclear plants kill when something goes wrong, and something goes wrong exceedingly rarely, leaving us able to name the ones attributable to 90%+ of nuclear power related deaths.
Coal plants, on the other hand, silently kills every day, around the clock, during normal operation. Chernobyl, even accepting the worst case estimates, does not lift nuclear even into the same league. Even if we replaced coal with Chernobyl type reactors, with the same lax safety procedures as at Chernobyl, rather than opt for the much safer designs and processes that were the norm even back in 1986, we'd still kill far fewer people.
It's always interesting to see how these companies can progress in a year[0]. Regardless though, for those curious, there's a great presentation by the CEO, Dr. Leslie Dewan on what TPT does differently[1]. The big selling point for their Molten Salt Reactor (compared to others) is that they designed it to be able to use low-enriched Uranium (fresh fuel, as opposed to spent fuel) and nuclear waste. The downside of this is that it can't produce the same volume of electricity that a normal nuclear plant can, but it's significantly safer, and can't be used to produce weapons grade uranium.
For those interested in MSR's this serves as a good starting point too[2].
So this is a company with a pretty ui that is advocating the same thing Kirk Sorensen has been advocating for a few years now.
I know every time this molten salt vs light water reactor debate comes up, people much smarter than I talk about how the salt is corrosive and there are currently no viable solutions to deal with this. Is there anyone out there smarter than I that can explain whether this company is doing anything different, or if it is just sexy and VC backed?
They say the modified Hastelloy-N from the Oak Ridge experiment is good enough, though I suppose people who disagreed with that claim when it was presented by previous MSR advocates would still disagree now. They do also mention in their white paper, though, that it may eventually be possible to replace some of the Hastelloy-N with ceramic composites, which might be better still.
The zirconium hydride moderator is a genuine innovation, allowing much higher core power density than LFTR, and higher conversion ratios without HEU (assuming their modeling is correct). But like LFTR, you've got loose FPs all over the place and it's hard to see that being acceptable in anything like the current culture. Meanwhile, it's hard to see any benefit from MSR.
Edit: There will likely be all sorts of materials issues. None of them damning. I'd worry more about FPs, tritium fluoride, etc. than the salt itself.
Nope. Gaseous FPs are continuously removed and stored somewhere. Of course they require cooling while being stored. Any mishap releasing even a tiny fraction of them would of course be harmless, but in the present culture would result in a global panic.
Other FPs in the salt are circulated out of the core and through a heat exchanger. Some ongoing actinide fission there too. Tiny defects in heat exchangers handling plain water currently cause reactors worth billions to be abandoned (e.g. SONGS).
Some FPs will plate out and you'll need to replace plumbing periodically. That has to be done by robots because the pipes will be ultra-hot and deadly within minutes to anyone nearby.
For what benefit? You improve the fuel cycle by a factor of 50. But the fuel cycle is < 10% of the costs and material flows of nuclear plant. So yes, online FP separation is something a mature fission-based civilization would have. But it is not clear how it helps us, other than to provide a focal point for a new culture to form (which may be a substantial if illegitimate benefit, admittedly).
Well ok that's true. On the other hand, removing fission products means you have a lot less decay heat to deal with upon reactor shutdown. Dump the fuel to a tank without moderators and walk away.
ThorCon has an interesting approach for dealing with plating and so on: their design has reactor cores that can be easily swapped out. When one's ready for maintenance they just cart it away, let it cool for several years, then deal with it.
There are certainly solutions to deal with it by designing for leaks as an expected maintenance problem, though preventing them would obviously be preferable. There are numerous operating molten salt reactors around the world, so I guess it depends what you mean by viable: http://en.wikipedia.org/wiki/Breeder_reactor#Breeder_reactor...
Note that this is note exactly the same thing, Sorensen has been advocating a Thorium fuel cycle, these folks seem to be advocating a Uranium fuel cycle.
In the absense of renewables, the promise of more efficient nuclear electricity production sounds great. It's just that this promise has been around since the 50s and instead we now have huge amounts of highly toxic nuclear waste.
The potential of wind, especially in the States, is so significant and threatening to anyone stupid enough to invest their time in developing nuclear power plants at a time when the price for renewables has undercut nuclear and coal.
This video makes it all look a little too easy. The nuclear industry is with its back to the wall and for very good reasons. The core message here is: let's build more nuclear power plants and we can sort things out. We have been hearing those types of arguments for over 60 years. The technology has left us with huge amounts of incredibly toxic waste and recycling experts in France/UK/US still haven't been able to sort this out. So here are wonderboy and wondergirl telling us they sorted it out. Hm. Who doesn't like a good miracle.
I am not a nuclear physicist, but isn't this concept proven and well-understood already?
Now, a sales pitch is indeed a missing piece. Given the regulations, the nuclear industry is stuck with power plants whose designs date from decades back.
I didn't see anything about handling the waste heat though. Dumping it into rivers would be atrocious. Ingesting large amounts of water to use evaporation towers is also environmentally terrible. I hope they thought of that.
I am all for the responsible use of nuclear power. Greenpeace and the like made so much noise that the public is afraid of anything called "nuclear". The media doesn't help, either.
The result is far more deaths every year due to coal and other fossil burning. Let's do more solar and wind, sure, microgrids and other cool stuff. Nuclear can provide the baseline power and power for power-hungry industries, such as aluminium refineries.
Waste heat dissipation is a problem for all thermal power generation schemes. The use of CHP to provide residual heat for nearby residential heating/industrial use boosts the overall efficiency of the system, but with higher upfront costs.
While it's neat to see more companies jumping on board, what they're looking at isn't really revolutionary, despite the polished PR on the website. There are lots of companies, research organisations etc working on molten salt reactors. Lots of them, including Oak Ridge National Lab (http://www.forbes.com/sites/jamesconca/2015/01/07/nuclear-po...).
On the surface, this seems kind of like launching an IaaS cloud service and claiming you're introducing something new and innovative.
Well, it's not like there would only be room for one company on the market. The problem with nuclear power is fundamentally a marketing problem, and the winners in the market will be the companies that can successfully distance themselves from the disasters of the past. It's going to be less about fundamentally new technology and more about how well you can market yourself to people who associate nuclear power with Chernobyl and Fukushima Daiichi(which is anyone who hasn't studied the subject extensively). You're especially going to run into problems with the NIMBY crowd. Given their landing page I would have a modicum of faith that they understand this.
The more the merrier, imo. If they can do a better job at PR, marketing and "branding" than the more stilted organisations doing the same thing, then they can speed up the changing of public perceptions and speed up eventual adoption.
The bigger problem than the corrosion is the inability to inspect the system in an efficient way. In a regulated nuclear industry, not knowing the status of the system means it will not be allowed.
Given that the system has intrinsic safety built in, I'm not sure why regular inspection would be required.
Perhaps the NRC does require regular inspections for existing plants, but none of those existing plants are failsafe are they? If something starts to go wrong, it can snowball very quickly into a much worse situation.
With a MSR the worst-case scenario (short of terrorism) is that you empty into the dump tank until you sort the problem out and restart. If you make the entire facility's floor the dump tank then inspections are going to be rather redundant. Except perhaps to ensure that the dump tank is intact. But that can be made fairly easy I think.
I think there is a tendency to think of fuel rods as a problem rather than the solution to a problem, which is raw spent fuel is nasty. The cheapest and easiest way to deal with spent fuel is to store it for decades while the worst of the radio-isotopes decay. Fuel rod technology allows you to do that, a molten salt design doesn't. I'm okay with this argument but is seems to bother people that you can't recover spent fuel now rather than waiting 25 years so they cast about for solutions to what is really a psychological annoyance.
See the quest for reusable launch systems like the space shuttle.
The funny thing about nuclear waste is that it's not the "hottest stuff" you have to worry about. The hottest stuff has a very short half life and disappears relatively quickly. On the other side things like Carbon 14 that have a multiple millennium half life are not radioactive enough to cause much of a problem. It's the stuff that has a half life of about 10 to 1000 years that you have to worry about.
What about Spallators? Are they being worked on seriously by anybody nowadays? I liked the idea of subcriticality and the low radioactive lifespans in the waste. But how efficient could the be?
And related, is transmutation of waste being worked on?
I'm optimistic with what "modern technology and materials" can improve upon previous attempts [1]. Yet I hope they drastically over engineer their safety standards given historical failures.
Perhaps something the countries signing on to the Global Apollo Programme[1] should be investing in. It's priorities are Renewable/Storage/Smart Grids, but I don't think we should be ruling anything out, if 2C is the target.
Thorium msrs could be a panacea for humanity - but they won't get adopted, because nuclear weapons aren't a byproduct, and that's a drawback in the eyes of our bellicose political classes.
Edit: you're welcome to downvote the truth, but it won't change it.
This is the technical summary:
"A lithium fluoride – uranium fluoride fuel salt, moderated with zirconium hydride, would allow our reactor to remain critical with a loading of used nuclear fuel."
You're probably being downvoted for saying that reactors make nuclear weapons. They don't. They might be able to produce materials to build a weapon, but it's not like they pop out little bombs. Considering some folks equate "nuclear power plant problem" with "nuclear bomb explosion", this is a nontrivial distinction.
The question though is whether the fissionable material is usable for weapons in any practical sense.
In the Integral Fast Reactor, for example, you end up with a mixture of the four isotopes of plutonium. It's impossible to use that mixture for weapons, and it's much harder to isolate the Pu239 than it is to enrich natural uranium.
In some thorium designs, the fissionable U233 (bred from thorium) is mixed with U232, which is also very hard to separate and makes the material unworkable for weapons. (However, this is not true of all thorium designs. Chemically separate the protactinium and it will decay to pure U233.)
If you had one of the nonproliferating designs and were silly enough to attempt using it for weapons production, you would need much larger and more sophisticated enrichment facilities than if you just enriched natural uranium. If you get your startup fuel from other countries, you can forgo enrichment facilities entirely, making it very clear that you don't have a weapons program.
they don't need to prove that it would work - that is pretty well known. What they would need to prove for the idea to make any progress toward real-world implementation is that their good economy of neutrons isn't that good as to allow say to dissolve additional amount of U-238 (widely available to almost anybody anywhere) and get Pu-239 on the other end or any similar reaction :) Their ability to consume very low-enriched U-235 isn't an advantage here as the typical reactors necessity for the high-enrichment is what blocks and allow to identify weapons programs around the world.
The article glosses over a big issue - this type of reactor has to be hooked to a chemical plant which continually reprocesses the radioactive molten salt. Chemical plants for radioactive materials are historically a huge headache to operate. Many such plants are now toxic waste sites.
With BWR and PWR reactors, the radioactive portion of the system is simple, with few moving parts, and the working fluid is water. More complex large reactor designs have a poor track record. Sodium reactors have sodium fires (Monju, in Japan, was shut down after one in 1995), helium-cooled reactors leak helium (Ft. St. Vrain was a real disappointment), and pebble bed reactors have pebble jams (there's one in Germany so jammed it can't be dismantled.)
[1] http://www.world-nuclear.org/info/current-and-future-generat... [2] http://www.ornl.gov/ornl/news/news-releases/2015/ornl-and-sh...