Updated Wiki on liquid fluoride thorium reactor

[Cyril R]

I've updated and heavily edited the Wiki article on liquid fluoride thorium reactor (LFTR). It's a quite nice and comprehensive article if I may say so.

en.wikipedia.org/wiki/Liquid_fluoride_thorium_reactor

[Barry Brook]

Cyril, off topic, you should register on this forum if you are going to continue to post here. You can then llogin to your account and post from that - you won't need to enter the SPAM check each time, and all your posts will be archived etc. All the cool kids are doing it...

BTW - when you do register (Mod talking now) be sure to register as cyrilr(all lower case, no gaps etc) you can alter your name to Cyril R in your membership details after you have registered. Many, including I, got caught (frustratingly) with the lower case enrolment necessity.
Great to have you on board ;D

[eclipse]

Can I just ask a dumb question? Does a thorium reactor need plutonium in the fuel cycle somewhere? The reason I ask is this piece about India's planned FBR for next year seems to hint it.

The Minister, however, said on account of non-existence of any fissile isotope in naturally occurring Thorium, unlike that existing in Uranium, commercial utilisation of Thorium, on a large scale, can begin only when abundant supply of either Uranium or Plutonium resources are available.

"Therefore, considering meagre domestic uranium resources in the country, it is feasible to start significant commercial level Thorium-based reactor programme in our country only after an adequate inventory of Plutonium becomes available from our fast-breed reactors, comprising the second stage of Indian nuclear power programme," he said.

www.ndtv.com/article/south/kalapakkam-nuclear-power-plant-to-be-commissioned-next-year-572272

[David B. Benson]

eclipse --- Yes, U or Pu is required for startup.

[eclipse]

Hi all,
do you have a favourite youtube doco on LFTR's?
I sat through this one, but it felt a bit 'Blair Witch' in the production values if you know what I mean. I learned a lot, and pushed it in the Australian Christian Environment group on Facebook. I dared them not to fall in love with nuclear power after watching this, and one guy came around! But sadly, of course, the very next doco I watched said LFTR's are probably 10 years of heavy R&D away. GE seem to have the S-PRISM ready to go, but that's an IFR. IFR's don't have the same sex-appeal to people freaked out by sodium burning and fizzing in water at the beginning of this doco!
www.youtube.com/watch?v=8Pyq8kCeiYs

[huon]

eclipse- I recommend the following video. Leslie Dewan, who helped develop Transatomic's reactor, is a wonderful spokeswoman for her reactor, and for modern nuclear in general. The Transatomic power plant can use thorium, as well as nuclear "waste" and uranium.

www.youtube.com/watch?v=4UXXwWOImm8

[eclipse]

Hi Huon,
LFTR's can eat nuclear waste and warheads, can't they?

[huon]

Hi eclipse,

My layman's understanding is that burning up nuclear waste, as the Transatomic reactor does, requires a fast reactor. Thorium reactors are thermal, with slow neutrons. So I don't think they'd get much nourishment from waste. They might be able to snack on weapons, though.

[eclipse]

At about an hour and 4 minutes in (1:04) Kirk Sorenson says we should put plutonium and old nuclear warheads in a "Lifter". That's how he says LFTR, which I think is cool. Lifter. The reactor that can lift this whole civilisation out of dirty energy poverty and into clean energy abundance. I like it!
This 2 hour documentary is my favourite so far: it takes a lay person like myself right through the history of the first reactors, trouble dealing with Xenon135, the original ideas behind a nuclear air-force! and how that lead to LFTR.
www.youtube.com/watch?v=P9M__yYbsZ4

[eclipse]

Hi all,
The 2 hour documentary above was very encouraging when Kirk started talking about the Chinese delegation sent to investigate Oak Ridge. Basically, now I'm wondering if we need to promote the IFR any more? I know the IFR has had decades more development, but now that the Chinese are going to fast track the LFTR, don't we have an opportunity to move to true passive safety? Where gravity never fails, and the reactor always drains to the drain tank, every time the power fails? Every time? Given that it's going to take decades to get enough fissile material to run a world of IFR's anyway, should we be uniting our campaign around something like the AP1000 and then mass producing that while all agreeing that the ultimate goal is the LFTR?

The nuclear race is on. China is upping the ante dramatically on thorium nuclear energy. Scientists in Shanghai have been told to accelerate plans (sorry for the pun) to build the first fully-functioning thorium reactor within ten years, instead of 25 years as originally planned.

“This is definitely a race. China faces fierce competition from overseas and to get there first will not be an easy task”,” says Professor Li Zhong, a leader of the programme. He said researchers are working under “warlike” pressure to deliver.

Good for them. They may do the world a big favour. They may even help to close the era of fossil fuel hegemony, and with it close the rentier petro-gas regimes that have such trouble adapting to rational modern behaviour. The West risks being left behind, still relying on the old uranium reactor technology that was originally designed for US submarines in the 1950s.

The excellent South China Morning Post trumpeted the story this morning on the front page of its website.

As readers know, I have long been a fan of thorium (so is my DT economics colleague Szu Chan). It promises to be safer, cleaner, and ultimately cheaper than uranium. It is much harder to use in nuclear weapons, and therefore limits the proliferation risk.

There are ample supplies of the radioactive mineral. It is scattered across Britain. The Americans have buried tonnes of it, a hazardous by-product of rare earth metal mining.

As I reported in January 2013, China’s thorium project was launched as a high priority by princeling Jiang Mianheng, son of former leader Jiang Zemin. He estimates that China has enough thorium to power its electricity needs for “20,000 years”.

The project began with a start-up budget of $350m and the recruitment of 140 PhD scientists at the Shanghai Institute of Nuclear and Applied Physics. It then had plans to reach 750 staff by 2015, but this already looks far too conservative.
The Chinese appear to be opting for a molten salt reactor – or a liquid fluoride thorium reactor (LFTR) — a notion first proposed by the US nuclear doyen Alvin Weinberg and arguably best adapted for thorium.

This in entirely different from thorium efforts in the West that rely on light water technology used in uranium reactors. The LFTR has its own problems, not least corrosion caused by the fluoride.

“We are still in the dark about the physical and chemical nature of thorium in many ways. There are so many problems to deal with but so little time,” said Prof Li.

The great hope for thorium is that it could restore faith in the safety of nuclear power after the Fukushima disaster. It can be done on a much smaller scale, at atmospheric pressure, without the need for the vast structures than encase uranium reactors. You could have micro LFTRs for each steel mill or a small town, hidden away, almost invisible.

The British have an (underfunded) research project – ThorEA – anchored at Huddersfield University under Professor Robert Cywinksi. He says the technology is intrinsically safer since the metal must be bombarded with neutrons to drive the process. “There is no chain reaction. Fission dies the moment you switch off the proton beam,” he told me.
Thorium may at least do for nuclear power what shale fracking has done for natural gas, but on a bigger scale, for much longer, and with near zero carbon dioxide emissions.

China’s thorium drive is galling for the Americans. They have dropped the ball. As I reported last year, the Oak Ridge National Laboratory in Tennessee actually built a molten salt thorium reactor in the 1960s. It was shelved by the Nixon Administration. The Pentagon needed plutonium residue from uranium to for nuclear bombs. The imperatives of the Cold War prevailed.

The thorium blueprints gathered dust in the archives until retrieved and published by former Nasa engineer Kirk Sorensen. The US largely ignored him: China did not.

Mr Jiang visited the Oak Ridge labs and obtained the designs – entirely legitimately – after reading an article in the American Scientist extolling thorium. His team concluded that a molten salt reactor may be the answer China’s prayers. It is playing out just as he hoped.

The Chinese are currently building 28 standard reactors – by far the biggest nuclear push in the world – and working on several research and development fronts at once. This is to break what it calls a “scary” dependence on imported fuel, but also to fight pollution.

The Hefei Institute of Physical Science in Anhui has just finished building the world’s largest experimental platform for an accelerator reactor that burns nuclear fuel with a powerful “particle gun”.

Professor Gu Zhongmao from the China Institute of Atomic Energy cautioned against too much exuberance on so-called fourth-generation reactors. “These projects are beautiful to scientists, but nightmarish to engineers,” he told the SCMP.

blogs.telegraph.co.uk/finance/ambroseevans-pritchard/100026863/china-going-for-broke-on-thorium-nuclear-power-and-good-luck-to-them/

[Roger Clifton]

Eclipse, your correspondent speaks with forked tongue. He allows us to gather that uranium reactors are not safe, clean or cheap. He implies that their product can be used in nuclear weapons and presents a proliferation risk.

Neither is he respectful of thorium. He leads us to believe that the metal is hazardous and has to be buried. Having implied that both thorium and uranium reactors are unsafe, unclean and uncheap, he then goes on to suggest that small versions of the LFTR (baths of radioactive liquid!) could end up at every steel mill and small town. We are expected to shudder at the idea.

It seems to be an hoax by and presumably among the antinuclear brigade.

By the way, AP1000s are not easily mass produced because they require massive forgings. It is the SMRs, the small modular reactors, that are designed so they can be mass produced under licence in any industrialised country. See BNC thread on SMRs.

[eclipse]

"they require massive forgings"
Ooo ooo! (Arnold Horshack noises from "Welcome Back Cotter"). I think even I know what that means! 
Are you talking about the 6 inch thick single mould required for the Shell Flanges for Reactor Pressure Vessels? 
Kirk really learned me good. 



OK, thanks for the heads up. These things designed for 70 atmospheres up are not so easy to mass produce. SMR's at one atmosphere are! Good stuff.

[eclipse]

This one was *really* interesting. Jiang Mianheng (son of former Premier of China!) takes half an hour to explain why China is pursuing nuclear energy and especially thorium energy. As well as the usual *rave* about thorium's incredible energy density, the Molten Salt Reactor's ability to eat nuclear waste, and the fact that it *cannot* melt down, he also talked about “Who killed the electric car?” He said it was a very scary story, and compared it to something that sounded like “World War 2 Nazi’s” but I couldn’t quite catch it as his accent was a little thick here. Anyone good at lip reading? (The audio and video get a little out of sync, but you can see him say it).
www.youtube.com/watch?v=TZD1zfW4E1s

[eclipse]

Can I just ask a dumb question? I've been quite happy that breeders 'eat' nuclear waste: but what about the coolants? Don't they become radioactive? How do we process all the sodium from an IFR or fluoride from LFTR's?

[David B. Benson]

eclipse --- Neither sodium nor helium nor lead-bismuth have radioactive isotopes and do not fission.

[eclipse]

Sure, but I thought things could 'pick up' radioactivity? Not sure what the terminology was. Don't containment vessels and other metal bits and non-radioactive (in and of themselves) parts of a reactor become radioactive?

[Roger Clifton]

Dec 23, 2014 18:26:28 GMT 9.5 eclipse said:

Don't containment vessels and other metal bits and non-radioactive (in and of themselves) parts of a reactor become radioactive?

Although minimised during design, many reactor materials do have isotopes that absorb neutrons, with various probabilities in proportion to their "thermal neutron absorption cross-sections".

To answer the question of whether that makes a problem, you could explore their different values in the last column, "Abs xs" of the table: www.ncnr.nist.gov/resources/n-lengths/list.html. When you figure an absorption is likely, check elsewhere whether the resulting isotope (ie with an extra neutron) has a beta decay, and if so, if its half-life is long enough to be of concern. In the process you'll see one reason why fluorine is preferred over chlorine for LTFR.

[eclipse]

Moltex in the UK claim they could build an MSR with almost off-the-shelf parts as soon as they have the money.
Anyone got contacts near Elon Musk?

6 minute video does justice to the MSR.

www.youtube.com/watch?v=R4GSDRqah-0

[Greg Kaan]

Dec 25, 2014 19:43:13 GMT 9.5 Roger Clifton said:

To answer the question of whether that makes a problem, you could explore their different values in the last column, "Abs xs" of the table: www.ncnr.nist.gov/resources/n-lengths/list.html. When you figure an absorption is likely, check elsewhere whether the resulting isotope (ie with an extra neutron) has a beta decay, and if so, if its half-life is long enough to be of concern. In the process you'll see one reason why fluorine is preferred over chlorine for LTFR.

Another thing to note is that this table provides cross section data for THERMAL neutrons. www.ncnr.nist.gov/resources/n-lengths/
The vast experience with moderated reactors makes this the most relevant information for most current reactor environments

The fast neutron relative cross sections are almost always quite different and as a result, optimum material choices are also different.

Kirk Sorensen has a nice article with discussion about chloride and fluoride salts and their suitabilities for fast and thermal reactors. energyfromthorium.com/2016/01/16/doe-terrapower/

The LFTR is moderated for thermal neutrons hence the much greater suitability of fluoride salts.