Energy From Thorium Discussion Forum

It is currently Sep 21, 2018 5:20 am

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 47 posts ]  Go to page Previous  1, 2, 3, 4  Next
Author Message
PostPosted: Jun 10, 2016 11:14 am 
Offline
User avatar

Joined: Dec 22, 2015 8:40 pm
Posts: 359
Location: Florida
Exactly on the tritium. If Dr. Weinberg and the Oak Ridge boys thought worthwhile the subject avenue of using neutrons to deplete TONNES of lithium, they may have written on it; evidently the Li-6 needed for H-bombs drove COLEX (Hg amalgam) column exchange process. But did the MSBR engineers get their Li-7 purified from the Y-12 tails?

Why are so many second guessing Dr. Alvin Weinberg? Dr. Eugene Wigner? Dr. Glenn T. Seaborg? Who on this forum has similar records of achievement? And their vision is OUR vision here. COLEX was an expedient. I (graduated in chemistry) bet Dr. Seaborg (a chemist) would have lauded and totally supported these ionic liquid methods.

IF demand for HD Li suddenly appears, who wants to bet against an ionic liquids separation process will get the job done? Who wants to work with a mercury process? I don't! Are the new ILs less expensive than crown ethers? I bet they are!

Dr. Stephen Boyd is also a chemist. He has been featured along side Kirk, David, and the other champions of this superior energy technology. Does his secret HD lithium process use ionic liquids? I guess we'll find out if LFTR gets built, proved, demanded, and then Havelide Systems shows up to supply.

Kurt, we don't know each other so it's hard to interact here in writing without the benefit of familiarity. Let's assume that you and I are great people and have fun hanging out on this crucial issue. I'm not interested in ego or fame or getting rich or "I told you so" bragging rights--NOT YOU!--just I can only speak for myself. I've lived a full life already. I'm concerned about the world my grandniece (in her 20s) and her children will inherit--all the children of the coming generations. I suspect you feel similarly otherwise you wouldn't be on this forum?

You put your money on neutron bombardment. Have you read Kirk Sorensen's 2014 masters paper at UT-Knoxville? Have you read the paper Jim and I were discussing? I hope you can find a couple of hours to watch Gordon's new film that is really good:

"NASA" - THORIUM REMIX 2016

If and when you watch this new Thorium Remix, post any review there? I hope you agree that Gord's film ought to receive a wide viewership. All of us pro-LFTR people here are in this choir preaching to one another. We need to make converts out there in the electorate.

This discussion was supposed to resume on Lithium-7, remember? But maybe this is the better place for this discussion.

HD lithium supply is one serious hold-up on the deployment of LFTR. Another is the LFTR moderator. Aside from technical challenges, the greater hold-up is the entrenched solid-fueled uranium fuel cycle industrial capture of the U.S. DOE and NRC.

_________________
"Those who say it can’t be done are usually interrupted by others doing it."

—James Arthur Baldwin, American novelist, essayist, playwright, poet, and social critic


Last edited by Tim Meyer on Jun 27, 2016 5:02 pm, edited 1 time in total.

Top
 Profile  
 
PostPosted: Jun 10, 2016 12:07 pm 
Offline
User avatar

Joined: Dec 22, 2015 8:40 pm
Posts: 359
Location: Florida
Jim L. wrote:
However, the huge elephant in the room will be the NRC - sometimes I swear that they worry more about tritium than U or Pu!!
Jim, Kurt, everyone: Based on the tone of the DOE/NRC Workshop on non-LWRs this week, it appears that a major shake-up is gonna be needed. Not "huge elephant" rather Godzilla!

_________________
"Those who say it can’t be done are usually interrupted by others doing it."

—James Arthur Baldwin, American novelist, essayist, playwright, poet, and social critic


Top
 Profile  
 
PostPosted: Jun 10, 2016 12:37 pm 
Offline
User avatar

Joined: Dec 22, 2015 8:40 pm
Posts: 359
Location: Florida
Kurt Sellner wrote:
Tim Meyer wrote:
Maybe you can find the post where Dr. David LeBlanc here gives the equivalent price for neutrons.
I did . . .
C'mon, Kurt! No. You did NOT! If you had, you could have found what I found:
At Re: Comments on paper? Dr. David LeBlanc wrote:
Regarding the "cost of neutrons" curiosity. . . . Yikes! A billion dollars a kilo? That is much bigger than I thought the accelerator folks were claiming.

In terms of ball parking a guess, I don't think you can really look at the price of electricity the neutrons generate because you'd never give up power at a reactor just to make isotopes. What you do give up though is that neutron potentially making a extra fissile which extends the life of the fuel (or conversely means you need less fissile to begin with to get the same lifetime). Hmmm, is it that simple?

Excess non-fission causing neutrons either make a new fissile or are lost to parasitic losses or leakage. In a PWR making a fissile is about 60% of the time (eta about 2.0 and conversion ratio about 0.6). So 1 gram of neutrons means not making 0.6 x 239 grams of fissile Pu239 so we'd need to have roughly 143 grams more fissile in the fuel to compensate. A rough price for fissile is $30/gram so a gram of neutrons means you have to spend $4,300 more for fissile. About $4 million a kg. Hmmm, why is that so much higher than MikeGospodin's estimate using loss of electricity sales? Something doesn't make sense.

Going back to the power loss angle. One GWe year burns about 1000 kg [1 tonne] of fissile. This would need about 4 kg of neutrons (1 kg of neutrons fissions 235 kg of U235) to fission all that (plus another 4 kg that are lost or make Pu239). Looks like this way also gets one to the millions per kg level, too. Many millions if you look at the full value of electricity (not just the value of fuel). I can't quite follow MikeGospondin's logic but I think there must be a glitch.

Looks like neutrons are pretty pricey items any way you look at it but the accelerator-produced ones seem no where near "market" value.

Okay, as I go to post, Mike has found the glitch himself and gets $310 million/kg, which makes sense by the power lost angle. I think the extra fissile needed is the better approach. So a cost of $4 million/kg might be closer (of course isotope makers have all sorts of other costs so you can't use this as much of a guide).

David L.
Kurt, neutrons are extremely expensive: ~$4 million/kg! The whole nuclear industry is neutron-conservative.

You answered Jim and obviously ignored me. Dude! You persisted in neutron bombardment method for HD lithium that was mused by Torres, the author of this topic. Clearly it's a bad idea. You and I are not experienced nuclear engineers or Nobel scientists. We yield to those who've done the work and have the experience. You and I are "Clash of the Morons" compared to Kirk Sorensen, Dr. David LeBlanc, never mind Dr. Eugene Wigner, physicist and chemical engineer who invented this whole LFTR technology with Dr. Alvin Weinberg, and especially Dr. Glenn T. Seaborg, Nobel-prize-winning chemist who used chemical methods in his nuclear discoveries!

Besides, I earned my masters in chemistry (1987). You? I'm talking a promising chemical method for high-depletion of lithium for LFTR. And who are you to challenge that? What's your problem?

_________________
"Those who say it can’t be done are usually interrupted by others doing it."

—James Arthur Baldwin, American novelist, essayist, playwright, poet, and social critic


Top
 Profile  
 
PostPosted: Jun 10, 2016 5:49 pm 
Offline

Joined: Nov 14, 2013 7:47 pm
Posts: 574
Location: Iowa, USA
Tim Meyer wrote:
Kurt, neutrons are extremely expensive: ~$4 million/kg!

If I did my math correctly that equates to about $40,000/kg of high purity heavy lithium. Expensive for sure but also within an order of magnitude of the estimates I've seen for obtaining heavy lithium from other means.

What you seemed to miss was that I did not necessarily propose that neutron bombardment be the sole means by which we could obtain pure heavy lithium. From what I can tell neutron bombardment is technically feasible, and potentially economic, but far from desirable. I can foresee neutron bombardment being used as one step in the process to get high purity lithium. It appears that we'd need 5 or 7 nines of purity in the Li-7 salt for a LFTR. Neutron bombardment might be one step in the process with a different process to finish, perhaps use bombardment to get the first 3 nines of purity then use something else to get the last 3 nines.

If I understand Dr. LeBlanc correctly LFTR does not need 6 nines of pure Li-7 to operate. It may be possible to start the LFTR with 3 or 4 nines but the starter charge would have to have a higher enrichment to the uranium to make up for it. Those very expensive neutrons may look cheap by comparison if 3 nines pure lithium salts come at $1000/kg and 6 nines purity costs $100,000/kg. It might even look good with the lower purity lithium at $10,000/kg.

Tim Meyer wrote:
You answered Jim and obviously ignored me. Dude!

I'm sorry if you feel like I've ignored you but I don't often have much time to comment. I have a few minutes now while supper is in the oven but I may not have that time in the future. Don't feel insulted if I must pick and choose who I reply to, I comment when and where I have something to say and the time to say it.

Tim Meyer wrote:
You persisted in neutron bombardment method for HD lithium that was mused by Torres, the author of this topic. Clearly it's a bad idea. You and I are not experienced nuclear engineers or Nobel scientists. We yield to those who've done the work and have the experience. You and I are "Clash of the Morons" compared to Kirk Sorensen, Dr. David LeBlanc, never mind Dr. Eugene Wigner, physicist and chemical engineer who invented this whole LFTR technology with Dr. Alvin Weinberg, and especially Dr. Glenn T. Seaborg, Nobel-prize-winning chemist who used chemical methods in his nuclear discoveries!

We both admit to be amateurs here, there are few on this forum that are true professionals. I don't claim to question the work of these giants, I just think that there appears to be some disagreement on this and, in a sense, I've picked a side on this debate.

From what I have read it appears that neutron bombardment is not something to rule out completely just yet. As Mr. Sorensen has pointed out in one of his talks when it comes to getting investors it's not the size of the check that matters as much as the risk. Many of the processes being discussed here are theoretical, neutron bombardment has many more known factors than others. Experimentation with actual nuclear devices has shown how neutron bombardment works. That is why I believe that neutron bombardment will likely win in the early battles for funding. In the long run neutron bombardment is very likely to lose out because of costs alone.

Tim Meyer wrote:
Besides, I earned my masters in chemistry (1987). You? I'm talking a promising chemical method for high-depletion of lithium for LFTR. And who are you to challenge that? What's your problem?

I am a part time computer engineer and a full time post-bachelor student, studying large data analysis. When discussing chemistry you obviously win out. I studied enough chemistry and physics to understand many of the things discussed here, and obviously my ignorance shows. Neutron bombardment looks like a low risk, though high cost, solution. Fractional distillation looks promising too. I can see why centrifuges is an unlikely solution but may prove feasible of done right. Every method proposed here has it's problems which is why this discussion has gone on as long as it has. Don't think I'm stopping you from doing anything.

You mentioned Dr. Stephen Boyd before which reminded me of something he's said. Dr. Boyd sees LFTR and technologies like it as something that can potentially drive chemical processes, even if it does not produce a single watt-hour of electricity. Perhaps this is where some of the problem lies, people are so focused on using LFTR to drive a turbine that they've blinded themselves to other possible uses. These alternative uses may solve some of the problems. A possible example, if we use a LFTR to power a heavy water production plant then the issues of tritium production may just disappear. The production of D2O and T2O is not hampered by some tritium in the product since that tritium *IS* the product.

Again my ignorance may be showing since my example of an alternate use for LFTR may not be a good one. It just appears to me that the desire for high purity lithium isn't just about preventing Li-6 from poisoning the chain reaction but also to avoid the production of tritium. If the tritium problem can be solved then perhaps a compromise on the purity of the lithium can be made to lower the costs, which is one case where neutron bombardment comes in.

_________________
Disclaimer: I am an engineer but not a nuclear engineer, mechanical engineer, chemical engineer, or industrial engineer. My education included electrical, computer, and software engineering.


Top
 Profile  
 
PostPosted: Jun 11, 2016 11:19 am 
Offline
User avatar

Joined: Dec 22, 2015 8:40 pm
Posts: 359
Location: Florida
Kurt, do you think this forum is dead? A few people post here. It used to be more active. When the experienced engineers here post in their language, it's free education. I'm SO glad I paid off my student debt in the 90s. I hated having to owe.

I'm curious to know also, please, if you have or are you going to watch the 2-hour film Gordon McDowell made posted on YouTube "NASA"- Thorium Remix 2016 May 20. I hope you do. If and when, I hope you post your views to:

"NASA" - THORIUM REMIX 2016

and this time I promise to not be such a moron if you post and and your assessment is dissonant in any way.

Thanks, Kurt, to you and others for participating in the one item of what seems to be an Achilles heel in all this molten salt talk.

_________________
"Those who say it can’t be done are usually interrupted by others doing it."

—James Arthur Baldwin, American novelist, essayist, playwright, poet, and social critic


Top
 Profile  
 
PostPosted: Jun 18, 2016 6:46 pm 
Offline

Joined: Nov 14, 2013 7:47 pm
Posts: 574
Location: Iowa, USA
Tim Meyer wrote:
Kurt, do you think this forum is dead?

I do not but I am left with the impression that it is not as active as it used to be. I don't know if this is because of an actual drop in participation or my own limited time to comment.

Tim Meyer wrote:
I'm curious to know also, please, if you have or are you going to watch the 2-hour film Gordon McDowell made posted on YouTube "NASA"- Thorium Remix 2016 May 20. I hope you do. If and when, I hope you post your views to:

"NASA" - THORIUM REMIX 2016


I did see the video and I left a (rather lengthy) comment on the thread you have linked to.

I would also like to clarify my stance on how the problems of the cost and rarity of high purity heavy lithium may be addressed. After reading on how people envision a LFTR might be designed I see a "1.5 fluid" design as having many merits to address this problem. One such design would be graphite moderated, much like a solid fuel reactor, with the thorium and U-233 dissolved in a molten salt. This salt may have heavy lithium to moderate the neutrons and provide a highly fluid salt, or have a different chemistry lacking lithium.

I envision this 1.5 fluid reactor having a blanket salt consisting of pure FLiBe or FLiBe with some thorium salts. As this blanket would be for cooling, and not take part in sustaining the reaction, natural lithium can be used. The neutron absorbing nature of the light lithium in this case should be considered beneficial since it reduces neutron damage to the power plant structure.

As the heavy lithium accumulates in the blanket salt it can be removed for sale and natural lithium put in its place to restore its neutron shielding capability. If thorium also exists in the blanket salt then the protactinium that is produced can be removed and allowed to decay to uranium in a storage tank, with the resulting uranium put into the fuel salt to make up for what is consumed.

I understand that what I propose will mean that tritium will be produced in the blanket salt. There are a number of ways to address this, many of which I do not understand completely. I also understand that tritium production is unavoidable, even with high purity heavy lithium. It seems to me then the problem is one of economics, primarily the cost of falling within regulatory limits of tritium being released into the environment. In that case one might come to question the validity of the limits on tritium release and the linear no threshold models on which those limits are based.

_________________
Disclaimer: I am an engineer but not a nuclear engineer, mechanical engineer, chemical engineer, or industrial engineer. My education included electrical, computer, and software engineering.


Top
 Profile  
 
PostPosted: Jun 21, 2016 11:00 am 
Offline
User avatar

Joined: Dec 22, 2015 8:40 pm
Posts: 359
Location: Florida
Kurt, are you sure on your description of how the breeding blanket works? I thought that neutron economy in that region must be very carefully tuned to optimize formation of protactinium. So any neutron parasites would be expressly avoided in the blanket, correct? Having the highly poisonous 6Li there in abundance as far as I know is not desirable.

Disclaimer: Kurt, I feel a little like you as you've mentioned about yourself. I'm not a nuclear engineer nor will I ever be in all likelihood. Maybe that's a goal for you on the computer modeling and simulation end that is needed for this work. When I first began following the Flibe Energy design in 2014, I became enthralled. At the policy level, it seemed to me that fluid fueled nuclear designs more than deserve a chance to demonstrate their performance characteristics and especially with thorium fuel.

But I guess we citizens have to learn the basics to argue in favor of public efforts to realize the potential advantages of this needed energy technology.

_________________
"Those who say it can’t be done are usually interrupted by others doing it."

—James Arthur Baldwin, American novelist, essayist, playwright, poet, and social critic


Top
 Profile  
 
PostPosted: Jun 21, 2016 12:47 pm 
Offline

Joined: Nov 14, 2013 7:47 pm
Posts: 574
Location: Iowa, USA
Tim Meyer wrote:
Kurt, are you sure on your description of how the breeding blanket works?


I understand how my descriptions can be confusing since I'm bouncing back and forth between using the blanket as a breeder and as purely a coolant/shield salt.

In one case the blanket would be for shielding and cooling. I propose this as I see this as a means to take advantage of the thermal and chemical properties of FLiBe salts in a way that the cheap and plentiful natural lithium would not interfere with the reaction in the core. This also avoids the need to use expensive materials like graphite to separate the salts since the goal is not to conserve those neutrons for breeding but to merely prevent them from leaving the core.

I also proposed the possibility of putting some thorium in the blanket/shield/cooling salt since if by chance there is a capture of a neutron by a thorium then there is some breeding for "free". Thorium in the blanket salt would compromise some of the excellent properties of the FLiBe salt but if this can be tolerated then it makes sense to me to add the thorium to gain that small additional breeding capacity.

An additional advantage that I do not believe I mentioned is that in the case of the blanket salt leaking into and contaminating the fuel salt the contamination could be offset somewhat by the thorium. I don't know if this is enough to matter since the light lithium in the coolant would be a terrible contaminant.

Another option that came to me is using a marker salt of some sort in the blanket to give indication of the location and severity of cross leakage. Perhaps a zirconium salt.

If the core salt consists of FLiBe and fuel salts, and the blanket contains FLiBe with a zirconium marker, then sensors in the core that can detect the marker will give indication of leakage. The blanket and core salts will both contain heavy and light lithium in vastly different proportions, which could make detecting cross leakage difficult since determining the proportion of heavy and light lithium accurately sounds to me to be inherently difficult. If the blanket salt contains zirconium and the core does not, and the core contains thorium and the blanket does not, then looking for thorium and zirconium in the wrong places can show how much leakage there is and in which direction.

A big problem of two fluid designs is keeping the two fluid separate and still allowing enough neutrons to pass from the core to the blanket. One solution is to use a delicate and expensive graphite barrier. After thinking this through I am beginning to wonder if there is a way to compromise on this by having a 1.5 fluid design with a non-graphite barrier. There would be lost neutrons in the barrier wall but it would not have to be made of the problematic graphite. This would mean that the blanket could not use natural lithium since breeding would have to be optimized. If the light lithium is allowed to transmute to heavy lithium before breeding could occur then we get into a regulatory problem where the chemistry, neutronics, and so forth change with time, and government regulators are unlikely to sign off on a reactor that will have its method of operation change like that. The reactor would start as a burner but slowly shift to a breeder over its operational life.

_________________
Disclaimer: I am an engineer but not a nuclear engineer, mechanical engineer, chemical engineer, or industrial engineer. My education included electrical, computer, and software engineering.


Top
 Profile  
 
PostPosted: Jun 21, 2016 1:08 pm 
Offline

Joined: Jun 19, 2013 11:49 am
Posts: 1552
Wouldn't fission Zirconium cause issues with that proposal?


Top
 Profile  
 
PostPosted: Jun 21, 2016 1:45 pm 
Offline

Joined: Nov 14, 2013 7:47 pm
Posts: 574
Location: Iowa, USA
E Ireland wrote:
Wouldn't fission Zirconium cause issues with that proposal?


Yes, I believe it would. I proposed zirconium salts because they have been shown as a viable additive in MSRE, and having certain beneficial chemical, neutronic, and physical properties. The production of zirconium from fission did not occur to me.

I would hope the rest of my basic concept remains valid. Use cheap natural lithium in the blanket/shield/coolant salt. Use the expensive high purity heavy lithium in the core salt. Then use a marker salt to assist in detecting cross contamination.

_________________
Disclaimer: I am an engineer but not a nuclear engineer, mechanical engineer, chemical engineer, or industrial engineer. My education included electrical, computer, and software engineering.


Top
 Profile  
 
PostPosted: Jun 23, 2016 3:36 pm 
Offline
User avatar

Joined: Oct 06, 2010 9:12 pm
Posts: 138
Location: Cleveland, OH
As soon as you start using 6Li, even in the blanket, you will lower your breeding ratio by a lot. Which may be fine depending on your design goal(s). I could be wrong, but I think the impact of the 6Li in the blanket would be so great that you would have little to gain by having high purity 7Li in the fuel salt, especially since many designs have a greater volume of blanket salt in-core than fuel salt.


Top
 Profile  
 
PostPosted: Jun 24, 2016 2:35 pm 
Offline

Joined: Jun 15, 2016 8:17 am
Posts: 9
As I am new to this forum, and also a novice in the arena of LFTR, molten salt chemistry and the Thorium / FLIBE fueling and U233 breeding processes, I would like to pose a question or two, with a couple of amateur observations. I will apologize in advance if my questions / observations sound like something out of a "LFTR For Dummies" book..

First, for the quantities and concentrations needed of the U233 vice the molten FLIBE, what might be the statistics of the dilution reactivity of, say, 1% 6Li/99% 7Li against U233? For the 6Li, as it is also mixed in the salt with BeF2, the neutron capture likelihood should also lessen. I would think that if the U233 is also at 1% of the salt, then the (relative) likelihood of neutron capture could be 50% (if 6Li and U233 have a similar cross section). Of course, this disregards other very likely reactors, such as the Thorium and other capture-prone isotopes in the mix. With a higher concentration ratio of U233, I would expect the 6Li capture probability to go down accordingly, and the U233 fission likelihood to increase proportionally. A break-even concentration should be in there somewhere, which would allow the reactor to progress when the concentrations exceed the break-even point. Is there a difference between 6Li effects in a breeding blanket vice the main fission reactor? I would suppose it depends mainly on the end design and operational constraints.

With the reactivity of 6Li producing Tritium, would the now-free Fluorine from the (former) 6LiF capture one of the Tritium atoms yielding TF gas, which could be (relatively easily) captured and removed / sequestered along with remaining T2 unreacted gas? Boosting 7Li to, say, 99% vice 99.995% should cost a lot less and make the economics a better fit.

Is there a ready market for Tritium in industry, medicine, or other users?

Are there any 'Hydrogen/Tritium scavengers' in chemistry that could be added to the FLIBE salt to mitigate/sequester the gaseous Tritium without undue negative effects on the hot reactor fluid?

Could sequestered ' solid state ' forms of Tritium (various metal hydrides perhaps?) be used to safely power an array of RTGs to produce salable electricity for a few years as the Tritium decays?

As 7Li is slightly heavier than 6Li, is there any adverse effect on salt viscosity or flow properties at the LFTR temperatures?

Thank you in advance for reading through my ramble. I hope the above actually makes sense to someone more knowledgeable than me.


Top
 Profile  
 
PostPosted: Jun 24, 2016 10:16 pm 
Offline

Joined: Nov 14, 2013 7:47 pm
Posts: 574
Location: Iowa, USA
Mikeaustria wrote:
First, for the quantities and concentrations needed of the U233 vice the molten FLIBE, what might be the statistics of the dilution reactivity of, say, 1% 6Li/99% 7Li against U233?


I believe many of your questions can be answered by reading this blog entry from our host:
http://energyfromthorium.com/2006/07/11 ... from-them/

I'll try to summarize. The apparent "size" of a nucleus to a moving neutron is measured in a unit called a "barn". Lithium-6 has a cross section of about 940 barns, and thorium-232 has a cross section of about 7 barns. This means a neutron is many times more likely to be captured by Li-6 in the event of a collision than thorium. I'm not quite sure how the math works out on calculating the probabilities exactly but the ratio of Li-6 to Li-7 must be very very small or there will not be enough neutrons to sustain a reaction. Since the number of neutrons produced from a U-233 fission is less than 2.5 that means there are not many neutrons to spare. One of the neutrons produced replaces the one consumed in the fission, one is needed to breed more fuel, and what ever is left is the margin that can be spared to Li-6 capture, loss to the environment, or whatever. As this margin is very small the chemical composition of the fuel must be precise.

Mikeaustria wrote:
Boosting 7Li to, say, 99% vice 99.995% should cost a lot less and make the economics a better fit.

99% purity simply will not work. That is why we are discussing the economy of purity that is 99.99% pure vs. 99.99999% pure. The number of neutrons produced in a fission differs on the element being fissioned. U-233 produces less than 2.5 neutrons per fission but U-235 produces more. I'm not sure how many more but I do not believe it is greater than 3. This means that one can consume some small amount of impurity of LI-6 by starting the LFTR reactor with U-235 instead of U-233. This may make the economics more favorable but at the cost of obtaining high purity U-235 instead of high purity Li-6. Much of the cost of high purity U-235 is because of the regulation of high purity U-235. The differing regulation of U-235 and U-233 is because U-235 is useful for producing weapons while U-233 is not.

Mikeaustria wrote:
Is there a ready market for Tritium in industry, medicine, or other users?

Yes, tritium is used in making nuclear weapons which is why it is a highly regulated material. Tritium is used in small quantities for things like glow in the dark paint for things like watches, the tritium is mixed with a fluorescent material in the paint. I do not believe it has much use in medicine as it is a radiation hazard to anything living.

Mikeaustria wrote:
Could sequestered ' solid state ' forms of Tritium (various metal hydrides perhaps?) be used to safely power an array of RTGs to produce salable electricity for a few years as the Tritium decays?

I'm certain that using tritium in RTGs is technically feasible but there are much better materials for RTGs. Explaining all the pros and cons of tritium and other RTG materials would be a lengthy explanation. Essentially since we have access to much better RTG material the usefulness of tritium in RTGs is zero.

Mikeaustria wrote:
As 7Li is slightly heavier than 6Li, is there any adverse effect on salt viscosity or flow properties at the LFTR temperatures?

Not really. So much of the mass of the salt would be in the uranium and/or thorium that any reductions in mass from using Li-6 vs. Li7 would be lost in a rounding error.

_________________
Disclaimer: I am an engineer but not a nuclear engineer, mechanical engineer, chemical engineer, or industrial engineer. My education included electrical, computer, and software engineering.


Top
 Profile  
 
PostPosted: Jun 24, 2016 10:44 pm 
Offline

Joined: Nov 14, 2013 7:47 pm
Posts: 574
Location: Iowa, USA
Jim L. wrote:
As soon as you start using 6Li, even in the blanket, you will lower your breeding ratio by a lot. Which may be fine depending on your design goal(s). I could be wrong, but I think the impact of the 6Li in the blanket would be so great that you would have little to gain by having high purity 7Li in the fuel salt, especially since many designs have a greater volume of blanket salt in-core than fuel salt.


Can a barrier between the two salts be constructed in a way that minimizes the neutron loss enough to make my proposal feasible? As some neutrons will undoubtedly enter the blanket this loss, as you point out, does need to be considered. I have no doubt in that.

Again my ignorance is showing. I was under the assumption that once a neutron left the core that it would not return. Upon some further research I understand that some of those neutrons would be reflected back into the core by elements like Li-7 where it would be captured by elements like Li-6. If the blanket cannot serve as a neutron reflector then perhaps a reflective layer can be placed on the barrier that separates the two salts.

_________________
Disclaimer: I am an engineer but not a nuclear engineer, mechanical engineer, chemical engineer, or industrial engineer. My education included electrical, computer, and software engineering.


Top
 Profile  
 
PostPosted: Jun 25, 2016 11:43 am 
Offline
User avatar

Joined: Dec 22, 2015 8:40 pm
Posts: 359
Location: Florida
Kurt, what did Dr. Weinberg and his cadre of scientists, nuclear engineers, metallurgists, and technicians miss at ORNL during the MSBR program? Their lithium salt was highly depleted and they didn't use neutrons for depletion. If your proposal is sound, wouldn't the ORNL group had used it? The nuclear engineers on this forum could answer this question straight away.

_________________
"Those who say it can’t be done are usually interrupted by others doing it."

—James Arthur Baldwin, American novelist, essayist, playwright, poet, and social critic


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 47 posts ]  Go to page Previous  1, 2, 3, 4  Next

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group