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PostPosted: Sep 22, 2008 7:44 am 
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The book of Tom Blees (Prescription for the Planet) is now available for purchase on amazon. It is currently listed at half-price (12.5 dollars). So if you intend to buy the book, do it quickly :)

Blees is an active proponent of the IFR (integral fast reactor) of the Argonne National Labs. He considers breeder reactors to be the prescription for energy problems. Along with IFR, Blees also advocates Boron fuel cells for transport, and biomass incineration for producing gasolene and plastics.

We discussed Tom Blees on an earlier thread. His book is referred to by a pro-nuclear article by Marc Lynas in the New Statesman. Blees contributed a lot in the discussion that followed.


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PostPosted: Sep 22, 2008 8:08 am 
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First, the book is no longer on half-price :( It disappeared even before I placed my order. Too late.

Second, the technology Blees advocates is not biomass incineration, but plasma gasification.


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PostPosted: Dec 04, 2008 8:08 pm 
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Now that we've got Tom here on the forum, I wanted to go ahead and start a thread about his new book "Prescription for the Planet". Here's a link to the book on Amazon:

Amazon: Prescription for the Planet

Image

Here's a description for the book:

Quote:
An end to greenhouse gas emissions, a global framework to control nuclear proliferation, a preemptive remedy to looming water wars, and unlimited energy worldwide are just a few of the concrete solutions offered up in Tom Blees's brilliant and timely Prescription for the Planet. Everyone is worried about global warming, energy wars, resource depletion, and air pollution. But nobody has yet come up with a real plan to resolve these problems that can actually work-until now. Prescription for the Planet proposes a workable blueprint to virtually eliminate greenhouse gas emissions by the middle of this century and solve a host of other seemingly intractable global problems.

Solving our planet's most pressing dilemmas requires more than simply setting goals. We need a roadmap to reach them. Technologies that work fine on a small scale cannot necessarily be ramped up to global size. Worldwide environmental and social problems require a bold vision for the future that includes feasible planet-wide solutions with all the details. Prescription for the Planet explains how a trio of little-known yet profoundly revolutionary technologies, coupled with their judicious use in an atmosphere of global cooperation, can be the springboard that carries humanity to an era beyond scarcity. And with competition for previously scarce resources no longer an issue, the main incentives for warfare will be eliminated.

Explaining not only the means to solve our most pressing problems but how those solutions can painlessly lead to improving the standard of living of everyone on the planet, Blees's lucid and provocatively written Prescription for the Planet has arrived not a moment too soon. There is something here for everyone, be they a policymaker, environmental activist, or any concerned citizen hoping for a better future.


Here's a link to Tom's website for the book:

Prescription for the Planet

PftP argues for a restart of the Argonne/INEL Integral Fast Reactor program to tackle planetary energy needs. I'm very glad to welcome Tom on here, who has been a true friend to those of us who want to see advanced nuclear energy developed worldwide.


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PostPosted: Dec 08, 2008 12:50 am 
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I`ve read about half the book so far, great work Tom. Perhaps a bit on the over enthusiastic side for IFR but the book reveals lots of insider information that gives one a much more complete view of the fast breeder saga.

One point that I really must protest though is in regards to the ability of the IFR system to avoid transuranic elements going to waste. I am sure Tom was lead to believe this and quite likely the people who informed him thought it true as well but it is a surprisingly little known fact that the IFR pryoprocessing system does send a great deal of transuranic elements to waste (I suppose a "great deal" is a relative term).

A fast breeder has to process a great deal of transuranics (mainly plutonium) every year and their early goal was to be sure to not have more than 0.1% ending up as wastes. The fact is they were never able to do much better than 1% or 2% going out as wastes. Since they have to process such a great deal of plutonium that means a lot going to wastes, not as much as a LWR once through cycle but probably about a tenth of that (perhaps around 20kg per GWe year versus 250 kg for LWR versus 20 to 50 grams for LFTR). From the expert I spoke with, they think they might be able to do 0.5% but he goes by the assumption of 1%. He told me that right after a conference talk in which he gave the standard IFR line that NO ACTINIDES go to waste.

When I gave a talk recently one of the most respected nuclear engineers in Canada politely corrected my about a slide which assumed only 0.1% going to waste for IFR (and which I mentioned it could be more like 0.5%). He worked at Argonne on fast breeders for years and when he double checked for me he got the same response, I think he was more surprised than anyone. I`ve posted this slide many times but let me do so again. It assumes 0.1% loss for a fast breeder (say with PUREX) but pyroprocessing seems to be much more. Perhaps it could be argued that if they spent more money they could drop the 0.5% waste figure but the fact is that is what is expected.

The red line is for a solid fueled fast breeder with 0.1% of transuranics lost during processing. The IFR would unfortunately be at least 5 times that. The green and blue lines are for molten salt reactors with 0.1% lost during reprocessing.

Image

Anyhow, I just wanted to stress that point again. Otherwise in the book from what I`ve read so far I would completely agree how good an idea plasma processing of garbage is (we here in Ottawa have one of the leading companies building a pilot plant). Regarding boron as a energy carrier, I`d also agree it is a leading candidate but I would not think trying to burn it in a pure oxygen environment has much hope of success. It is far simpler to just bring along some water and use the boron to produce hydrogen on demand. You can then burn that in a slightly modified engine or fuel cell.

http://www.newscientist.com/article/mg19125621.200


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PostPosted: Dec 08, 2008 2:42 am 
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It has been difficult to understand where people are with recycling. PUREX seems to achieve around 99.5% extraction for U and Pu but nothing mentioned about Am or Cm (and so I'm thinking nothing extracted). I have seen liquid metal reduction used as a followup process on the high level liquid wastes where the 0.5% leaked to. There they get another 99% (just a tiny lab experiment not an industrial flow). I've also seen references to older papers targetting 4e-6. Pretty wild discrepencies from 1e-2 to 4e-6.

In LFTR, we need to treat 233U leakage as being just as nasty as 239Pu. Fortunately, it appears U is easier to extract than Pu. But the whole issue of recycling leakage is very murky.


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PostPosted: Dec 08, 2008 7:18 am 
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@David

I don't usually trust the material in new-scientist. This magazine often posts flashy and unsubstantiated research results.Case in point : this study about how heat we emit is an important factor in the radiative forcing of the earth's temperature. This article builds a strong case against nuclear power, which is quite unheard of till recent times.

The article about using Boron along with water to produce Hydrogen seems similar to me. The problem with this approach is that the energy density gets too low, because of the added weight of water. Is this technology worth this extra weight ? What positives does it exhibit, as compared to the pure-oxygen combustion of GRL Cowan ?

By the way, the criticism that you made against IFR is very interesting. I am not a nuclear scientist and I cannot comment on this issue. Why is it difficult to separate unburned actinides during the pyroprocessing step, from other fission products ? If they can be separated, they can be put back into the fuel assemblies right ? Even if they don't get burned up immediately, they will eventually be used up and none of the actinides would leave the reactor. ..


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PostPosted: Dec 08, 2008 7:33 am 
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AFAIK pyroprocessing uses full actinide recycle, unlike PUREX and most of other aqueous processes.

Indeed - http://www.anl.gov/Media_Center/Frontie ... /d1ee.html
Quote:
Pyroprocessing is a nuclear-fuel treatment and recycling technology developed at Argonne. It is a multi-step process that removes actinides — uranium, plutonium and other transuranic elements that take hundreds of thousands of years to decay — from used nuclear fuel and recycles them back into new fuel.


The other issue is the purity of the waste stream, which however will be addressed by continuing technology improvement during future development, and can be improved by multistage reprocessing of the wastes: 1st pass to recover U+TRU fuels, 2nd pass to extract separate high purity fission products, 3rd pass to recover remaining TRU from the rest, for the IFR-like cycle.

Therefore the waste stream can be claimed to be FPs only, with a small print concerning purity.

PS - I went on a shopping spree at Amazon and bought Tom's book among others, yay sweet postdoc salary (compared to a grad student stipend which was about what i payed in rent :) )


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PostPosted: Dec 08, 2008 11:51 am 
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Lars,

Good point about PUREX and the minor actinide Am and Cm, I am actually not sure how they handle those. PUREX is able to capture a very high percentage of Pu (I've seen 99.99% quoted) but if they do skip Am and Cm for a fast breeder reprocessing then the situation isn't all that good in terms of radiotoxicity (Am and Cm would be significant in a fast breeder cycle).

I agree that even for LFTR we need to get better facts. The most likely process will be to only use liquid bismuth extraction to remove Pu, Am and Cm. The efficiency is not well known but the big advantage we have is that we are only trying to reprocess a few kg of Pu,Cm and Am a GWe year instead of literally tonnes in a fast breeder.


Vakibs,

The boron to hydrogen doesn't sound like much to carry. 18 kg of boron plus 45 litres of water to equal the energy of 40 litres of gas.

As to how plutonium is lost in the pyroprocess and if it could be somehow recovered if we spent more money, I am not too sure of that. The papers I've read were not too clear and as you can probably guess, when people publish about IFR they are not going to focus too deeply on its shortcomings.

Ondrejch,

Yes, the standard line about IFR pyroprocessing is that ALL actinides are recycled back into the reactor. However the truth is they haven't been able to do better than about 1% going to waste. Again I am not sure the details but if this loss ends up mixed with large masses of processing chemical or diffuses into cathodes etc it might be extremely expensive to try to simply do more processing to lower these losses. As I said, Argonne's initial goal was to have much less than 0.1% going to waste and they only were able to do 1% or so, I would be certain they tried quite hard to do better so it might just not really be possible given the system. If anyone from Argonne wants to chime in with specific details please do so.

David L.


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PostPosted: Dec 08, 2008 12:10 pm 
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David wrote:
Yes, the standard line about IFR pyroprocessing is that ALL actinides are recycled back into the reactor. However the truth is they haven't been able to do better than about 1% going to waste. Again I am not sure the details but if this loss ends up mixed with large masses of processing chemical or diffuses into cathodes etc it might be extremely expensive to try to simply do more processing to lower these losses. As I said, Argonne's initial goal was to have much less than 0.1% going to waste and they only were able to do 1% or so, I would be certain they tried quite hard to do better so it might just not really be possible given the system. If anyone from Argonne wants to chime in with specific details please do so.


Hi David,

agreed, however, imagine the following path :
1) pyroprocessing the stuff IFR-like
2) take IFR-waste, isolate&purify (and sell) all the usable FPs by say vacuum distillation (was not considered then). it reduces waste volume further
3) run UREX+ or alike on a concentrated mess left behind 1) 2) to extract left over U+TRUs
4) vitrify the rest

Now these 4 steps can be done, however it is important that we do not need all of them right now to achieve goals of IFR. After say 50 years of significant growth of IFR-like power stations, step 2 may make sense. After 100 years steps 3&4 may start to make sense.

Is there a need to reprocess everything down to the last atom now? No! We need to show a believable path, which does solve the problems of contemporary LWRs (waste, proliferation, uranium supply, cost, Yucca etc) - all these are addressed, and one must not get distracted by cosmetic details, esp. when a truthful answer exists, albeit not formulated in straight-forward way (as of yet).

Do we know the purity of HyperUREX++ process which will be tested in 2108? We do not, however we already now have a process with 10^-4 purity ...

There is nothing 100.0% in real life chemistry, but people dont know that, and we have to find our way around it. "No TRU waste" with small print is much more honest than contemporary greenwashing such as "Windmills are renewable", "Never heard about Si Cl4", or "CdTe is perfectly cool", which apparently bothers none but a few geeks herein :)


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PostPosted: Dec 09, 2008 12:41 am 
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From Yoon Chang of Argonne:

In the current PUREX type aqueous reprocessing, the uranium and plutonium products are very clean (no fission product contamination). The decontamination factor is known to be of the order of 0.000001. This refers to fission product removal and does not refer to the product recovery efficiency. My guess is that the plutonium recovery factor is of the order of 99% (meaning it is not 99.9% nor 90%). On the order of 1% plutonium and all other minor actinides (Np, Am,Cm, etc.) go to the waste stream.

In pyroprocessing, there are two types of cathodes. One cathode collects uranium, and the other a combination of plutonium and all minor actinides. The cathode deposit efficiency can be poor, namely not all uranium and actinides are deposited to cathodes when an elctrorefiner run is made. Maybe you get 90% deposited or even less. However, what is remaining in the electrorefiner becomes a part of the feed, along with additional spent fuel loaded in the anode, for the next run. The material is not lost. So, it is not the recovery efficiency, like in PUREX reprocessing, that matters. What is important is what goes out with the wastes. The uranium cathode products are distilled to remove the adhering salts. The resulting uranium ingot is then consolidated at very high temperature. In this process, some dross is formed as a result of uranium interacting with some oxide-coated graphite crucible. If the dross is thrown away, the uranium loss could be of the order of 5%. But this uranium has very low economic value and no radiological toxicity, and hence no harm done to discard it. The actinide cathode can be treated similarly, but care should be taken to minimize actinide loss to waste stream. This is simply an economic tradeoff. If the loss factor is unacceptable, then you add one more treatment step to recover more actinides. You can set up a target of 0.1% loss or any appropriate limit and the process can be designed to achieve it. Any experiments done to date may or may not meet this target in one run, but this does not represent the ultimate commercial operation. What I discussed here is just principles involved and I don't know of any particular experimental results to contradict them.


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PostPosted: Dec 09, 2008 12:56 am 
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For an LFTR system the uranium is not innocuous - the 233U is similar to plutonium and we need to be very careful to not ship it into the waste stream.

Our required fuel cleanliness is dramatically less than for solid fuel.

How far can we go with the refining?
Suppose we have a mixture of 10 tonnes fission products, 80kg U, 2kg Np, 26 kg Pu, 10kg Am, and 10kg Cm. Can one separate so well that the waste has only 2-3 kg of (U+TRUs) while the returned fuel has all the (U+TRUs) + <1 tonne fission products?


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PostPosted: Dec 09, 2008 12:25 pm 
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Tom Blees wrote:
From Yoon Chang of Argonne:

In the current PUREX type aqueous reprocessing, the uranium and plutonium products are very clean (no fission product contamination). The decontamination factor is known to be of the order of 0.000001. This refers to fission product removal and does not refer to the product recovery efficiency. My guess is that the plutonium recovery factor is of the order of 99% (meaning it is not 99.9% nor 90%). On the order of 1% plutonium and all other minor actinides (Np, Am,Cm, etc.) go to the waste stream.

In pyroprocessing, there are two types of cathodes. One cathode collects uranium, and the other a combination of plutonium and all minor actinides. The cathode deposit efficiency can be poor, namely not all uranium and actinides are deposited to cathodes when an elctrorefiner run is made. Maybe you get 90% deposited or even less. However, what is remaining in the electrorefiner becomes a part of the feed, along with additional spent fuel loaded in the anode, for the next run. The material is not lost. So, it is not the recovery efficiency, like in PUREX reprocessing, that matters. What is important is what goes out with the wastes. The uranium cathode products are distilled to remove the adhering salts. The resulting uranium ingot is then consolidated at very high temperature. In this process, some dross is formed as a result of uranium interacting with some oxide-coated graphite crucible. If the dross is thrown away, the uranium loss could be of the order of 5%. But this uranium has very low economic value and no radiological toxicity, and hence no harm done to discard it. The actinide cathode can be treated similarly, but care should be taken to minimize actinide loss to waste stream. This is simply an economic tradeoff. If the loss factor is unacceptable, then you add one more treatment step to recover more actinides. You can set up a target of 0.1% loss or any appropriate limit and the process can be designed to achieve it. Any experiments done to date may or may not meet this target in one run, but this does not represent the ultimate commercial operation. What I discussed here is just principles involved and I don't know of any particular experimental results to contradict them.



Thanks for the info Tom, if that is true about being able to run the process multiple times to lower the losses then that is good news. I was wondering where the transuranics were leaving the system. I had heard that they only thought they could get down to 0.5% but if they can get down well below 0.1% by spending a lot more money on the reprocessing then good. Even at 0.1% the radiotoxicity at the 500 year mark is still well above the quote often used about "as low as uranium ore", they'd need to process even further for that claim. I just think it hurts everyone promoting nuclear when claims have "fine print" built into them or are otherwise exaggerating things. I know the anti-nuclear folks do it all the time.

About PUREX, the quote I've heard is that it can indeed also be very good for not sending much Pu to waste. Page 7 of the second paper below mentions 99.99% of Pu recovered. Otherwise of course it is very bad for producing very clean Pu (proliferation concerns) and large volumes of fission product ladened chemical wastes.

David L.


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PostPosted: Dec 10, 2008 2:19 am 
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In regard to the idea of processing the waste multiple times: It may seem like that would be a costly process, but think about it this way: If you were running PRISM reactors totaling about 2-2.5 GW, the amount of spent fuel you'd have to process daily to keep it running would be about a gallon (solid, of course). So it's a very small-scale operation. Since you'd have the recycling facility right on site, it would be a small matter—and very inexpensive since it would be all electric and remote controlled—to run the waste through as many times as you'd wish. I should think the system could be quite automated. So the cost of making the eventual waste virtually actinide-free looks thoroughly doable, at very little cost whatsoever.


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PostPosted: Dec 10, 2008 12:27 pm 
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Tom Blees wrote:
In regard to the idea of processing the waste multiple times: It may seem like that would be a costly process, but think about it this way: If you were running PRISM reactors totaling about 2-2.5 GW, the amount of spent fuel you'd have to process daily to keep it running would be about a gallon (solid, of course). So it's a very small-scale operation. Since you'd have the recycling facility right on site, it would be a small matter—and very inexpensive since it would be all electric and remote controlled—to run the waste through as many times as you'd wish. I should think the system could be quite automated. So the cost of making the eventual waste virtually actinide-free looks thoroughly doable, at very little cost whatsoever.


Lets hope so but I don't think it as rosy a picture as that. Argonne and INL spent a very long time on this process with the stated goal of getting losses below 0.1% . The fact that they have settled on a system that is only within a factor of 10 of this doesn't leave me to believe that getting below 0.1% will be at very little cost. I don't know enough about the process to say more than that though.

David L.


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PostPosted: Dec 12, 2008 3:41 am 
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Yoon Chang explained in the post above how it's done. I've worked with him for years and I can tell you he is not one to make idle claims. If he says we can adjust the system to reach 0.1% or less, I believe him. If anybody would know it would be him.


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