Reprocessing of Spent Nuclear Fuel

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I hear a lot of talk about the law from teh 70's passed by Congress that forbade the reprocessing of commercial SNF. In my Radioactive Waste Management class today, the professor (who is a CHP/PE who specializes in waste management) said it was actually Carter, not Congress (which means, I assume, it was an Excutive Order), but Reagan lifted the ban later on. There are, of course treaties such as the Non-Proliferation Treaty and perhaps others that aim to curtial the plutonium accessible for possible terrorism, etc.) He was pretty sure that reprocessing was allowable even by treaty as long as the site allowed independent inspection by the IAEA.

My question is whether this is still a law that is active, if so, what is the name of this law/act, and the specifics of the law (links are helpful here). I ask because for another class, we are doing research into the molten salt reactors. For my group, we are considering the online reprocessing possibility, including (but not limited to) the legal aspects of online reprocessing, so i need to look up this info. I can't seem to find any evidence for such a law on web searches, but since it has been mentioned numerous times, I need to find out the facts.
 

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  • #2
Astronuc
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There are references to Jimmy Carter's (April) 1977 executive order in which he apparently suspended reprocessing of SNF, but after some research, I cannot find such an EO. There was only one in April of 1977 - EO 11982 - Committee on Selection of the Director of the Federal Bureau of Investigation.

Perhaps Carter announced in April the intent to suspend reprocessing of spent nuclear fuel (SNF).

I believe the suspension of reprocessing was in the Department of Energy Organization Act, PL 95-91, signed 8/4/77, which may be confused with Reorganization Act of 1977, PL 95-17, signed 4/6/77, the latter being reorganization of the Executive Office of the President.


http://www.stanfordreview.org/Archive/Volume_XXXIII/Issue_4/Opinions/Opinions3.shtml [Broken]

Nuclear Industry Supports Reprocessing Research But Foresees Long Road to Implementation

WASHINGTON—The nuclear energy industry supports continued research into more efficient and proliferation-resistant technologies to reprocess used nuclear fuel. But the industry sees significant challenges – economic and otherwise – to overcome before reprocessing can be developed in the United States, the Nuclear Energy Institute’s chief nuclear officer, Marvin Fertel, told a congressional panel today.

. . . .

He noted that reprocessing has not been employed in the United States for more than 20 years. The technology was banned by President Carter due to proliferation concerns. President Reagan lifted the ban, and President Clinton later reinstituted it.

The Separations Technology and Transmutation Systems (STATS) Report: Implications for Nuclear Power Growth and Energy Sufficiency
http://www.nationalcenter.org/NPA396.html


http://www.pbs.org/wgbh/pages/frontline/shows/reaction/readings/rossin.html
3. THE CARTER POLICY

On April 7, 1977, President Jimmy Carter announced that the United States would defer indefinitely the reprocessing of spent nuclear reactor fuel. He stated that after extensive examination of the issues, he had reached the conclusion that this action was necessary to reduce the serious threat of nuclear weapons proliferation, and that by setting this example, the U. S. would encourage other nations to follow its lead.

President Carter's Executive Order also announced that the U. S. would sponsor an international examination of alternative fuel cycles, seeking to identify approaches which would allow nuclear power to continue without adding to the risk of nuclear proliferation. More than thirty nations participated over almost three years. But no new magic answer could be found.
 
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  • #3
vanesch
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Carter's policy was a failure in several respects. Carter wanted the US to "show the example" by not using spend fuel reprocessing, with the hope that other nations would follow that example and not reprocess. But that clearly didn't work out as the French and the British have set up a reprocessing plant (Sellafield and La Hague). As such, the idea that if the US doesn't devellop fuel reprocessing, the technology will not be industrially available, failed.

But the second error in Carter's policy was that reprocessing of spend fuel in LWR is by itself not much of a proliferation issue, because the plutonium one gets out of it isn't really weapon-grade quality if the burnup is high. Now, there are discussions of whether it is possible or not to build a badly working weapen anyhow with this plutonium, but as most of this is classified information I guess it is hard to know. It is a bit funny that a nation who had a huge stockpile of weapongrade plutonium for military purposes was being affraid that non-military grade plutonium might somehow be stolen...

In the mean time, the PUREX process is not really a big secret, and everyone who really wants to build a reprocessing plant can do so with enough $$$. The extracted plutonium from PWR spend fuel is probably not good enough to make a good working nuclear weapon, but at least if you extract it, you can control it ; if you leave the spend fuel "as is", anybody can come and mine the plutonium.

So I find it a huge pity that advances in the fuel cycle are being blocked with silly considerations of non-proliferation, based upon the erroneous idea that somehow it is easier for someone to make a nuclear weapon by stealing bad quality plutonium from a country that has reprocessing capabilities and try to make a working weapon out of that (which is way more difficult), than to make weapon-grade plutonium oneself using a good old graphite/natural uranium reactor and some tri-butyl phosphate.

Now maybe I have some misconceptions on the issue, in which case I would like to be enlightened.
 
  • #4
Astronuc
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because the plutonium one gets out of it isn't really weapon-grade quality if the burnup is high. Now, there are discussions of whether it is possible or not to build a badly working weapon anyhow with this plutonium
For high burnup fuel, that would be more or less true, but one could build a weapon with the Pu. The problem however would be the radiation which would injure the workers and damage components, but then some groups don't worry about such matters. It certainly would be much easier to detect.

There are ways to optimize the conversion of U to Pu (239) with low levels of Pu-241 and heavier nuclides, but that's something not to be shared.

Controls on SNM are fairly strict, so proliferation from the US is not the problem. As one indicated, Carter wanted to set an example for other countries to follow, but it was rather misguided, and certainly France, Britain, Russia and Japan have reprocessing capability. India and Pakistan (A. Q. Khan) also have that capability.
 
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  • #5
vanesch
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For high burnup fuel, that would be more or less true, but one could build a weapon with the Pu. The problem however would be the radiation which would injure the workers and damage components, but then some groups don't worry about such matters. It certainly would be much easier to detect.
I think that this is indeed a silly argument: if you set out to build a nuclear weapon, surely you're able to devise some radioprotection! The point is that "polluted" Pu (that means, anything else than Pu-239) needs first of all a much higher mass to build a weapon from, and "pre-ignites" too easily. So the building of the weapon itself is much harder with "bad" Pu than with weapon grade Pu ; I don't even know (and will probably never find out) whether it is feasible or not. As such, for some organization which has the technical ability to do all that, it would be no problem for them to:
1) have radioprotection (or suicide fools who don't mind)
2) make weapon grade plutonium themselves using "standard" techniques, not having to rely on stolen spend fuel.

There are ways to optimize the conversion of U to Pu (239) with low levels of Pu-241 and heavier nuclides, but that's something to be shared.
Sure: a good old graphite reactor with continuous fueling does that very well...
That's how the first weapons were made anyhow.
 
  • #6
Astronuc
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I think that this is indeed a silly argument: if you set out to build a nuclear weapon, surely you're able to devise some radioprotection! The point is that "polluted" Pu (that means, anything else than Pu-239) needs first of all a much higher mass to build a weapon from, and "pre-ignites" too easily. So the building of the weapon itself is much harder with "bad" Pu than with weapon grade Pu ; I don't even know (and will probably never find out) whether it is feasible or not. As such, for some organization which has the technical ability to do all that, it would be no problem for them to:
1) have radioprotection (or suicide fools who don't mind)
2) make weapon grade plutonium themselves using "standard" techniques, not having to rely on stolen spend fuel.
Nuclear weapons are not pure Pu239, but certainly one would wish to minimize the other isotopes.

A weapons designer wishes to minimize mass, which is not an important consideration for some people.

Sure: a good old graphite reactor with continuous fueling does that very well...
That's how the first weapons were made anyhow.
I was thinking in the context of an LWR. A graphite reactor would be quite obvious.
 
  • #7
vanesch
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Nuclear weapons are not pure Pu239, but certainly one would wish to minimize the other isotopes.

A weapons designer wishes to minimize mass, which is not an important consideration for some people.
I don't know much about all this, but it was my understanding that polluted plutonium is difficult, not really because of the extra mass, but rather because the implosion requirements are much more difficult to achieve: you have more absorption and less fission cross section, and you have more spontaneous fission. All this means that the power increase is slower during the implosion, and hence that you pre-ignite much easier.
If you master all this technology, then surely you can master a graphite/natural uranium reactor.

Point is, I find it a silly argument in several Western countries to refrain from having fuel reprocessing in the nuclear power sector simply because of proliferation issues. People (terrorists, a gouvernment, country...) who have decided to make a nuclear weapon will not make use of the fuel cycle in another country to do so. I don't think the North-Coreans tried to steal plutonium from La Hague to make their bombs. India and Pakistan didn't base their (initially forbidden) nuclear weapon program on stolen plutonium.
The main pathways to a nuclear weapon are not the fuel cycle of another country.
 
  • #8
Astronuc
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If one wants a clandestine operation one would probably want an LWR rather than graphite reactor, which have their own issues.

The main pathways to a nuclear weapon are not the fuel cycle of another country.
True! None of the nuclear weapons programs have utilitize foreign Pu.

Carter was simply trying to set an example, which was absurd and ill-conceived. Those who want a nuclear weapons program will ignore any such example.
 
  • #9
Morbius
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I hear a lot of talk about the law from teh 70's passed by Congress that forbade the reprocessing of commercial SNF. In my Radioactive Waste Management class today, the professor (who is a CHP/PE who specializes in waste management) said it was actually Carter, not Congress (which means, I assume, it was an Excutive Order), but Reagan lifted the ban later on.
daveb,

WRONG!!!! Reagan couldn't unilaterally lift the ban because it was NOT an Executive Order
of Carter. [ For Pete's sake, why did your Professor completely fabricate the claim that Reagan
lifted the ban? ]

It was a LAW passed by Congress, it was called the "Nuclear Non-Proliferation Act of 1978".

It was signed by Carter, but is a Act of Congress, i.e. a LAW and can NOT be repealed by order
of the President; and remains in effect.

http://www.presidency.ucsb.edu/ws/index.php?pid=30475

Dr. Gregory Greenman
Physicist
 
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  • #10
Morbius
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For high burnup fuel, that would be more or less true, but one could build a weapon with the Pu. The problem however would be the radiation which would injure the workers and damage components, but then some groups don't worry about such matters.
Astronuc,

The issue with high burnup fuel is that with higher burnups you get more of the even numbered
Plutonium isotopes; Pu-240 and Pu-242. These isotopes spontaneously fission.

The spontaneous fission means that you will have a higher neutron background, and that means
the weapon assembly has to be faster; otherwise the weapon will fizzle.

Los Alamos had originally intended to use gun-assembly for the Plutonium bomb, just as they
were planning with the Little Boy uranium bomb. However, when they got macroscopic quantities
of Plutonium; they discovered that it was infeasible to assemble a Plutonium device with a gun
method.

The problem of using Plutonium was solved by using an implosion method originally suggested by
Seth Neddermeyer, and developed and improved by George Kistiakowsky. The implosion method is
more complicated than gun assembly. Even then, a high neutron background also complicates assembly
method; even when implosion is used.

http://www.fas.org/nuke/intro/nuke/design.htm [Broken]

"Because of the short time interval between spontaneous neutron emissions (and, therefore, the large number
of background neutrons) found in plutonium because of the decay by spontaneous fission of the isotope Pu-240,
Manhattan Project scientists devised the implosion method of assembly in which high explosives are arranged
to form an imploding shock wave which compresses the fissile material to supercriticality."


These high A Plutonium isotopes are alpha-emitters; so it is TRIVIAL to shield the direct decay products.
However, with spontaneous fission; you get gammas from the fission reaction, and the fission products.

Dr. Gregory Greenman
Physicist
 
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  • #11
vanesch
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From the Carter link by Morbius:

In conclusion, I am persuaded that the new criteria, incentives, and procedures in this act will help solve the problems of proliferation. They will help to ensure that access to nuclear energy will not be accompanied by the spread of nuclear explosive capability. While I recognize that some of these provisions may involve adjustments by our friends abroad, this more comprehensive policy will greatly increase international security. I believe that they will ultimately join us in our belief that improved world security justifies the steps which we all must take to bring it about. Control over the spread of nuclear weapons on our planet is one of the paramount questions of our time.
That was the silly part of it...
 
  • #12
Astronuc
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Carter was naive. He should have discussed it with the British and French before making a unilateral decision. Hopefully someone would have asked for his rationale.
 
  • #13
Morbius
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Carter was naive. He should have discussed it with the British and French before making a unilateral decision. Hopefully someone would have asked for his rationale.
Astronuc,

Actually Carter DID discuss this issue with the British and the French. Early in his Administration,
Carter called for an international study of the nuclear fuel cycle by the USA, Great Britain, France,
and the Soviet Union. It was called INFCE - the International Nuclear Fuel Cycle Evaluation program;
and ran from 1977 to 1980.

From the outset of INFCE it was clear that Great Britain, France, and the Soviet Union were going to
to keep reprocessing nuclear fuel according to the USA's representative; former Professor of
Nuclear Engineering, Dr. Albert Carnesale [ who recently retired as Chancellor of UCLA ] as he explained
when he gave a seminar at MIT when I was a graduate student there.

The Nuclear Non-Proliferation Act of 1978 was Carter's response - an attempt to FORCE
Great Britain, France and the Soviet Union into giving up reprocessing. How the USA doing
something unilaterally forces the hand of other countries; I don't understand. But that was Carter's
"logic" [ if you can call it that ].

One of the "take-away" points I remember coming away from Dr. Carnesale's seminar was that
Carter had his mind made up; and it didn't matter what he [ Dr. Carnesale ] or any of the other
members of the INFCE partnership said; Carter wanted a world free of nuclear fuel reprocessing.

Yes - Carter was GROSSLY NAIVE, and saddled the USA was with the terrible policy of a
"once through" fuel cycle for our commercial fleet of nuclear power plants.

Dr. Gregory Greenman
Physicist
 
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  • #14
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daveb,

WRONG!!!! Reagan couldn't unilaterally lift the ban because it was NOT an Executive Order
of Carter. [ For Pete's sake, why did your Professor completely fabricate the claim that Reagan
lifted the ban? ]

It was a LAW passed by Congress, it was called the "Nuclear Non-Proliferation Act of 1978".

It was signed by Carter, but is a Act of Congress, i.e. a LAW and can NOT be repealed by order
of the President; and remains in effect.

http://www.presidency.ucsb.edu/ws/index.php?pid=30475

Dr. Gregory Greenman
Physicist
According to both Wikipedia (which is not very accurate at times and should be taken with a grain of salt), and this http://www.fas.org/sgp/crs/nuke/RS22542.pdf site, the NNPA had nothing to do with commercial reprocessing of fuel in the US, and it was a withdrawal of federal support for reprocessing that stopped it. Then later Reagan did lift the ban. I found a partial text of the NNPS here http://www.nti.org/db/china/engdocs/nnpa1978.htm and it mentions nothing about banning domestic reprocessing. Do you by chance have a link to the actual text of that law that mentions it? The link to Carter's statement you provided doesn't specifically state the ban.
 
  • #15
Morbius
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According to both Wikipedia (which is not very accurate at times and should be taken with a grain of salt), and this http://www.fas.org/sgp/crs/nuke/RS22542.pdf site, the NNPA had nothing to do with commercial reprocessing of fuel in the US, and it was a withdrawal of federal support for reprocessing that stopped it. Then later Reagan did lift the ban. I found a partial text of the NNPS here http://www.nti.org/db/china/engdocs/nnpa1978.htm and it mentions nothing about banning domestic reprocessing. Do you by chance have a link to the actual text of that law that mentions it? The link to Carter's statement you provided doesn't specifically state the ban.
daveb,

I have not found a link to the text of the NNPA. However, it DOES BAN all reprocessing in the
Unitied States.

The CRS paper you refer to above only deals with the foreign policy part of the NNPA; NOT the
domestic part.

The Nuclear Non-Proliferation Act of 1978 modified certain sections of the Atomic Energy Act of 1954;
and THAT's where you will find the explicit ban on fuel reprocessing.

In the USA, commercial reprocessing was about to go forward in the early '70s. However, a federal
Court decision blocked the licensing of commercial reprocessing because the newly [ 1970 ] enacted
Environmental Protection Act requires an environmental impact statement in order for the NRC to
issue a license to a commercial reprocessing operation.

So the Nuclear Regulatory Commission drafted the GESMO - the Generic Environmental Statement
on Mixed Oxide [ mixed oxide is the reprocessed fuel that is the product of reprocessing and which
is recycled back to the reactors. ].

With the GESMO in hand, the NRC was all set to license reprocessing facilities - then Congress
out-right BANNED reprocessing in 1978 with the Nuclear Non-Proliferation Policy Act of 1978.

http://www.wise-paris.org/index.htm...lish/frame/menu.html&/english/frame/band.html

In the 1970s the Atomic Energy Commission, a forerunner of DOE, produced desk studies on plutonium fuel use,
the most prominent of which was the Generic Environmental Statement on Use of Mixed Oxide Fuel (MOX) in
Light Water Reactors (GESMO) issued in 1976. The GESMO project was terminated in 1979 following the national
policy decision not to use MOX plutonium fuels. A completed commercial scale reprocessing plant at Barnwell,
South Carolina, was mothballed at the same time.


The USA had a COMPLETED commercial reprocessing plants at Morris, Il and Barnwell, SC which had to be mothballed
because reprocessing was banned.

Reprocessing / recycling of nuclear fuel would solve so many problems - it reduces the lifetime of
nuclear waste, it provides more cost-effective fuel as opposed to freshly enriched uranium....
The nuclear industry would be reprocessing in a heartbeat if Reagan had lifted the ban.

Alas, Reagan DID NOT lift the ban - because the ban was codified in LAW.

Dr. Gregory Greenman
Physicist
 
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  • #16
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Ok, now I'm confused. This site http://www.princeton.edu/~globsec/publications/pdf/Sciencev293n5539.pdf says what I had previously stated and quoted, but says the reason reprocessing didn't start up was economic, not political.

The reassessment initiated by the Ford administration was completed by the Carter
administration, which decided in 1977 against licensing for operation a newly built U.S.
commercial reprocessing plant. The U.S. nuclear-energy establishment complained bitterly,
and the Reagan administration reversed this policy after it came into office in 1981. By
then, however, because of the adverse economics, there was no longer any industrial interest
in reprocessing in the United States. In 1993, the Clinton administration reinstated U.S.
opposition to reprocessing
and
Storage of spent fuel is cheaper, safer, and more environmentally benign than reprocessing
My boss (Ph.D. Nuclear Engineering) now says it's the Salt Treaty (he doesn't remember if it was I or II) that banned the reproceesing so that no new bombs would be made.
 
  • #17
Morbius
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encev293n5539.pdf"]http://www.princeton.edu/~globsec/publications/pdf/Sciencev293n5539.pdf[/URL] [Broken] says what I had previously stated and quoted, but says t
My boss (Ph.D. Nuclear Engineering) now says it's the Salt Treaty (he doesn't remember if it was I or II) that banned the reproceesing so that no new bombs would be made.
daveb,

First, NONE of the special nuclear material in the USA's nuclear weapons came from commercial
reactors. The USA had special production reactors at Hanford and Savannah River to make
weapons material. The last reactor at Savannah River was shut down in 1988.

The USA HAS made new bombs since ceasing the production of special nuclear material.

New nuclear weapons usually replace older nuclear weapons; and the old weapon can be dismantled
as a source of nuclear material. The more advanced new nuclear weapon usually needs less
special nuclear material than the old ones it replaces.

So banning commercial reprocessing as a way of preventing new nuclear weapons from being built
is totally ineffective. "Reactor grade" Plutonium from commercial reactors is NOT the type of
material weapons designers like to use. Additionally, the USA has all the weapons grade Plutonium
that it needs for new nuclear weapons.

Dr. Gregory Greenman
Physicist
 
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  • #18
vanesch
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I have to say that I'm confused: I didn't know that there was still a reprocessing ban in the US as of this day. How come then that the US is part of the GEN-IV initiative which makes no sense without fuel reprocessing ?

As to the commercial benefit of reprocessing, it is probably true that as of today, there is probably not much to win with reprocessing and the once-through cycle is probably on short term the cheapest. The MOX re-use of plutonium in LWR can only save ~10% of the uranium input. The main advantage of reprocessing is the reduction of HLW volume and the reduction of its long-term radiotoxicity (by taking out the plutonium - but then you still have to do something with it) ; in other words, reprocessing as of today is mainly an ecological advantage (no matter what anti-nuclear activists may claim).
But the real reason for reprocessing is of course when breeders will (finally) be deployed on large scale. But for that to be economical, uranium needs to be more expensive than it is today, but is will probably become so in a few decades. Then one can "live" on the old stockpile of spend fuel for a few more millennia. But for that to be effective, fuel reprocessing is of course essential.
 
  • #19
Morbius
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How come then that the US is part of the GEN-IV initiative which makes no sense without fuel reprocessing ?
vanesch,

Part of the current Administration's plan is to overturn the ban on reprocessing; a proposal that has many environmentalists
up in arms. Courtesy of The New Scientist:

http://www.newscientist.com/article/dn8639.html

"Signs that the US could be about to overturn a 30-year ban on nuclear fuel reprocessing have been greeted with alarm by
environmentalists worried about the dangers of spreading plutonium around the world."


As to the commercial benefit of reprocessing, it is probably true that as of today, there is probably not much to win with reprocessing and the once-through cycle is probably on short term the cheapest. The MOX re-use of plutonium in LWR can only save ~10% of the uranium input.
MOX re-use will save perhaps !0% per cycle. The recycled Pu will be fission and tranmute more
U-238 to Pu - so that you have more Pu to recycle..... With each cycle through the reactor; you
get a couple percent of the original uranium converted to Pu-239. In fact, during the typical 3 years
that a fuel assembly spends in the reactor, about 40% of the energy that is extracted from that
fuel assembly in the 3 year period comes from fissioning Plutonium that was created in situ.

The main advantage of reprocessing is the reduction of HLW volume and the reduction of its long-term radiotoxicity (by taking out the plutonium - but then you still have to do something with it) ; in other words, reprocessing as of today is mainly an ecological advantage (no matter what anti-nuclear activists may claim).
http://online.wsj.com/public/articl...25tzFzwMfY_20070125.html?mod=tff_main_tff_top

"If the technology works, it could vastly reduce the amount of spent nuclear waste that would have to be buried in underground
storage, such as at Nevada's Yucca Mountain, set to open after 2012...
The heart of the initiative is reprocessing technology called UREX+ being developed by Argonne National Laboratory in Illinois.
It is a method of removing plutonium and other long-lived radioactive elements in spent nuclear fuel that makes the elements
reusable in nuclear power plants, but difficult to use for making nuclear weapons."

If nuclear waste is reprocessed and recycled; then the lifetime of the waste is greatly reduced. One
no longer has long lived actinides like Pu-239 with a 24,000 year half-life in the waste stream. The
longest lived fission product of any consequence is Cesium-137 which as a 30 year half life.

The whole problem with a storage repository is certifying it for thousands of years. If that requirement
is dropped because the waste is no longer that long-lived; the repository could easily be licensed.

California, for instance; has a ban on any new nuclear power plants being built in the state until the
waste depository comes online.
But the real reason for reprocessing is of course when breeders will (finally) be deployed on large scale. But for that to be economical, uranium needs to be more expensive than it is today, but is will probably become so in a few decades. Then one can "live" on the old stockpile of spend fuel for a few more millennia. But for that to be effective, fuel reprocessing is of course essential.
Breeder technology will first be deployed as "actinide burners" - reactors to deplete the current
stockpile of actines in current spent fuel.

Dr. Gregory Greenman
Physicist
 
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  • #20
vanesch
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"Signs that the US could be about to overturn a 30-year ban on nuclear fuel reprocessing have been greeted with alarm by
environmentalists worried about the dangers of spreading plutonium around the world."
There are more efficient ways to "spread plutonium around the world" :biggrin:

MOX re-use will save perhaps !0% per cycle. The recycled Pu will be fission and tranmute more
U-238 to Pu - so that you have more Pu to recycle..... With each cycle through the reactor; you
get a couple percent of the original uranium converted to Pu-239. In fact, during the typical 3 years
that a fuel assembly spends in the reactor, about 40% of the energy that is extracted from that
fuel assembly in the 3 year period comes from fissioning Plutonium that was created in situ.
Point is, as it stands now, Pu can only be recycled once in LWR, because of the isotopic degradation and the continued production of minor actinides. The only sensible way to use plutonium in several cycles is in a fast spectrum. At least in France (and in countries "attached" to the French fuel cycle) a second MOX cycle is not really possible with actual PWR designs as far as I understand. Further irradiation of the Pu vector will only increase the Pu-240 and 242 content (which is not fissionable in a thermal spectrum), and increase the Am-241 and Am-243 content.


[/i]
If nuclear waste is reprocessed and recycled; then the lifetime of the waste is greatly reduced. One
no longer has long lived actinides like Pu-239 with a 24,000 year half-life in the waste stream. The
longest lived fission product of any consequence is Cesium-137 which as a 30 year half life.

The whole problem with a storage repository is certifying it for thousands of years. If that requirement
is dropped because the waste is no longer that long-lived; the repository could easily be licensed.
Yes, but it is not sufficient to *extract* the hot and long living stuff, you must also *burn* it. And most of it only burns well in a fast spectrum.

Breeder technology will first be deployed as "actinide burners" - reactors to deplete the current
stockpile of actines in current spent fuel.
Yup, that's right. It's the whole greens misunderstanding of the nuclear issue: they've been fighting hardest exactly those aspects of nuclear technology which are most environmentally-friendly, like fuel reprocessing and fast reactors.

As to the need for "proliferation-proof" fuel cycles, I'm sceptical, for two reasons. First of all, it is very well possible to guard and protect the fuel cycle in most Western countries, and it is very easy to track stolen stuff. So it must be on the brink of impossible to steal unnoticed a large amount of material from the fuel cycle in most well-organized countries. The second reason is that a proliferator who really wants to make a bomb will succeed anyhow sooner or later without needing a foreign fuel cycle. The basic knowledge is in the open domain, and the technology is now more than 60 years old.
It is IMO more difficult to 1) get unnoticed hold of enough material by stealing and 2) make a bomb out of this "bad quality" material, than it is to produce high-quality material oneself and make a bomb out of that. Also, it's not because uranium and plutonium and other actinides are mixed, that there's a safeguard on extracting plutonium from it! Doing the plutonium extraction, it being a well-known chemical process, is not difficult to do.
 
  • #21
Morbius
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The second reason is that a proliferator who really wants to make a bomb will succeed anyhow sooner or later without needing a foreign fuel cycle. The basic knowledge is in the open domain, and the technology is now more than 60 years old.
vanesch,

I know that's what people say - but's it actually a lot trickier than what people may believe.

Even the North Korean device, "fizzled". It's really not as easy as some would believe.

Or as our Associate Director for Defense and Nuclear Technologies stated in the History Channel
"Modern Marvels" segment on "Weapons of Mass Destruction" - the North Koreans really
"screwed it up".

Dr. Gregory Greenman
Physicist
 
  • #22
Morbius
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Point is, as it stands now, Pu can only be recycled once in LWR, because of the isotopic degradation and the continued production of minor actinides. The only sensible way to use plutonium in several cycles is in a fast spectrum. At least in France (and in countries "attached" to the French fuel cycle) a second MOX cycle is not really possible with actual PWR designs as far as I understand. Further irradiation of the Pu vector will only increase the Pu-240 and 242 content (which is not fissionable in a thermal spectrum), and increase the Am-241 and Am-243 content.
vanesch,

Although a fast spectrum reactor is desired; both Pu-240 and Pu-242 have quite wide fission
resonances at about 1 eV in energy. It's really an economic decision as to whether you want
to burn Pu for mulitple cycles. For the French, I agree; it doesn't make much sense because
the storage of long-lived isotopes is not a "show stopper" for them.

For the USA; storage of long lived isotopes is really a "show stopper" and so the economics works
more to the favor of recycle.

Yes, but it is not sufficient to *extract* the hot and long living stuff, you must also *burn* it. And most of it only burns well in a fast spectrum.
Although a fast spectrum is definitely desired; as above - there are things that you can do to
"make do" with a softer spectrum reactor.

Yup, that's right. It's the whole greens misunderstanding of the nuclear issue: they've been fighting hardest exactly those aspects of nuclear technology which are most environmentally-friendly, like fuel reprocessing and fast reactors.
However, the "greens" are using a "scorched Earth" strategy. Of course they fignt the most
environmentally friendly technologies. They don't want nuclear power to be environmentally
friendly. They want to keep nuclear power environmentally UN-friendly.

They don't want environmentally friendly nuclear power. They want nuclear power to be
environmentally unfriendly - because then they can KILL IT outright.

As to the need for "proliferation-proof" fuel cycles, I'm sceptical, for two reasons.
The Integral Fast Reactor has a "proliferation-proof" fuel cycle. Dr. Till, formerly of Argonne
National Laboratory attested to that in his interview with Frontline:

http://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html

Dr. Till states that it is impossible to use the IFR waste for nuclear weapons:

Q: So it would be very difficult to handle for weapons, would it?
A: It's impossible to handle for weapons, as it stands.
It's highly radioactive. It's highly heat producing. It has all of the characteristics that
make it extremely, well, make it impossible for someone to make a weapon.


The basis of Dr. Till's statement is a study on the feasibility of using IFR waste for a
nuclear weapon that was conducted by Lawrence Livermore National Laboratory.
In fact, the adjective that LLNL used for the IFR waste as a nuclear weapons fuel was
"ornery"

Former US Senator from Illinois Paul Simon referred to this LLNL study in his letter
to the New York Times of July 5, 1994:

http://query.nytimes.com/gst/fullpa...erence/Times Topics/People/K/Kempthorne, Dirk

"You are mistaken in suggesting that the reactor produces bomb-grade plutonium: it never
separates plutonium; the fuel goes into the reactor in a metal alloy form that contains highly
radioactive actinides. A recent Lawrence Livermore National Laboratory study indicates that
fuel from this reactor is more proliferation-resistant than spent commercial fuel, which also
contains plutonium."

Dr. Gregory Greenman
Physicist
 
Last edited:
  • #23
vanesch
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vanesch,

Although a fast spectrum reactor is desired; both Pu-240 and Pu-242 have quite wide fission resonances at about 1 eV in energy. It's really an economic decision as to whether you want to burn Pu for mulitple cycles.
Ah, that's new to me ; I thought that technically it's essentially impossible. Maybe you could squeeze out a second cycle but I was of the opinion that "complete burnup" of plutonium was impossible in a thermal spectrum, simply because "moving up the A-ladder" went faster than fission.

Although I didn't even realize that there WAS a finite fission cross section for epithermal neutrons in even-numbered Pu - so thanks for pointing that out - nevertheless the absorption cross section is still ~ 3 orders of magnitude higher. One clearly sees the advantage of higher energies, because from a few hundred KeV on, the fission wins from the absorption.

Now, you can of course say that absorption in 240 is no issue, because we then make 241 which is fissile. True. But the absorption cross section and the fission cross section of 241 are comparable, so we move up a serious fraction of 241 up to 242...

One can see, in the two attachments (from the NNDC Sigma application): red is capture, blue is fission...

So you push to higher and higher A-numbers, and end up making Am 243.
 

Attachments

  • #24
vanesch
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I know that's what people say - but's it actually a lot trickier than what people may believe.

Even the North Korean device, "fizzled". It's really not as easy as some would believe.

Or as our Associate Director for Defense and Nuclear Technologies stated in the History Channel "Modern Marvels" segment on "Weapons of Mass Destruction" - the North Koreans really "screwed it up".
I didn't want to imply that making a nuclear weapon is easy. I only wanted to point out that the "essential" element for a proliferator is not really another country's fuel cycle, in as much as that country is organized enough to safeguard it. I seriously don't believe in the terrorist in his basement building a working nuclear weapon with some stolen elements of a fuel cycle without getting caught first. I also don't believe in any country HELPING a terrorist getting a nuclear weapon (because that country or its leaders will then be exposed to retalliation). I think the biggest danger comes from badly guarded existing weapons or weapon materials ; not so much from a fuel cycle in a Western country.
 
  • #25
Morbius
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I think the biggest danger comes from badly guarded existing weapons or weapon materials ; not so much from a fuel cycle in a Western country.
vanesch,

I can't give you the details - but stealing a badly guarded existing weapon is NOT a credible
concern. The present nuclear weapons in the world today have certain safeguards against
unauthorized use - and there have been advances in the safeguard technology.

That's one of the reasons for the RRW - Reliable Replacement Warhead program that the
NNSA - National Nuclear Security Administration, part of the Dept. of Energy is putting forward:

http://www.nnsa.doe.gov/docs/factsheets/2007/NA-07-FS-02.pdf

Enhance security and prevent unauthorized use
Making use of the best security technology is essential in a post 9-11 threat
environment. RRW's design takes advantage of state-of-the-art, modern security
technology to prevent use by terrorists.
Security features in the current stockpile use outdated technologies that were
available during the Cold War years.
RRW will enploy significant enhancements in security that are not availiable
throuth the current process to extend the life of a weapon.

Badly guarded nuclear material in Russia was a concern, but that problem has and
is continuing to be addressed:

http://www.llnl.gov/str/Dunlop2.html

The Material Protection, Control, and Accounting program works with Minatom civil and weapons
complexes, the independent Russian civil sector, the Russian nuclear navy, uranium and plutonium
storage sites, and reactor and fuel facilities. The program protects against both insider and outsider
theft with a host of physical security measures and systems to protect and monitor nuclear materials...
Livermore project leader Scott McAllister notes that most U.S. principles, techniques, and tools for
nuclear material protection, control, and accounting have been developed by or in conjunction with
DOE national laboratories. Livermore personnel apply this longstanding expertise when working with
their Russian colleagues..."


Dr. Gregory Greenman
Physicist
 

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