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News Planning for a new nuclear age

  1. Apr 15, 2007 #1

    Astronuc

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    http://news.bbc.co.uk/2/hi/programmes/from_our_own_correspondent/6550029.stm

    Under the Atoms for Peace Program, the nations which had developed nuclear energy were supposed to share the technology - for peaceful uses.
    http://en.wikipedia.org/wiki/Atoms_for_Peace

    http://en.wikipedia.org/wiki/International_Atomic_Energy_Agency
    http://www.iaea.org/index.html


    With energy concerns on the horizon, the world is reconsidering nuclear energy as a major contribution to energy supply. If that be the case, there are significant issues such as proliferation and safety that must be addressed. Undoubtedly there will be conflicts over who controls access to the technology and materials.

    http://news.bbc.co.uk/2/hi/programmes/from_our_own_correspondent/6550029.stm
    http://www.world-nuclear.org/
     
  2. jcsd
  3. Apr 15, 2007 #2
    I think that no matter what a newer alternative to fossil fuels may be. It will happen only when the big energy companies like Exxon allow it to happen.
     
  4. Apr 15, 2007 #3

    russ_watters

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    Exxon has no control over what type of power plants Excelon builds.
     
  5. Apr 15, 2007 #4

    ShawnD

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    How about just not-share the technology with countries we don't trust? US, Canada, France, UK, Japan, and Russia all have nuclear power. Countries like Iran and Iraq do not.
    The only countries that seem to have a shortage of energy are the ones that have a shortage of money (African countries), and in that case they can't afford to build nuclear plants anyway. What exactly is so bad about keeping our current system? The G8 countries have nuclear, and we use it. The middle east has lots of oil, and they use it. Africa has no money but lots of resources, and they'll eventually make use of them.

    If the concern is about an energy shortage, there really is no crisis at this time, or even in the near future (this stuff will run out in literally hundreds of years).
    If the concern is about nuclear armament, that is also not a problem because nobody is forcing us (G8 countries) to build nuclear reactors for Iran.
    If the concern is global warming, that's a totally different can of worms.
     
    Last edited: Apr 15, 2007
  6. Apr 15, 2007 #5
    Well I would submit to my colleagues that Iran--since it falls in the crosshairs on a couple of different dimensions--is a perfect test case for discussion. To summarize an obviously far more nuanced situation situation:

    thay claim to want to develop ambitious nuclear energy program. They have several near neighbors, most notably Israel in current proximity with nuclear weapons. The ME is a smoldering tinderbox in general. Those with nukes are treated a lot more deferentially than those without.

    So should they be told no, not under any circumstances, or allowed to develop breederless technology iff agreeable to close oversite with random inspections, on up to the other end of the spectrum. Not taking a particular POV, just underlining what a Gordian knot of developing a coherent strategy alluded to in Astronuk's thread.
     
  7. Apr 15, 2007 #6

    ShawnD

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    If Iran is really interested in this stuff, give them the technology for thorium and maybe plutonium reactors. Uranium nuclear bombs are way too easy to make whereas plutonium bombs are ridiculously complicated, and I don't even think you can make a bomb out of thorium.

    Thorium should satisfy their desire for nuclear, and if they say no, it's an obvious sign that they wanted nuclear technology for nuclear arms. In that case, they can go to hell.
     
  8. Apr 15, 2007 #7
    Unless there is a merger or buy out.:rolleyes: Which is what I was really getting at when I said that the big energy companies will control energy production of all types. The assets of big oil far out weighs that of the nuclear industry. At one point Exxon was in the nuclear fuel production business.
     
    Last edited: Apr 15, 2007
  9. Apr 15, 2007 #8

    ShawnD

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    Which is bad because.... ?
     
  10. Apr 15, 2007 #9
    Well if a bomb can't be made from thorium (al least not a nuclear one, could make a mess I'm sure) maybe that suggests a tiered system where the entry level is with thorium or whatever recognizing dirty bomb potential, black market value, etc. After ten years of playing by the rules and donating to an escrowed acct a couple cents per KW to pay for policing and provide a good faith bond, maybe they get moved up the ladder.

    Pakistan is ruled by General Nutcase, yet we need to curry favor and all of a sudden they are moved two rungs up the ladder. For how long will he be an ally or even in control. But this is how the US does things much too often. Saddam, a perfect example of giving technology away when it might suit our (and by our, I recognize that this is not necessarily we, the peoples interest) temporary interest only to have it bite us in the butt. Whoever is in charge of overseing such an important process needs to have the power to call the shots. But here again, if the US, UK, France or whomever doesn't buy into the whole enterprise, and along comes Jeb in 2012 saying the treaties are meaningless, then it is back to the incoherent policy of present.
     
  11. Apr 15, 2007 #10
    A thought:
    How about Iran gets their electricity from a neighboring country, like Turkey? We move/dismantle their current reactor facilities, and put them up in a "reasonably" friendly country nearby and run powerlines on in?
     
  12. Apr 15, 2007 #11

    Astronuc

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    Thorium fuel still requires some U-235 or Pu-239 initially, until one can make U-233 from the thorium. And one could make nuclear weapons of U-233. Pu-239 is a major proliferation issue, and its complicated, but not ridiculously complicated.

    And don't forget China has nuclear technology, so do both Koreas, and India, as well as most European nations (including E. Europe), as well as South Africa, Brazil and Argentina.

    I believe the Iran has its own uranium deposits, and could very well develop a self-sufficient nuclear energy program.
     
  13. Apr 15, 2007 #12

    Astronuc

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    Technically that would work. Politically - no nation voluntarily surrenders their energy supply to another country. And there is the matter of sovreignty.
     
  14. Apr 15, 2007 #13
    Why? Do you think any country in their right mind would rely on something as vital as power to another country, especially in the middle east? Need I remind you about Russia stopping fuel to Europe for demanding high prices until they paid?

    No way would anyone in their right minds agree to those conditions. I dont want to rely on my power coming from Canada or Mexico, do you?

    I think your idea is unreasonable.
     
    Last edited: Apr 15, 2007
  15. Apr 15, 2007 #14

    ShawnD

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    Sorry that I'm not too familiar with the workings of nuclear cycles. I've only ever known U-235 to be easily made into a bomb while 238 is essentially useless. That one thorium turns into, 233, I can't find too much information on.

    If Iran has its own uranium, how is any country capable of stopping their nuclear program? Do we keep close tabs on absolutely everything they do?
     
  16. Apr 15, 2007 #15

    Astronuc

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    Presumably by force. There have already been comments about the use of military intervention to destroy the facilities - but then that would constitute an act of war.

    So the world must rethink the use of nuclear energy.
     
  17. Apr 15, 2007 #16
    The answer to that question is yes. We, and the world community should keep VERY close tabs on everything EVERYONE with nuclear technology does. I dont care who they are, if they have nuclear technology the world community better know what is going on. See: Russia, a very BAD example of nuclear technology.

    I was watching a program on the Discovery Channel about EMP weapons. Apparently Russia had made many of these weapons that fit inside a suitcase and could cause major damage to electrical systems inside major cities......long story short.....most of them are now missing and its a big security concern.

    So I dont care who you are or how big a superpower you claim to be, if you have nuclear weapons you better have every last document and part under close watch at all times.
     
    Last edited: Apr 15, 2007
  18. Apr 15, 2007 #17
    Been a while since I have seen an update, but plenty is missing from our stockpile as well. All of which argues IMO a move to steer clear of this path and develop fusion. If we poured the worlds resources into something analagous to the Manhattan project with a 20 year deadline, all these other issues such as AGW, nuclear prolif, etc would be moot. Not to say that countries would stop building bombs, but taking the fuzz out of the image as in what materials are going where would sure help police actions. It may serve an additional purpose as we reach the end game of fossil fuel supply to not battle over crude reasons and choose really important issues such as religion.
     
  19. Apr 19, 2007 #18

    Art

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    I'm curious as to how U235 changes U238 to Pu239? If U235 donates a neutron to U238 why doesn't this simply create U239 a new isotope of U238?? Or is it the case that U235 picks up an alpha particle and gets an extra 2 protons and 2 neutrons to make Pu239 Or am I totally wrong about the processes??
     
    Last edited by a moderator: Apr 19, 2007
  20. Apr 19, 2007 #19

    Astronuc

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    Fissile isotopes U-233, U-235, Pu-239, Pu-241 produce two or three neutrons during the fission process. At least one neutron must survive to fission another fissile nucleus. The other neutrons are captured by other non-fissile atoms.

    In the case of U-238, it absorbs a neutron and becomes U-239, which decays by beta emission to Np-239, which subsequently beta-decays to Pu-239. That happens in any reactor using natural or enriched U (which is predomninatly U-238, then U-235, and perhaps traces of U-234 and U-236.

    Similar, Th-232 absorbs an neutron becoming Th-233 which beta decays to Pa-233, which beta decays to U-233. Thorium fuel is often/usually blended with U-235 until enough U-233 has been produced.

    Even if U-235 absorbs a neutron, there is about a 16% chance that it will emit a prompt gamma and become U-236, which absorbs a neutron to become U-237. Similarly Np-239 could absorb a neutron becoming Np-240 and then decay by beta emission to Pu-240. And Pu-240 could absorb a neutron and become Pu-241, which beta decays to Am-241, could absorb a neutron and become Pu-242, which undergoes alpha decay. Am-241 may absorb a neutron becoming Am-242, which beta decays to Cm-242.

    The isotopes heavier than U are termed transuranics.
     
  21. Apr 19, 2007 #20

    Art

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    So presumably beta decay must convert a neutron into a proton then? Does it then capture an electron to neutralise the extra positive charge? And what's the half life of Np239?

    Can U235 be converted directly to Pu239 by absorbing an alpha particle?

    Oh and last question why does the plutonium need to be extracted? As Pu239 is fissionable wouldn't this just become part of the reactor fuel?
     
    Last edited by a moderator: Apr 19, 2007
  22. Apr 19, 2007 #21

    Astronuc

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    Correct. In beta decay, the nucleus increases in positive charge. It will attract an electron from another atom, or perhaps a free electron knocked out of another atom by the beta particle. The beta particle slows down and is eventually absorbed by an ion, perhaps not too far from where it was emitted. Beta particles (nuclear electrons), alpha particles and gamma rays all interact with atomic electrons in the matter through which they pass.

    Very unlikely. Pu-239 undergoes alpha decay to form U-235. Try this link - http://www.nndc.bnl.gov/chart/reCenter.jsp?z=94&n=145 - then press the '1' under the ZOOM (on the righthand side of the chart).
     
  23. Apr 19, 2007 #22

    Art

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    Sorry for all the questions Astronuc it's just that one hears so much about nuclear fission but there is very rarely any explanation of the technical aspects.

    One question I added to my previous post was why does the plutonium need to be extracted? As Pu239 is fissionable wouldn't this just become part of the reactor fuel? Or is it it's long half life that's the problem? I'm curious as I've read the US were considering building MOX reactors to use up their surplus Pu239 stock so I wondered why Pu239 is a suitable fuel in them but not in the current reactors.

    Also I see types of fission of any given radioctive element is expressed in % terms. I take it there are assignable causes (ie nuclear interactions with other particles) dictating how a particular atom fissions i.e. what the fission fragments will be or is it purely spontaneous and random?
     
    Last edited by a moderator: Apr 19, 2007
  24. Apr 20, 2007 #23

    Astronuc

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    No problem. I am pleased to answer your questions.

    Each fission produces two nuclei, which are called fission products. Some fission products such as Xe-135 and Sm-149 (samarium) have high neutron cross-section (i.e. they capture neutrons very easily), and they compete with the fissile material for neutrons. Pu-239 is produced in commerical light water reactors (LWRs) and in fact accounts for nearly half the fissions in high exposure fuel, IIRC.

    The US (and Russia) are supposed to be converting the weapons grade (WG) Pu-239 (+ Pu240), which is in metal form for weapons, into nuclear fuel. The plan is to take the Pu metal, convert it to an oxide PuO2 and blend it down (dilute it) with depleted U (residual from the enrichment process) in the form of UO2. The oxide would then formed into ceramic pellets (small right circular cylinders) and loaded into Zr-alloy tubing (which seal-welded at both ends with metal caps of Zr-alloy), which comprise the fuel rod. The fuel rods are loaded into assemblies, which are loaded into the core. MOX can be used in current power reactors, so there is no need for a special reactor. People do refer to MOX cores.

    Some nuclei undergo sponstaneous fission (SF), in addition to simply decaying by beta or alpha emission. The % indicates that a small fraction of the nuclide will undergo spontaneous fission. Otherwise, an extra neutron is required to cause fission.

    Some of these matters are discussed in the nuclear engineering forum. In particular there is a thread on the asymmetry of fission.
     
  25. Apr 20, 2007 #24
  26. Apr 20, 2007 #25

    Astronuc

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    We can certainly discuss fusion, but it is still very much in research and is not yet perfected as a viable source of energy.

    Nuclear technology based on fission has 50+ years of experience. The new plants/reactors in planning are based upon this experience.
     
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