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What is Iran referring to here?

  1. Feb 17, 2006 #1
    Can anyone enlighten me as to what these types of centrifuges Iran is talking about below ("modern centrifuges") are - and how they might differ from other types?

    Do they not allow for the production of weaponized nuclear material?

    Would such a process be easily modified (if they wanted to produce weaponized nuclear material) or, iyo, the West find this an acceptable solution?



    Iran sets terms for UN nuclear checks
    Friday 17 February 2006 4:26 PM GMT

    Iran says it only wants to produce low grade uranium

    Iran is ready to ask its parliament to ratify an accord allowing UN inspectors to resume snap checks of its nuclear facilities on certain conditions, Iran's embassy in Paris said on Friday.

    The Iranian statement, which came the day after France accused Iran of pursuing a secret military nuclear programme, sketched out a three-stage process to end a standoff with the international community over Iran's nuclear programme.

    Ratification of the Additional Protocol of the nuclear Non-Proliferation Treaty (NPT), which gives the UN nuclear watchdog greater powers to inspect suspected nuclear facilities, has been a key demand made of Tehran by Western nations.

    Iran, which began implementing the protocol in 2003, but has never presented it to lawmakers for ratification, stopped applying it this month after the board of the International Atomic Energy Agency (IAEA) voted to report Tehran to the UN Security Council.

    "If such guarantees were accepted, Iran would agree to submit to parliament for ratification the additional protocol"

    Iranian embassy statement

    The embassy statement linked the new offer to the West accepting its use of "modern centrifuges, proposed by some US and British scientists, which permit only limited enrichment.

    "If such guarantees were accepted, Iran would agree to submit to parliament for ratification the additional protocol," it said.

    Russian offer

    Iran says it only wants to produce low-grade enriched uranium, suitable for use in power reactors. But many Western countries fear it could use the same technology to manufacture highly enriched uranium, which can be used to make atomic warheads.

    It was not immediately clear why the embassy had issued the statement rather than government officials in Tehran.

    Iran has been stressing on a
    negotiated solution to the crisis

    Several senior Iranian officials have stressed in recent days their desire to find a negotiated solution to the nuclear issue.

    "Today, we are a nuclear country and we are ready to negotiate with other countries to remove their concerns," Gholamreza Aghazadeh, head of Iran's Atomic Energy Organisation, told state television on Thursday.

    "If a proper solution is suggested, we are ready to negotiate; they have to stop threatening us with sanctions and other threats," he said.

    "I believe that apart from America and Israel, the other countries want to find a way out of the current situation and we want a solution as well, so everyone should make an attempt to resolve the issue," he added.

    The embassy statement made no mention of Moscow's proposal to enrich Iranian uranium on Russian soil and return it to Iran for use in atomic reactors, a move designed to ease concerns that Iran could produce bomb-grade uranium.

    Russia and Iran are due to hold talks in Moscow on Monday about Russia's offer to enrich uranium for power station fuel on Iran's behalf.
  2. jcsd
  3. Feb 17, 2006 #2


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    Science Advisor


    These cetrifuges are very high speed centrifuges that can create a large enough
    centrifugal force - that they can be used for separation of isotopes. These are not
    the centrifuges found in a hospilal laboratory for fractionalizing blood.

    A single centrifuge can only make a relatively small degree of separation. The same
    is true for the gaseous diffusion stages in the Oak Ridge K-25 enrichment plant.

    However, just like they do at K-25 with the GD stages, centrifuges can be
    "cascaded". That is they are linked "in series". Each centrifuge has one input and
    two outputs - one output is slightly enriched in U-235 with respect to the input,
    while the second output is slightly depleted in U-235 with respect to the input.


    [The above shows a cartoon of a gaseous diffusion cascade - but the GD
    stages could just as well be replaced with centrifuges.]

    The slightly enriched output is sent to the input of the next higher stage; while the
    slightly depleted output is sent to the input of the next lower stage. [ In a grade
    school analogy - if you pass 6th grade; you go on to 7th grade. If you fail 6th grade,
    you have to repeat the 5th grade ]


    With the cascade, you can get any degree of enrichment you want - using all the
    same centrifuges. The more stages you have - the higher the enrichment.

    So if you have the technology to create low enriched uranium for reactors - in which
    you hook the centrifuges to a certain number of stages - you just put more of the
    same stages until you get whatever enrichment level you desire - all the way up to
    weapons grade.

    From the Federation of American Scientists:


    "Modern gas centrifuges change this picture. ...Moreover, centrifuge enrichment plants are modular, much smaller than gas diffusion plants, and use potentially just five percent of the electrical power of a gas diffusion plant. Thus, they not only make the development of nuclear weapons easier, they make more difficult both the monitoring of supposedly peaceful uranium enrichment for nuclear power and the detection of clandestine bomb-making programs."

    The bottom line is - if you allow the Iranians to have enrichment technology that will
    provide them with low enriched reactor fuel; then they've got the technology to
    make high enriched bomb fuel. They just have to string more centrifuges together.

    Dr. Gregory Greenman
    Last edited: Feb 17, 2006
  4. Feb 17, 2006 #3
    Uranium hexafluoride is corrosive though, but Iraq purchased aluminum tubes? I might be mistaken, but nickel is used for containing UF6, right? Is it easy just to coat the tubes themselves, or does corrosion not matter in this case?
  5. Feb 17, 2006 #4


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    Anhydrous UF6 is not very corrosive, and that is the form used in enrichment and subsequent conversion lines.
  6. Feb 18, 2006 #5
    Thanks Morbius! Just what I was curious about.
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