[ExI] Written for another list

[John Clark]

On Fri, Aug 3, 2012 at 5:13 PM, Eugen Leitl <eugen at leitl.org> wrote:

> The last LFTR was not a breeder. It did not ran on the thorium fuel cycle.
>

LFTR stands for Liquid Florine THORIUM Reactor, and you say it does not
have Thorium. That does not compute. A LFTR has to be a breeder because
Thorium is not fissile but U233 is and you can breed that from Thorium.

  > It did not do online fuel reprocessing.


Don't be ridiculous, if you don't do constant online reprocessing a LFTR
will not operate and the MSRE at Oak Ridge operated for years.

> It also ran too hot.


Too hot, where did you hear that? LFTR's are  supposed to run hotter than
conventional reactors, they can do so because the liquid used doesn't boil
till 680F at atmospheric pressure and you get better thermal efficiency as
a result.

>It also had fluorine liberation due to irradtion, despite monel alloy.


Yes there were problems with that at first but they were fixed. Neutrons
weakened the original alloy but when they added fine carbon particles to it
the metal the problem was greatly reduced. And Tritium diffused into the
alloy also weakening it, so they started removing the tritium along with
neutron poisons like Xenon at the reprocessing stage and that problem went
away too.


> > It also ran three orders of magnitude below production power
>

That is true and a valid criticism, I did say it was a small experimental
reactor. However it did run at full power 87% of the time for 15 months,
the official report in 1970 said " When measured against the yardstick of
other reactors in a comparable stage of development, it is seem to be
indeed remarkable".

> There are thorium CANDUs.


There is talk about testing Thorium in a CANDU and I hope it works, but if
you use solid fuel as a CANDU does then many (but perhaps not all) of the
advantages of a LFTR are lost.

> Bullshit.
>

I'm thinking of filing a copyright infringement lawsuit.

> I can make you a U233 bomb no problem.


Maybe you can make such a bomb with no problem but others have had
difficulties. As far as I know this was attempted only twice, in 1955 the
USA set off a plutonium-U233 composite bomb, it was expected to produce 33
kilotons but only managed 22; and in 1998 India tried it but it was a
complete flop, it produced a miniscule explosion of only 200 tons. To my
knowledge no nation today has U233 bombs in their stockpile. If you have
previously unavailable information on this subject I'm all ears.

As I said you can make a bomb out of U233 but its hard as hell, so with
thousands of tons of easy to use Plutonium already produced and more made
every day in conventional reactors, not to mention thousands of poorly
guarded fully functional bombs in the former USSR, why would any self
respecting terrorist bother with U233, especially when it's so hard to
steal from a LFTR?

> U233 is separated online, so no PUREX. Very easy.
>

The liquid nuclear fuel in a LFTR does need to be constantly reprocessed
while it is operating but NOT to separate out U233 but to get rid of the
Xenon-135!  Xenon is a noble gas that is harmless to people but not to
reactors because it loves to absorb neutrons. If the reprocessing is done
incorrectly nothing blows up, the reactor simply stops; and if you actually
tried to remove even a little of the U233 at this stage the reactor would
also stop.

> Fast breeders and slow breeders have different breeding factors.


Thanks for the news flash. I could be wrong but I'm guessing that Fast
breeders are faster than slow breeders. Am I correct?

> Why don't you know that, as a thorium advocate?
>

I guess I'm a little slow.

  John K Clark
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