[ExI] Written for another list

Sat Aug 4 09:10:23 UTC 2012

On Sat, Aug 04, 2012 at 02:04:15AM -0400, John Clark wrote:
> 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

Exactly.

> have Thorium. That does not compute. A LFTR has to be a breeder because

No, I said it was not a breeder. That's because it wasn't. It had
no thorium salt blanket. It ran first on U-235 and then U-233 which
was bred in other reactors. Which did not ran on the thorium cycle.

The LFTR was not a thorium cycle reactor breeder. 

> 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 ran for 1.5 effective years total at 7.4 MWh. It did not ran as
a breeder, so sustained operability of LFTR either as fast or slow 
breeders is completely untested. Rebuilding a pilot would take at
least a decade, and production, *if* the pilot was deemed viable
would be at least another decade away. Meanwhile we need a substitution
rate of effective TW/year for the next 40 years. The potential
viability window for LFTR breeders as large scale source of energy
closed in late 20th century.

Stick a fork in it. It's done.

> > 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.

We're not making progress. Again, I don't have time for this, and 
you already show that you have a very selective perception of reality.

This is typical for thorium polyannas, and this is why I no longer
debate thorium polyannas. Or creationists.

> >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.