Re: Whoops! The Atlantic Makes Trump Look EPIC In Cover Intended as a Smear

On 28/09/2024 17:06, Mike Van Pelt wrote:

In article <vd7m9n$uguu$1@dont-email.me>,
Peter Fairbrother  <peter@tsto.co.uk> wrote:

On 28/09/2024 01:50, Dimensional Traveler wrote:

On 9/27/2024 3:55 PM, Mike Van Pelt wrote:

I'd love to see more work done on thorium reactors.
>

That _sounds_ like an obvious answer to I have to ask what the catch is.

>
No great catch, except that thorium reactors have been massively
over-hyped.

...

Less radioactive waste? Long-term waste is pretty much the same. Claims
for less short-term waste are ... disputable.

It's actually the opposite. 

Ah yes, my mistake here, got that the wrong way round. Too late at night, can't sleep. My apologies.
I think we'd both agree that the short-term fission product waste is pretty much the same.

In general, short term waste (the really hot stuff) is fission products; the long term
waste (weakly radioactive)** is mostly transuranics.

For the uranium cycle, yes: but for the thorium cycle the worst of the long-term waste are the actinides Pa-231 and Th-229. There are others.
Not technically transuranics, but equally nasty heavier-than-lead non-fission-product long-term wastes.
Sure thorium produces less transuranics - though not none - but the heavier transuranics/actinides produced by uranium tend to have short half-lives and get consumed while still in the reactor. The lighter actinides produced from thorium tend to have longer half-lives and once the fuel is removed from the reactor and left for a few years there are more of them left.
While the results of simulations vary depending on details of the reactor conditions, for similar conditions long-term (10^3-10^4 years) radiotoxicities generally do not vary much between uranium and thorium fuels. Sometimes uranium wins, sometimes thorium,
If the actinides are reintroduced into the reactor they can in general be destroyed. This is true for both uranium and thorium.
I have nothing against thorium vs uranium - except idiots who plan trailer-sized molten salt reactors which can't cope with a post-SCRAM meltdown and which are a huge proliferation risk and claim because it's thorium it's somehow safer, and the like, and the like, and people who go on and on about the supposed benefits of thorium.
As you can probably see, the overhyping of thorium pisses me off more than a little.
Yes, at first everyone used uranium because it made plutonium for bombs, (and also because you can't start off from just thorium, you need some uranium to get the neutrons to make the Th-233) but that was then.
At present, overall it's pretty much a wash between thorium and uranium. Supply issues favour thorium a little but not overwhelmingly, known technology and existing reprocessing and other facilities favours uranium a lot. That's it.
Theoretical safety? There's no real difference.
Molten salt reactors can/could be safer, but that's a different question. They can run on uranium or thorium.
Which is the real reason why people who want to make money don't build thorium reactors when they can build uranium ones which are known to work, if only somewhat, and are easy to license and finance.
And why people who have lots of thorium and less-strict licensing and government finance are building thorium reactors.
Peter Fairbrother