Energy From Thorium Discussion Forum

Many on the forum worry about chlorine-36, the activation isotope of natural chlorine-35 (and to a lesser extent of other nuclides depending on which are used, eg potassium and chlorine 37 n,2n).

But this seems like fear mongering to me. A three hundred thousand year half life means the activity is low, and it is only a weak beta emitter. It also has a fairly short biological half life, as almost all forms of chlorine compounds don't bio-accumulate (and the ones that do, perhaps dioxins, are unlikely to be produced at all from radwaste).

In fact chlorine-36 is produced from cosmic rays in the atmosphere, and was produced from nuclear weapons testing close to the ocean (island tests). No one seems to be affected by this in their health. Are there any documented cases of chlorine-36 radiation poisoning at all?

Health effects of chlorine-36 are limited according to the ead:

http://www.ead.anl.gov/pub/doc/chlorine.pdf

This won't be acceptable to greens, but one could always just dump it in the ocean. Lot of nonradioactive chlorine to dilute it.

This thought occurred to me as well, but I was afraid to even mention it just imagine what the Greenpeace luddites will cry. Their coal and oil friends will probably help finance some fancy posters showing the bad nuclear companies dumping glow in the dark fluid in the ocean, and even throw some linear no threshold junk science at it too. Its bad PR, though ironically its probably the safest solution to dump it right in the middle of the ocean...

Its not a good idea to assume people are reasonable. However, education helps a lot, and I find that once people learn more about nuclear technologies they are much more reasonable.

I don't see why we'd need to dump it anywhere. If we're actually operating a chloride reactor regime, recycling the fuel salt doesn't seem like that much work compared to recycling just about anything else, especially if we need to enrich it anyways. Maybe in the distant future several centuries out, when one might expect we'll have more advanced waste management solutions anyways.

That would be me.

I'm definitely a scare monger.

Moreover, Its not a good idea to assume that POLITICS is reasonable -- with respect to nuke regs, that is.....

Seriously, whats the beef with cl-36? Its not something that is the least bit difficult to recycle as a salt, unlike most other radwaste. Sure its got biomobility, but so what? If we dumped all the Cl-36 directly into the environment (wasteful and silly given it would be stuck with valuable Cl-37), given its short biological half life and low radioactivity, it would be vastly outmatched by K-40 in everyone's bones that is stuck there for your entire life.

Hey, I didn't mean to be rude or suggestive. Just making an appeal to fairness, if it comes through to 1% of the population I'd be more than satisfied already

But now that you're here, maybe you could explain things a bit, because its kinda strange that you like bone-seeking plutonium and at the same time consider mildly radioactive, non-accumulating chlorine-36 as a big radiotoxicity issue.

I think Dezakin is right. The reactor salt is productive. Chlorine-36 has a higher absorption cross section than chlorine-37 so it will burn out to much lower levels as well. This suggests a possible long term chlorine-36 reduction method that I've been thinking about for some time: we burn out the Cl-36 and in order to compensate for the smaller amount of Cl-37 burning we add radioproduced chlorine-37. Perhaps calcium which has some neutron,alpha reactions producing argon-37 which decays to chlorine-37. Because argon is a gas we'd need to make little side circuit since it would pass out with the offgas stream. What other elements produce chlorine-37?

The issue is the corrosion caused by 37S. Kirk added links about both the corrosion and the cheapness of the isotopic separation.

Kirk and I discussed it here:

http://energyfromthorium.com/forum/viewtopic.php?f=5&t=134