(05-29-2026, 08:23 PM)EXETER Wrote: As a former nuclear reactor operator with a degree in nuclear physics, I would like to point out several mistakes here.
There aren't "numerous" uses for 60% enriched uranium. There are 3; nuclear submarine reactors, producing Technetium 99 for medical diagnostics, and as a pathway to nuclear weapons. Iran doesn't have any nuclear submarines and doesn't have a program to build any. Iran uses its 20% enriched uranium to produce Technetium 99, not its 60% enriched uranium. That's because they don't have the spent-fuel technology to utilize the 60% stuff for medical purposes. That only leaves the weapons pathway.
Everything that can be done at 20% enrichment, can be done faster, with greater efficiency at 60%. And, I can assure you that there
are existing 'non-weapons' configurations that take advantage of that fact. So it's utter nonsense to suggest that there are only 2 other purposes for 60% enriched uranium other than weapons.
I worked on neutron beam research, and in our spare time, we used the reactor to n-dope silicon blanks for chip fab. You seem to have left that fairly common practice entirely off your very short list.
And those 'submarine reactors' are just one of the many uses of smaller more efficient Breeder type reactors.
Fast Breeder Reactors generate more power, with less fuel, and less atomic waste. In fact, they convert 'normally unusable U238' to Pu239 fuel. They can also be smaller and even portable (that's the 'submarine reactor' bit). Fast breeder reactors
require HEU primary fuel, usually in the form of MOX, rather than the volatile and highly reactive uranium hexafluoride (which is more useful for gas diffusion enrichment than for storage, or reactors, or producing isotopes etc).
Breeder reactor - Wikipedia
And neither you, nor I, know exactly what tech Iran was using, but I'm sure that all the monitoring agencies, the ones that said they found no evidence of Iran trying to make atomic weapons, had a good idea.
Also, it is far more efficient to store 440 kg of metallic uranium, in 23 liters of small portable containers, than in 127.8 liters of uranium hexafluoride. Considering that all the containers, regardless of the form of the uranium, also have to be significantly shielded.
Quote:Yes, the enrichment from 60% to 90% would only take weeks or maybe days and yet they haven't done that for 5 years. That's probably because if they tried that Israel, the US and the Five Eyes Intelligence Community would have a very high likelihood of detecting it and conclude that Iran was sprinting toward a nuclear weapon.
Israel and the US are attacking them anyway. And the "Five Eyes community" (including US ODCI) is in disagreement with Trump/Israel's current assessment.
Quote:At that point, Israel would probably start using nuclear weapons against Iran preemptively to neutralize that possibility. I don't think Iran is willing to take that chance. And I wouldn't either, if I were in their place.
You are correct that "HEU needs containment, it needs close monitoring for safety, it needs occasional handling because the radiation output needs to be controlled and it degrades most storage mediums". That's why it is stored in the form of uranium hexafluoride in special containers designed for exactly that purpose. In a recent article, the Bulletin of the Atomic Scientists concluded that Iran most likely moved all of their 60% enriched uranium to a hardened underground facility at their Isfahan nuclear research facility a year ago in those special containers, just before Trump bombed the other sites with the bunker buster bombs.
An easier task, if the uranium is metallic rather than uranium hexafluoride.
Quote:https://thebulletin.org/2026/03/analysis...e-strikes/
I suspect that somebody (looking at you, Russia) may have picked up sigint that the bombings were about to happen and tipped Iran off so they could move it. It's almost certainly still there, quite possibly untouched.
I think that Trump's tearing up of the JCPOA in 2018 and Israel's various bombing runs might have made Iran try to assure the safety of its actinide stocks, well before the latest attack.
Quote:You can't "store" HEU in a reactor core in fuel rods.
Fuel rods are usually long tubes filled with pellets of the ceramic uranium dioxide, or a mix of uranium dioxide and plutonium dioxide (MOX).
Quote:If you were to put it into a reactor core, it would immediately participate in the nuclear chan reaction there.
A "chan" reaction? Like when someone says something dumb on 4chan and everyone goes wild?
But more seriously, reactions inside a nuclear reactor can be moderated by inserting control rods that block the neutron paths between the fuel rods.
A reactor built to run with less active fuel, with the control rods mostly removed, could easily run on HEU much the same with further inserted control rods. It is entirely dependent upon the specific engineering of the reactor.
Similarly, HEU pellets could be separated from each other by interstitial damping spacers inside the fuel rod such that the total radiation would be similar to an 'LEU pellet only' filled fuel rod.
Quote:And that's the problem. Every reactor core is designed for uranium enriched to a specific level.
Yes. Remember those 'submarine' reactors? Small, portable even. Designed to require HEU. And they actually breed fuel.
Quote:If you took any of the existing reactors in Iran and arbitrarily introduced 60% HEU into it, you would immediately have a melt down.
Unless, of course, they
are actually built for it, or the control rods were sufficient, or if they increased the pellet spacing of HEU in the fuel rod.
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