Via Reuters:
A Russian-built nuclear reactor in Iran was shut down last month to limit any damage after stray bolts were found beneath the fuel cells, a Russian nuclear industry source said on Friday.
The explanation for the shutdown of the 1,000-megawatt Bushehr plant contradicted assurances by Iran that nothing unexpected had happened and removing nuclear fuel from the plant was part of a normal procedure.
“Indicators showed that some small external parts were … in the reactor vessel,” said the source, identifying them as bolts beneath the fuel cells.
The West suspects the Islamic Republic of trying to develop nuclear arms. It denies the accusations, and its first plant near the Gulf city of Bushehr is a symbol of what it says are it’s purely peaceful nuclear ambitions.
The U.N. nuclear agency said in a confidential November 16 report that fuel assemblies – bundles of fuel rods loaded into the reactor – had been transferred from the reactor core to a spent fuel pond in October, but gave no reason.
It was the second time in less than two years fuel has been unloaded from the reactor, which Russian state nuclear corporation Rosatom said in late August had been powered up to full capacity.
Second time in two years? What’s going on here? Debka thinks it might be Stuxnet all over again? They can’t be wrong all of the time.
Nuclear technology in hands where you worry about sharp scissors.
Roger, you’re missing the equal and opposite possibility – that there wasn’t anything wrong with the reactor at all (and btw, Stuxnet was never targeted at this reactor), but that this is a way to pretend to the inspectors that they aren’t harvesting Pu. To harvest Pu from a light water reactor like this, you have to pull the fuel out prematurely like this. This is exactly what they’d be doing if they were trying to get Pu out of this reactor.
I wouldn’t assume that this is good news. Good news is when the reactor runs for a few years on a fuel bundle, and burns up all the Pu that gets made early in the cycle.
Why is an explosion at the Bushehr reactor with the potential for causing a million Iranian deaths a good thing?
is concerned.
This is nothing like Stuxnet. IIRC Stuxnet was aimed at the centrifuges needed to enrich uranium. Enriched uranium can be used in either a reactor or a bomb depending on the level of enrichment, so it would make sense to target these. An enriched uranium bomb is also much easier to construct once you have the material. A nuclear reactor would only be useful in bomb making if you were trying to construct a plutonium bomb, and giving the Iranians an excuse to take the fuel rods out early would actually assist in that goal.
When the common U238 nucleus absorbs a neutron it rapidly decays into first Np239, then Plutonium 239. Pu239 is the material used in making bombs and is much easier to separate from spent fuel rods because it is a chemical separation rather than an isotopic one. If the fuel rods are left in the reactor too long, some of the Pu239 will absorb another neutron and become Pu240. Pu240 has a high spontaneous fission rate and increases neutron background such that any bomb made with plutonium containing too high a fraction of Pu240 will fizzle and blow itself apart before the reaction can produce a nuclear yield. Any reprocessing extracts the Pu239 and Pu240, and there’s no easy way to separate them.
In short, if the Iranians wanted a plutonium bomb they’d need to run their reactor on much shorter than normal fuel cycles. Blaming Israeli sabotage of their reactor for the need to prematurely remove the fuel is likely just a convenient cover.
The Iranians have already held the fuel rods inside the reactor too long to retrieve weapons grade Pu 239.
The standard drill for such production is to pull the material after no more than thirty-days. The higher the flux level, the shorter the residence time that can be tolerated.
If they are making Pu 239 it’s with their abundant supplies of HEU — and the mechanism is their numerous research reactors — the swimming pool types.
Tehran had one built and operational by 1978. They are very simple to construct. They do require HEU, for they’re too small to attain criticality with LEU.
Further, such designs permit one to ramp them up and down to suit. They don’t suffer from neutron poison impairment.
For an idea of how small a reactor can get with HEU, take a gander at K-19, the movie. Submarines, like research reactors, need to be able to swing from off to full power — at will. So, it’s customary and ordinary for submarines to use HEU reactors.
American nuclear carriers also use HEU. This is the reason why they can run for two and a half decades on one fueling. No LEU system can go that long.
Blert, you are largely full of crap. Sorry.
Enrichment in US commercial power plants is about 2.5%. Once the fuel is exposed to neutron flux, enough Pu239 is made to allow it to contibute about 10% of full power, due to plutonium fission, for the life of the fuel cycle.
The only entity in the US that uses highly enriched fuels in their reactors is the DOD, largely in naval nuclear reactors.
I’ll start with noting the one I’m most familiar with, but a lot of research reactor designs use HEU, like the original TRIGA, which stands for Training, Research, Isotopes, General Atomics (the latter is the manufacturer).
“Screw Loose in Iran” is not news.
Sounds like about time for the Emperor to shut down the Stuxnet program. It’s interfering with his plans to destroy Israel and the US.
As an aside, I wonder how many of his “voters” are writing Stuxnet code. We’re all equal after all, so no reason some of his rapper and Basketball buddies shouldn’t be writing weaponized computer software in their spare time.
The Putinator will not allow a bunch of crazy Muslims to have nuclear weapons on his border! No doubt he is behind this. Who else has the access? NOT Israel! He will milk those idiots for another 40 years “fixing” that reactor. Why does it take 40 years to build a nuclear reactor. Clearly the Russians are getting paid by the hour!
The whole Iranian nuclear threat is a Russian/Israeli conspiracy to drive up oil prices. Bibi screams and oil prices go up! Bibi screams “you cant sell missiles to Iran” and the Russians can charge even MORE money. Then they sell the passwords to Israel! Isreal doesnt have a choice in this matter.