Monday, January 17, 2011

No "Iranian Chernobyl"




The sensationalist right-wing columnist for London's Telegraph, Con Coughlin, has a story today claiming that "Russian scientists Russian scientists warned the Kremlin that they could be facing 'another Chernobyl' if they were forced to comply with Iran's tight deadline to activate the complex this summer." (via @blakehounshell)

It's possible they said that, although the piece is Coughlin's usual stew of inference and anonymous sources. But if it was scientists using that word, they were using it figuratively.

The Russians at the Bushehr plant want more time to determine, and fix, the damage done by the Stuxnet worm. They say they are also concerned about the Iranians' attitudes toward safety.

The entire history of the collaboration between the Russians and the Iranians on the Bushehr plant has been uneasy. The Russians have delayed multiple times because of Iran's nonpayment and for other reasons not made public.

But another Chernobyl - no. Maybe another Three-Mile Island, under the very worst of circumstances.

The Chernobyl reactor was an entirely different type from the Bushehr reactor, an RBMK versus a VVER. The RBMK has a design flaw that was a central part of the Chernobyl failure: its rate of nuclear reactions increases under circumstances when it should decrease. No other reactor in use today has this flaw. The Bushehr reactor also has a containment dome that the Chernobyl reactor lacked, round-topped structure in the picture. That should be reinforced concrete. So if a meltdown happened, the products would be contained, as they were at Three Mile Island.

Stuxnet is reported to have been designed to damage the turbines at Bushehr. That makes sense; what the turbines have in common with centrifuges is that both rotate at high speeds, and having those speeds jerked around will damage them, perhaps make them fly apart. The turbines at Bushehr are run by a secondary steam circuit, which means that they are not directly connected to the reactor; they most likely are in a separate building, probably that rectangular one to the right of the reactor dome. So a failure of the turbines, even a catastrophic one, should have little effect on the reactor other than to shut it down.

It might well be that the Russians used the word "Chernobyl," but if they did, it would have been in a figurative manner: very bad publicity for Russia associated with a reactor. But there would be no radioactively smoking ruin, as there was at Chernobyl.

Picture from Power Technology.

1 comment:

mbc said...

Chernobyl's RBMK was also built by 18 year old conscripts with officers overseeing not just the building efforts but what supplies could be reduced and sold on the black market during the process. Iran has made significant efforts to bring in and create in-house expertise in their nuclear program, which is 50 years newer and/or less experienced than Russia's program.

If a Russian is complaining about a dearth of safety concerns, either Iran has a significant lack of a safety culture in its nuclear program. Or, the Russians are behind on deliverables and have picked up on the safety issue delay strategy from their western counterparts. Delays are always more palatable when there is a safety issue involved.