Created on Sunday, 07 October 2012 16:38
Written by Mark Langfan - Arutz Sheva
Irans uranium enrichment
With the current disclosed rate of UF6 20% growth, Iran will have enough 20% U235 stock for more than one nuclear bomb's worth of 90% U235 by this coming April 2013. Here's how they did it and why Bibi was right - yes, soon they will be unstoppable.
Bibi's bomb graphic and scrawled red line did what Obama will never do: Draw a red line for Iran's nuclear program.
And while the bomb graphic wasn't perfect, it was damn good, and got people's attention to the fact that, as of now, the world has not any Iranian nuke red line.
In order to understand the Iran nuke red line debate, one must understand a couple of easy-to-understand principles of chemistry and physics upon which the uranium enrichment process is based. Then, one will have a better idea of what Bibi's bomb graphic really meant, and what has to be done next.
As I have explained in earlier essays, natural uranium is composed of two main isotopes, U235 and U238. The heavier isotope U238 is bad for nuclear bombs in that it has relatively unreactive nucleus compared to its isotope cousin extremely reactive U235’s nucleus which has the same number of protons and three less neutrons. That's why its atomic weight number 235 is three less than 238.
Those extra three neutrons in U238 make the uranium atomic nucleus incapable of a chain reaction necessary for a nuclear bomb. So the key to the uranium enrichment process is to isolate the U235 atoms, separate the U235 atoms and concentrate them in an ever higher concentrations. A concentration of 90% of U235 (or 10% U238) is necessary for use in a nuclear bombs. That's why 90% U235 is called "weapons grade" uranium.
One needs about 40-50 kilograms of 90% uranium in metal form for one nuclear gun-type bomb. Metallic uranium is just like any other metal like gold or platinum.
So how does one actually enrich uranium? The natural uranium metallic low percentage U235 uranium is mixed with the element fluorine and made into a gas called uranium hexafluoride UF6. This is just fancy name that means there are six fluorine atoms bonded to one uranium atom. This UF6 gas is then spun in high-speed centrifuge in a series of connected high-speed centrifuges to make ever higher concentrations of U235 at each centrifuge. The way this is done is the centrifuge spins out the heavier U238 UF6 gas into the rim of the centrifuge leaving the lighter U235 UF6 gas in the core of the centrifuge.
In sum, U238 gas spins out to rim, U235 gas stays in core, U238 gas spins out to rim, and so on.
This higher concentration U235 UF6 gas in the center of the centrifuge is then sucked out of the core by a pipe and piped into the next centrifuge which repeats the process. By stringing a thousand centrifuges together in a series one after another, in this way, the core U235 UF6 gas which gets sucked out of the previous centrifuge, gets a little more concentrated every time it gets sucked out of a centrifuge.
The higher concentrated U238 UF6 gas in the rim of the centrifuge gets re-fed and cycled back into the enrichment cycle at an earlier stage. Little by little, the cascaded siphoned-off uranium U235 UF6 gas gets a higher and higher concentration of U235 until the enrichment operator hits his concentration goal.
Here's how it progresses:
Centrifuge #1: In U235 UF6 20.00%, out U235 UF6 20.03%
Centrifuge #2: in U235 UF6 20.03%, out U235 UF6 20.05%
. . .
Centrifuge #1000: in U235 UF6 89.96%, out U235 UF6 90.00%
Then, the uranium element is isolated and chemically extracted from the high concentration U235 uranium hexafluoride UF6 gas, and is turned into a metal discs just like a gold ingot.
Since the UF6 gas had 90% of U235, the isolated and metalized uranium from this enriched gas has the same enrichment level of 90% U235 weapons grade uranium.
In August 2012, Olli Heinonen, a former IAEA expert, estimated that it would take Iran about "a couple of months" to run an Iranian stockpile of 20% U235 UF6 stock of about " 300 kilograms-an amount sufficient, with additional enrichment, for more than one nuclear weapon." This 300 kilograms of 20% U235 UF6 will boil down to enough 90% U235 for one bomb worth of U235.
As of August 30, 2012, the International Atomic Energy Agency (IAEA) declared Iran in open disclosed possession of 189.4 kilograms of 20% UF6 gas which was 43.8 kg more than Iran disclosed to the IAEA and published in its May 25, 2912 report.
This rate of 20% UF6 Iran stockpile growth means about 15 kilograms of UF6 20% U235 per month. If this rate is maintained, this growth rate will hit the Heinonen 300 kilogram U235 stock target in 8 months from August 30, 2012 or April 30, 2012.
This, of course, assumes Iran is not hiding any UF6 stock, which a weak assumption. But, with the current disclosed rate of UF6 20% growth, Iran will have enough 20% U235 stock to spin down to "more than" one nuclear bomb worth of 90% U235 by this coming April 2013.
The confusion in Bibi's bomb graphic was Bibi's use of 70% and 90% labels which could be confused with 70% and 90% enriched uranium. The reason this is confusing is no one enriches past 90%, so the Iranians would never cross the Bibi's red line even if they were building a nuke.
What Netanyahu probably meant was not the percentage of uranium enrichment, but just simply how close the Iranians were to actually building a final nuclear bomb. So, Bibi's meant if the Iranians are only 10 percent away from the bomb, then that's a red line.
Maybe a football analogy would have been a little more accurate. So, if the Iranians are "goal-to-go," then it's time to forcibly stop Iran.
But Netanyahu was the man who stood on the UN podium, faced down the world that thinks “football means “soccer,” and Bibi got everybody's attention with his great bomb graphic, so that is great, in and of itself. Who am I, or anybody, to complain?
However, the real problem is once the uranium gas or uranium metal has been enriched to a high concentration of U235, no amount of bombing (either conventional or nuclear) will destroy the highly enriched U235 uranium contained in the UF6 gas centrifuges, or stop the Iranians from easily recovering the highly enriched U235 uranium from the debris of the bombed out centrifuging works.
For example, in a conventional attack on Fordow which houses thousands of gas centrifuges built into cascading centrifuges, the attacking bombs will (assuming they make it through the concrete) blow up the gas centrifuge containers containing highly pressured UF6 gas. But the uranium UF6 gas will interact with the immediate atmosphere and do two things:
1) at the pressure and temperature of the bombed out building UF6 will turn from UF6 gas phase directly to UF6 solid phase without going through UF6 liquid phase (this is called de-subliming) and ultimately all the UF6 gas will 2) chemically interact with the water vapor contained in the atmosphere, and chemically produce uranyl fluoride UO2F2 which is a bright orange color solid powder which becomes yellow on contact with water.
This uranium powder still will have the relatively high concentration of U235. And this uranyl fluoride solid powder will be easily extracted from the bombed out Iranian nuclear facility debris. So, the Iranians will be able to recollect and recover almost all their highly-enriched U235 uranium from the bombed-out facility. The only thing they have to do is just build a new cascade centrifuge facility.
The terrible consequence of all of this is that the longer Iran is allowed to enrich uranium and stockpile the enriched U235, the shorter time there will be after any possible attack on Iran in which Iran can actually recover their enriched uranium and actually build a bomb.
Therefore, while Bibi's bomb graphic was a great first step towards educating people about the need for a red line for Iran's nuke program, it should be followed up with a clearer definition of what exactly is the level of enrichment of U235 would constitute a "clear, and present danger" to the world.
A good benchmark and starting point would be: how many kilograms of 20% U235 in the hands of Adolf Hitler in 1938 would have represented a "clear and present" danger to Western civilization so as to require military intervention. And, if Adolf Hitler had openly disclosed 189.4 kilograms of 20% UF6 gas in December 1939 would President Roosevelt have rejected an urgently requested meeting with Winston Churchill in favor of a shout-out with Jay-Z?
For more information, visit www.marklangfan.com.
mark langfanMark Langfan: The writer, has created an original educational 3d Topographic Map System of Israel to facilitate clear understanding of the dangers facing Israel and its water supply. It has been studied by US lawmakers and can be seen at www.marklangfan.com