Instant Expert: How Can We Tell If a Country Is Making Nuclear Power or Nuclear Weapons?

It's all about enrichment

By Brooke Borel Posted 10.14.2009 at 11:23 am 12 Comments

Just about everyone insists that Iran’s nuclear program is aimed at building weapons. Iran claims it only wants nuclear power. So how do weapons inspectors get at the truth? They study the country’s supply and treatment of uranium, one of the most abundant nuclear materials on the planet.

Just one pound can produce energy equal to burning three million pounds of coal. To harness all that energy, the uranium must first be “enriched,” increasing the concentration of an unstable form of the element, U-235, which, when split, can release massive amounts of energy in what’s known as a fissile reaction. The configuration of the equipment most commonly used for this enrichment, called gas centrifuges, can tip inspectors to illicit intentions.

That’s because making uranium reactor-grade requires that 3 to 5 percent of its total concentration must be U-235 (nearly all the rest is U-238, uranium’s most common isotope). Nuclear weapons, however, require at least 90 percent. The arrangement it takes to hit that number can be a dead giveaway.

Bombs or Power?: Centrifuges are usually arranged in a triangular cascade; the layout tips inspectors to its purpose. Weapons require heavily enriched uranium, so the triangle is long and narrow; power takes more fuel, so the cascade is short and fat. McKibillo

Instant Ph.D.

Essential Jargon

Isotopes: Different forms of an element, defined by a unique number of neutrons (the number of protons is always the same)
Fission: An energetic chain reaction that occurs when a neutron bombards an atom’s nucleus and splits it in two, releasing more neutrons, which causes more collisions

Captivating Statistic

23,300: Number of nuclear warheads in the world. About 9,400 of these belong to the U.S. Russia has about 13,000.
2,200: Number of the world’s warheads that are on high-alert, able to be fired on short notice

What's Next

A new technology in the works known as laser enrichment could make uranium enrichment easier and cheaper. The method furthest along is called SILEX, which uses lasers to selectively excite and separate U-235 molecules. An enrichment plant using this technology to make fuel could be under construction in the U.S. as early as 2012.

How to Make Nuclear Fuel

Step 1: Mine It
Uranium ore is mined mostly in Canada, Australia and Kazakhstan. Then it’s concentrated into a powder known as yellowcake and combined with fluorine to make uranium hexafluoride gas, or hex.

Step 2: Spin It
Centrifuges, which range in size from less than three feet tall for older models to four stories high for more modern ones, spin the uranium gas, or hex, in a chamber at up to 100,000 rotations per minute. This creates forces of up to 485,000 Gs. Heavier U-238 atoms move closer to the wall of the centrifuge, while lighter U-235 remains in the center. The hex containing more U-235 is considered enriched; the rest is “depleted” and discarded.

Step 3: Refine It
Because U-238 and U-235 differ in weight by only about five billionths of a quadrillionth the weight of a paper clip, one go in a centrifuge is not enough to separate the two and fully enrich the hex, so it must move through additional centrifuges. How these connect to one another—a configuration of rows known as a cascade—can yield clues to the fuel’s future uses. At each row, the uranium is slightly enriched and the U-235-rich hex moves up to the next row. Since power-plant uranium requires less enrichment, cascades for reactor-grade material have fewer rows, thus are “shorter.” Uranium intended for nuclear weapons, however, requires that more than 90 percent of the hex be enriched, so it uses taller, narrower rows.

Step 4: Compress and Use It
Low-enriched hex is compressed and turned into solid uranium-oxide fuel pellets. The pellets are packed into tubes, which sit in the nuclear-reactor core of a power plant to produce steam that turns a turbine. High-enriched hex is compressed and processed into a metal that becomes the core of a nuclear weapon.

FAQ

Q. How many enrichment facilities are there in the world?
A. Around 20, and several others are under construction.

Q. What about plutonium?
A. Plutonium can also be turned into nuclear fuel, but it’s rare, so it has to be made artificially from depleted or natural uranium. Some countries have weaponized their plutonium, however, and North Korea has recently threatened to do that.

Q. Besides centrifuges, what clues can tip off inspectors?
A. The International Atomic Energy Agency, a nongovernmental organization tasked with policing the world’s nuclear activity, matches the amount of nuclear material going in and out of power facilities to make sure none is being squirreled away. In addition, inspectors can test water samples from nearby rivers and take samples from inside the plants to test for traces of weapons-grade materials.

12 Comments

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deegeezee

10/14/09 at 12:01 pm

great article! seriously, i don't think even ONE major news outlet has even attempted to explain this.

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wowlfie

10/14/09 at 12:09 pm

Israel will soon nuke those facilities at Iran. You can take that to the bank. And then we have long lines at gas stations again similar to 1974 all over again........

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coolnezz

10/14/09 at 12:52 pm

cool. i've been hearing all this jargons in the news for years and never did researched about it. this article is very useful in understanding the process.

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meyaht

10/14/09 at 3:39 pm

@wowlfie

You're sure someone will nuke Iran and the main repercussion from this is long gas station lines? You, sir, have mastered the art of being laid-back. Keep livin' the dream.

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martiniduck

from saint charles, il

10/14/09 at 11:53 pm

Here is a easy way to tell that Iran is making nuclear weapons not fuel. They have tons of petroleum. Why spend all the time and money on a nuclear power station, when you can burn cheep oil for power?

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coolnezz

10/15/09 at 5:56 am

Iran has lots of oil but not enough refineries to process it to make gasoline/fuel.
But putting that aside, still Iran can't be trusted with anything nuclear.
Need to deal with the root cause, Russia and China provide them with the technology and know-how.
Sanctions? What a joke!
With a beast like that, go for the jugular.

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blaxpear

10/15/09 at 6:45 pm

After the Bush/Chenney administration of Big Oil Execs cooked-up any reason to invade Iraq and coaxed the American public to support their twisted war, Russia lost all their lucrative oil contracts they had with Saddam's Iraq. China, also to a lesser extent. The US essentially walked in on the Russians' critical oil resource and threw it all out.

Few americans are aware of this, because there no such thing in this country as investigative journalism, comprehensive and objective reporting anymore.

As a result, Russia had to make strategic moves to secure it's long-term energy resources. Part of that involved guaranteeing that there will be no repeat of the Iraq invasion so it's only fitting that they export Nuclear technotogy to Iran.

A nuclear Iran (civilian or military) will guarantee the Russians' energy security. Just as Bush backed-off the North Korea rhetoric once it was evident that they clearly had nuclear capability. It's pretty obvious they got their tech from China.

It's simple global dynamics here. Once everyone has Nuclear capability, our leaders will start thinking before acting because there will be consequences worth considering.

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sumper5

10/15/09 at 10:35 pm

It's just simple issue, just think when everybody has nuclear and then they bomb each other like grenade, of course people will find another planet to live.
so you guys don't worry ok. US goverment will find suitable planet for us to live and see more plutonium so that we can play nuclear grenade's again.

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Ammar

10/16/09 at 9:18 am

if this is so obivious to guess if iran is making wareheads or not than i think IEA is run by a couple of fools who do what ever US tells them to do.

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semperloco

10/16/09 at 5:49 pm

blaxpear is right about lack of investigative journalism. If someone would point up the idiocy of us disarming and scrapping nuclear weapons research while the rest of the world is arming up, I can only hope it would help. The old theory of MAD (Mutual Assured Destruction) was developed because the superpowers had nuclear weapons (and still have). The worst case scenario, though is to have a mad person with nuclear capability. Iran's leader has said he wishes to be martyred and that he wants to destroy Israel. Israel would defend itself and should. A preemptive strike would be wise, but we would need to have some nuclear subs in place to make sure Russia sits it out. That would not be about oil. It would be about national survival. I just don't think we have a backbone in the POTUS office.

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Reason

11/08/09 at 7:01 pm

This was indeed a nice encapsulation of the enrichment process and it is important to be able to read Iran's intentions, but when it comes to deciding what to do about it, I can't help but wonder, "Who are we to decide which sovereign nations can have nuclear weapons and which can't"? I'm totally in favor of using every diplomatic and financial tool at our disposal to prevent an uncooperative theocratic government from developing nuclear weapons but beyond that, if they want to beef up their security and clout by possessing powerful deterrents, so be it. When those deterrents are unleashed we deal with them. I believe that the best method of solving this problem is to drop all sanctions. Open the borders to the free flow of goods and ideas. Coca-Cola, Levis, computers, etc. The people of Iran are, for the most part, a good and intelligent people who are currently struggling to remove the yokes of oppression. An attack on Iran, on the other hand, will only serve to unite all Iranians against the attacker, just as all Americans united after 9/11.

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Occam

11/17/09 at 12:31 am

Martinduck-
Iran is actually being very strategic with its resources. Being one of the few nations with petrol by 2030, it knows it will get much more money from its oil by sale to 1st world countries, not by domestic energy. Hence, the payoff for relatively cheap nuclear - something they have a right to under the NPT (which Israel has not ratified).

Instant Expert: How Can We Tell If a Country Is Making Nuclear Power or Nuclear Weapons?