I read a funny thing the other day – China is nervous about Japan making atomic weapons and has complained to the International Atomic Energy Agency that Japan has over 1,400 lbs of plutonium that it did not report (NYTimes).
The Japan Atomic Energy Commission thought the 640 kg of Pu was exempt from any reporting requirements (Japan Times). The Pu is part of the mixed plutonium-uranium oxide fuel program (MOX fuel) at the Genkai nuclear plant in Saga Prefecture owned by Kyushu Electric Power.
China’s fear is actually amusing since this Pu cannot be made into weapons. Also funny is China’s faked outrage. They know as well as anyone that this Pu is from power reactors and has the wrong isotopics for weapons. In fact, blending down weapons-grade Pu into MOX is the way we get rid of weapons-grade Pu. If you want nuclear weapons, it’s way easier to just build a weapons reactor and reprocess that spent fuel. That’s how we all got Pu for weapons in the first place. You get many more weapons much faster.
Which is why North Korea took the weapons reactor path. And why we don’t care that Iran recently fired up a nuclear power reactor.
Funny that none of the news agencies reporting on this story let their readers know this batch of Pu could not be used for weapons, and instead lent credence to China’s faux rage. This Pu falling into the “wrong hands” wouldn’t be nearly as bad as the “wrong hands” just getting some 137CsCl powder from a few sympathetic food irradiation facilities in the Middle East and southern Asia (Mitt Romney, Iran and Dirty Bombs).
Now that material makes great dirty bombs!
Much more critical to the idea of Japan wanting The Bomb is 300 kg of actual weapons-grade Pu that the United States stockpiled in Japan decades ago for some poorly-understood reason. Japan agreed in March to return that Pu which is a good thing and should have calmed China’s fears. Japan still has more than 44 tons of Pu, more than any non-weapons state possesses, but that will also leave soon.
On Monday, a spokeswoman for the Chinese Ministry of Foreign Affairs said that Japan’s stockpiling of nuclear materials was “a matter of grave concern for the international community” and questioned of whether Japan’s failure to disclose this material was unintentional or a deliberate concealment.
Japan’s storage of nuclear materials has always been a sore point to China who does fear that its historic rival will eventually break with its post-WWII policy of not developing nuclear weapons.
But Japan has only been pushing the use of plutonium in a recycling program because it’s essential to Japan energy independence. The Fukushima accident has raised questions about this strategy, but Japan has more MOX fuel fabrication facilities than anyone in the world except France. If Japan restarts its nuclear program, like it should, then they will need this material.
Otherwise, Japan might actually end up in a real war with China over the gas fields.
What is MOX?
MOX fuel is a way to blend recycled Pu and U from spent nuclear fuel into new fuel to get more energy out of the same amount of nuclear fuel while reducing the amount of spent fuel needing to be disposed. Adding a bit more plutonium to either used fuel or depleted uranium is relatively easy and cheaper than enriching uranium to higher levels of U-235. But you need to reprocess the spent fuel which can be expensive.
This is why using the existing stockpile of MOX Pu in Japan is so important. It’s already done and paid for, and Japan already has the MOX fuel fabrication plants. If Japan doesn’t use it, we’ll just have to dispose of it without the benefit of its enormous energy.
Today MOX is widely used in Europe and in Japan. Currently about 40 reactors in Europe (Belgium, Switzerland, Germany and France) and 10 in Japan are licensed to use MOX. France and Japan plan on using MOX in one third of its reactors in the near future, and Japan expects to start up its larger reactors as completely MOX. Other advanced light water reactors, including the EPR or AP1000, like being built in the U.S., are able to accept complete fuel loadings of MOX.
Using up to 50% MOX doesn’t change the operating characteristics of a reactor, just some slight adaptations. Burn-up of MOX fuel is about the same as that for regular fuel. As reactor operators seek to burn fuel harder and longer, MOX fuel becomes very attractive. In addition, reprocessing to separate plutonium for MOX becomes more economic as U prices rise. With respect to the waste, seven traditional fuel assemblies give rise to one MOX assembly plus some vitrified high-level waste, resulting in only a third of the volume, mass and cost of disposal as normal fuel.
Fast neutron reactors allow multiple reuse of Pu since all transuranic elements are fissionable, but in traditional thermal reactors isotopic degradation limits the number of times Pu can be recycled so most used MOX fuel is stored awaiting use in future fast reactors.
MOX is used now in some fast reactors in France and Russia. Russia leads the way in fast reactor development and is designing a new fleet of fast reactors fuelled entirely by MOX. The world’s largest fast reactor, under construction at Beloyarsk in the Urals, is set to start up at any moment.