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Debunking some of the myths around thorium

An experiment on the thorium reactor with molten salts and some myths about thorium reactors, Actualité Houssenia Writing , by: Jacqueline Charpentier, August 26, 2017  An experiment in the Netherlands will test the design of a thorium reactor with molten salts. Beyond the announcement, we take advantage to debunk some myths around the thorium reactor.”………

Myths about the thorium reactor

Since uranium has a very bad reputation, there have been a lot of myths circulating on the thorium reactor:

1 Some have argued that thorium might be so interesting that it would surpass nuclear fusion Its promises by cons). We used information from the Whatisnuclear site whose authors are mainly engineers and nuclear physicists to clarify the myths around thorium.

2 This is deceptive. The thorium reactor can make bombs and this is not what motivated its cancellation at the beginning of the development of nuclear reactors. The conclusion at the time was that even if the thorium reactor could be cheaper, its performance over the long term is unknown.

In addition, the industry had already invested heavily on light water reactors, very high temperature reactors and the fast liquid metal reactor. The industry was also reluctant to create services for the fuel cycle and research in nuclear physics had focused heavily on solid fuel reactors. Basically, the world had invested too much in the uranium reactors, throwing it all into the trash and choosing thorium, because it was not worth it.

Thorium reactors do not require enrichment It is a misunderstanding of the concept of a reactor with a fast breeder, whether based on thorium or uranium. The principle of this type of reactor is that they will breed as they go. They will produce fissile material equal to or greater than their initial consumption, which will provide an abundance of energy over the long term. So we can say that this is not a true myth, but the lack of enrichment is valid for all types of breeder reactors. That’s why we invented them. However, the thorium reactor can use thermal breeding. This means that much fewer fissile materials are needed initially than a fast breeder reactor. But the fast reactor with liquid metal can do the same thing and therefore, it is not exclusive to thorium.

“The thorium reactor can not produce nuclear bombs”

This is probably the myth that comes up most often. And that’s not true. The thorium reactor operates by regenerating Thorium-232 through Protactinium-233 which produces uranium-233. And uranium-233 is fissile. The process is more difficult, but it is theoretically possible. However, another common myth is that you can have a bomb as soon as you have a civilian nuclear reactor.

Obtaining a fuel for a bomb is so complicated in any civilian nuclear reactor that it is almost impossible. But since the proliferation of bombs is a serious problem, we will still use the precautionary principle. But whether it is for a uranium or thorium reactor, a bomb is always possible … in theory.

 There is more thorium than uranium on Earth

That’s true, but you have to qualify. The mean concentration of thorium in the earth’s crust is 0.00060% compared to 0.00018%. But we also have thorium and uranium in the ocean. For a percentage by mass, there is 4 × 10-12% thorium compared to 3.3 × 10-7% uranium. In figures, this gives us 56,000 tons of thorium and 4.62 billion tons of uranium. However, the exploitation of uranium at sea costs 4 times more expensive and therefore it is not economically viable. Therefore, this myth is true if one relies solely on concentration in the earth’s crust.

But the distribution of deposits must be taken into account. India has no exploitable uranium deposits, but it is sitting on tons of thorium. China has 50% of thorium compared to uranium. So yes, the thorium reactor is very interesting for these countries because they do not need to go and get uranium on the other side of the world by corrupting local governments in passing.
 
“The waste from the Thorium reactor lasts only a few centuries”

We also hear this myth. Compared to the uranium degradation cycle over thousands of years, waste from the thorium reactor would last only a few centuries. It is true that the thorium reactor produces only a few transuranic elements. Transuranic elements such as Neptunium, Plutonium, Americium and Curium are the most dangerous nuclides in a period of 10,000 years. The problem is that uranium reactors such as fast neutron reactors also produce few transuranic elements. So yes, the thorium reactor produces less harmful waste in the long term, but it is not the only one.

Attention is not neglected to the interest of the thorium reactor, but it is not the ideal solution proposed to us by some players in the industry. For some countries such as China and India, thorium could be a real alternative, because they have a large amount in front of their doorstep, but globally it is more complicated.

And if one day the uranium mining at sea becomes economically viable, then thorium is likely to take a big hit because of the colossal amount of uranium in the ocean compared to thorium.

August 31, 2017 Posted by Christina Macpherson | France, thorium | Leave a comment