Thorium cycle Thorium versus Coal Thorium is, as elsewhere mentioned, actually not radioactive. But by absorbing one of the neutrons, subsequently formed in the process, it will transform into an uranium isotope, which by itself is a useful fuel in nuclear reactors.
Beter than what is used today.

A reactor based on thorium must therefore be started with a temporary neutron source.

Click at pictures for full size

India, apparently, works on a further development where existing technology is being modified.
Using water as a moderator. – More later.

In China and other countries, another approach is followed.
Here, the thorium fuel is dissolved in molted salt.
Along with great benefits there are obviously new challenges.

Here it is necessary to go a little bit into details with the technical.
U235

  • Neutrons (the small blue on the sketch) are the “cornerstone” in all processes involving nuclear power.
  • BUT
    The neutrons that are formed in the core processes are fast – some
    10% of the speed of light – and must be slowed down (moderated) before they can carry the process forward.
  • Therefore a moderator is used.
    In almost all reactors this moderator is water.
    As with ordinary (coal-fired) power plants, the water will be under pressure.
  • At nuclear power plants this will require a strong containment to withstand pressure.
    This containment, that holds the nuclear reactions, is close to
    300 tonnes and is usually cast (pressed) in one piece.
    This, of course, is a major challenge, both technically and economically.

Sometimes we talk about “fast reactors”.
However, it is not the reactor that is fast but the neutrons that form part of the process that are fast – not moderated.
These reactors are different from ‘alt the other’ and should be cooled with liquid metal, eg. sodium.
Test Reactors can be found in many countries.
Although, for the time being, it is mostly a theoretical possibility, there are many indications that it will turn out to be the “energy source of the future”.

  • If the fuel is dissolved in molten salt and graphite is used as a moderator, the process does not have to be under pressure.
    Perhaps a weak vacuum.
    Thus, you can avoid the huge and expensive pressure vessel.

Neither thorium nor molten salt is something new. It has been tested several places successfully.
Although molten works well together with thorium, we should not forget that thorium can be used without molten salt and molten salt can be used without using thorium.

  • As we have got better understanding of the processes that underlie nuclear power and have got completely different computers, it is now possible to simulate a much better design.

Nixon
On Oak Ridge Laboratory in Tennessee,
a four-year trial ran without problems but
was stopped by Nixon.
It is alleged that he was more interested in nuclear bombs.

Atombombe Eksploderer

Countless articles in the media and at the internet provide long explanations and highlights the enormous advantages, while there are few objections.
Most speaking about the many and
long-term trials that will be necessary.

Of course, you also see the usual protests that testify to inability or lack of decier to communicate the facts.

Nuclear power utilizing thorium in connection with molten salt differs fundamentally from the well-known uranium utilization design.

  • As already mentioned, there will be no need to keep the nuclear processes under pressure.
    Besides saving, it will open up for many other benefits.
  • As the fuel is already liquid, there is no risk of a nuclear meltdown, which, although often trumped in the media, does not have to be a disaster.
  • On the other hand, reactors based on molten salt will be “naturally safe” and have “passive safety”.
    This means that there is no need, other than gravity, to let the fuel run down to a safe position in case of an overheating.
  • As mentioned elsewhere, known reserves of thorium are significantly larger than known reserves of uranium.
    This, along with the 100% utilization of thorium, means that there will be ample and cheap energy for thousands of years.
  • Not only will thorium-based reactors be more effective.
    They will also be able to utilize existing waste from uranium-based reactors.
  • If you have s look at the numbers and remember that, what is referred to as being waste, still contains aprox. 95% of the original energy.
    This waste, along with the depleted uranium that is also waiting for being used, will, along with what is certainly on its way, be able to deliver a lot of energy for perhaps hundreds of thousands of years.

Of course, new and expensive experimental facilities will be needed.
Perhaps most to find suitable materials and not so much to control the nuclear processes.
It has even been proposed to use ceramic materials.

Such a reactor should last for 60 years, as long as the known uranium based reactors.
Thus, it can not be ruled out that investors feel that large amounts have already been invested in developing uranium-based reactors and that NOW, finally, all the childhood disease have finally been overcome.
“What we have, this we know, it works well – There is cheap uranium for a few hundred years – why suddenly start something new?”

Nevertheless, the development has started to come.

Air pollution China - Far beyond the sea

  • In China, where air pollution reaches far beyond out to the ocean, one desperately needs pollution-free energy.
    In addition to a very comprehensive program for ‘traditional nuclear power’, new research, supported by Bil Gates, work is going on for a more advanced design with molten salt.
  • In Europe, it may have been seen that you can not continue with “just so” sit on your hands and wait.
    Apparently, one will try to pile the efforts together and work on a project based on Thorium in connection with liquid salt: SAMOFAR


In India there are large deposits of thorium and here you started using thorium in connection with the further development of known design.
Here a mixture of thorium and uranium is used in an existing reactor type that has been modified for the purpose.
Even though there is a long way to go before reaching a goal, one can believe that
the target is within range.
Of course, the devil is in the detail and apparently there are unbelievably many, almost unknown, details that need to be kept track of.
A link: “Introduction of Thorium in the Nuclear Fuel Cycle (2015)” with
133 pages give a terrifying impression.
In addition, there are countless patents that can not be circumvented.

In Norway you see smal steps forward.

Mr. Niels Bohr.jpg
In my country, Niels Bohr’s homeland, everything related to nuclear has been a naughty words.
Still work is going on to clarify opportunities and challenges associated with a modular construction of small reactors that can be manufactured centrally and ready assembled where deemed necessary.
This will mean that small reactors can become “off the shelf” that, after use, can return to the supplier for upgrading, recycling or landfill.
. Thorium er Fremtiden
There are good deposits of Thorium in Greenland and in Norway.
Therefore it is tempting to say that in Denmark we should go ahead and become a pioneer for cheap and pollution-free energy that does not depend on changing sun and wind.
HOWEVER
Especially in Denmark there has been built up public sentiment against nuclear power.
Although this resistance is based on extremely dubious arguments, it must be faced that, apart from importing electricity, nuclear power based on uranium will be a very long way off.
Thus, it would seem logical to wait until “the other” (China) has developed commercial use of thorium.

It is to be hoped that it will not last too long and that the “No No No people” do not succeed to ruin also this obvious opportunity for cheap and clean energy.

PostScript

This blog can only be seen as an addition to something else I’ve written with the aim of eliminating some of the erroneous “information” and tenacious myths that have arisen about nuclear power.
See http://wp.me/p1RKWc-cM

It has not been my intention to cover more than a minor part of the enormous opportunities opening up for the use of thorium in future energy supply.
As I in no way have more than ordinary skill in the area, I would be grateful for bug fixes and suggestions for changes.
Write to me at thorkilsoee@gmail.com

Yours impatiently waiting
Thorkil Søe.

Last words

A bit pessimistic, it is said that we write much but do too little.
AND
Of course, Greenpeace is busy explaining that it will never work.
Apparently, this link gives a good overview of the many challenges that are mentioned, most focusing on materials and chemistry.
A long and very thorough assessment can be found here.

Illustrated Science

As can be expected, there are interesting – and optimistic – articles in Illustrated Science.
– From REO’s archive: (No. 3 2012.)
– An “argumentative” and seemingly realistic article page 48 to 55 in
no. 13 2016: “T-Force yes thank you”

magi

The Future

A lot of research is going on in different countries.
Apparently to get closer to an understanding of the many challenges.
Click on the pictures below to get full size.

As already mentioned, we see many different proposals.
All hoping to come forward with the magic “Silver Bullet”.
The drawing to the left shows a Danish design.
The graph to the right will – hopefully – describe the development.

Thorium - DK.png

Udviklingsaser for Thorium

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