Thorium Reactors Could Change Energy Forever – Unlike uranium, thorium is way safer, more abundant, you can’t make a bomb out of it, and produces less nuclear waste. Some countries (India & France) are already testing thorium reactors as a clean energy solution.
Original article: and many ridiculous or confused reactions, on https://www.facebook.com/sciencedump/posts/pfbid0bc9AWgk7Me7KrUMXEv8mkHFca2QtzgBLU56AAiBiVw2T7Dzt8oVKZidDmVMZRTual
Several Things Unclear in the Post and Comments
So many people commenting are not clear whether they are talking about Thorium in a solid-fueled water-cooled reactor similar to a Light Water Reactor (the most common nuclear reactor in USA and Europe), or Thorium in a molten-fueled salt-cooled reactor.
If you don’t stay clear what reactor you are talking about, you will say things that are wrong, incomplete, inconsistent, confusing, or lies.
Thorium for Nuclear Waste Reduction
Thorium is about the same as uranium for radioactive waste (Th –> U233 in the reactor, instead of uranium enrichment increasing U235, similar fission products). Thorium in a solid-fueled water-cooled reactor is little different than LWR for amount of “waste” uranium.
Thorium for “Making a Bomb”
Yes, you can make a bomb from U233, but it is so much harder to extract pure U233 from Molten Salt Reactor fuel than it is to make a dirty bomb from a 1940s method of putting uranium in a “graphite pile” to make plutonium, that nobody does it.
USA National Laboratories testing a bomb, laboriously made using full research reactors to produce enough U233, produced a dud. It is very expensive, very difficult (even for a National Laboratory), and not worthwhile.
People who know what they are doing would do the easier way; people who don’t know what they are doing would die from extreme radiation from U232.
Thorium vs MSR for Long-Term Nuclear Waste
“It produces less nuclear waste” is not from using Thorium, but rather from using a molten-fueled salt-cooled reactor, where over 99% of the fuel gets fissioned. (LWR fissions about 3% of the fuel.)
Some variants of Molten Salt Reactor would breed Thorium to Uranium233 for fuel; some variants of MSR would use “waste” LWR fuel. Simply shredding and melting the LWR fuel pellets and adding it to the MSR fuel salt, you can fission more than LWR could.
Where are Molten Salt Reactors being Built and Tested?
Talking about which country is developing new reactors, you have to specify what kind of reactor.
Again, Thorium in a solid fueled reactor is very different than Thorium in a Molten Salt Reactor. Most of the reactors built that used Thorium, were adding Thorium to LWR fuel pellets. Harder to keep the fission rate stable than in ordinary LWR fuel.
There are countries around the world doing research in materials, handling fission products, design of reactor components for easy maintenance, for easily replacing the parts that get the most radiation damage. Since MSR is at low pressure (“garden hose” pressure vs LWR kept to just below the pressure limits of the best-made steel pressure vessel), and since all MSR are extremely stable fission rate, robotic replacement of components is easier, without having to shut down the entire reactor.
MSR Safety
Molten Salt Reactors have much better safety than LWR, since the fission rate is inherently stable, and there is no possible “loss of coolant (water) accident”. There is no water to lose, in MSR.
Temperatures in MSR are always below the melting point of the reactor materials.
Temperatures inside LWR fuel pellets are always much higher, in an operating reactor, than the melting point of the reactor materials.
MSR can’t have a “core meltdown”, physically impossible to get the temperature high enough to melt the materials.
The most dangerous fission products in MSR get strongly chemically bound to the fuel salt. In LWR those fission products are simply carried in water, and get into food. In MSR, the salt cools to solid, can’t move out of the reactor building, doesn’t dissolve in water, doesn’t react to air, doesn’t have any chemically reactive elements (no explosions possible).
In MSR, those fission products are simply stored 1 to 10 years (depending on the element’s half-life), until they are below background levels of radiation, and can then be sold to industries that use them.
In MSR, cleanup after a “major accident” would be of a few cubic meters, not hundreds of square miles many yards deep. In MSR there is water only in the kitchen and bathrooms and yard, not in the reactor; no contaminated water to pollute the ground water. There is no high pressure to propel radiactive materials into the atmosphere.
In MSR, there is no high-pressure water containment building, since there is no water to contain and no high pressure. There is no exclusion zone where it isn’t safe to live.
When Will We Have Molten Salt Reactors?
When there is sufficient funding.
In the 1960s, a few scientists got one working, from beginning the design, to testing materials, to building a reactor, and turning it on, in 5 years. Scientists with slide rules.
They built and tested a small reactor. But there is nothing about MSR that makes it harder to make a 2GW reactor than to make a 100MW reactor.
Today, we have computer simulation of the fission and fuel flow through a reactor, to test different designs before making any. We have physically accurate modeling of the parts, how the parts work together, how the machines to assemble them work, how the equipment to maintain them work.
We’ll most likely have factory-produced 100MW reactors, easily shipped and installed anywhere they are needed, as many on a site as are needed. We will likely have “replacement reactors” swapped in for maintenance, since standardized small reactors can fit in a standard inter-modal container.
We can have an MSR flown to any disaster site in the world, for power and clean water.
A reactor site can be made from factory-assembled components (1 intermodal container for the reactor vessel, 1 for the cooling tanks, 1 for small electric generators, 1 for a small water desalination unit, 1 for a small heat + CO2 + H2O = gasoline converter, etc.).
Or, float pieces of a reactor site to the site, like large ships are built from multiple pre-assembled pieces. One MSR company has the manager of a large ship-building yard on their staff.
We just need the financing.
If the USA’s Nuclear Regulatory Commission doesn’t change their “for LWR” regulations, the first MSR will be tested in other countries.
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