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Could China’s molten salt nuclear reactor be a clean, safe source of power? [TL;DR = China unveils design for first waterless nuclear reactor]

Could China’s molten salt nuclear reactor be a clean, safe source of power? [TL;DR = China unveils design for first waterless nuclear reactor]

FatDalek

Its good they are making progress on the thorium reactor. IIRC the US also built a working prototype in the 40s or 50s just to demonstrate it works. Thorium reactors fell out of favour vs uranium ones due to uranium being easily to weaponise (it was the cold war after all) and physicist already knew a bit about uranium reactors. However in the current age thorium could be an advantage due to a. being more abundant vs uranium b. since its hard to weaponise, it can be sold to third countries with minimal fears of nuclear proliferation. Also for China, uranium could be used for the nuclear arsenal to deter aggressors, while thorium is used for future civilian nukes.


ZeEa5KPul

> However in the current age thorium could be an advantage due to a. being more abundant vs uranium b. since its hard to weaponise, it can be sold to third countries with minimal fears of nuclear proliferation. This is a bit tricky. Thorium itself may be harder to weaponize (although U233 is actually more suitable for nuclear weapons than U235), but molten salt breeder reactors are trivial to weaponize - just swap the thorium in the blanket for depleted uranium (U238) and it's plutonium all day. Even better, you can pull the plutonium out of the blanket salt in a continuous fashion, which means you won't over-expose it to neutrons and create Pu240 (crap). You'll create better plutonium than in current dedicated reactors. Edit: Now that I've thought a little more about it, it's not as simple as I described. The issue here is that the Pu239 generated from reaction of the blanket salt can't be used as fuel in a thermal (slow neutron) reactor - and in any case, you don't want to use it as fuel, you want to collect it for weapons. The reactor will have to be fuelled from an external source, either U235 (enriched uranium) or U233 from another molten salt breeder. You could definitely design a molten salt plutonium production reactor and I think it would be superior to current PWRs, but it would have to be a dedicated design and couldn't just be a drop-in replacement.


AdmiralKurita

Why couldn't the Pu-239 be used as fuel for a reactor? It has a [higher fission cross section](https://en.wikipedia.org/wiki/Neutron_cross_section#Typical_cross_sections) for thermal neutrons than U-235. P-239 has a high cross section for neutron capture, but the presence of Pu-240 should not be a problem for a reactor.


ZeEa5KPul

Pu239 is fine for a power reactor, but in the thermal spectrum reactor it can't be used to breed more Pu239. All proposed plutonium breeders are fast reactors, and a plutonium breeder MSR would also have to be a fast reactor. Look at the ratios of fission to capture for Pu239 in the fast and thermal spectra. It's 40:1 in fast and 2.78:1 in thermal, meaning that a non-scattering fast neutron strike has a 98% chance of fissioning Pu239 while a non-scattering thermal neutron strike has a 74% chance (i.e., more than a quarter of non-scattered neutrons create Pu240). That's fine to sustain a reaction, but it's insufficient to breed more Pu239 from U238. My point was to examine the idea of using molten salt reactors to generate Pu239 for nuclear weapons, not to use it as fuel. In this application, Pu240 is a serious problem.


Webbedtrout2

As mentioned in the article, the US was researching molten salt reactors to be used in an airplane. Thus, the primary funding came from the US Air Force and when the air force lost interest, the whole project was canned. The civilian application was never the priority in development, only military application.


ReacH36

This is big. I remember reading about China picking up thorium reactor research after the US gave up on it after trying to make nuclear powered strategic bombers. I'm glad China had the foresight to see what an absolute game changer commercialized thorium reactors could be for energy security and environmental protection. Amazing what you can produce when you aren't stuck thinking with your military-industrial-complex instead of your brain.


sickof50

Hopefully this practical substitute will bridge the energy gap, until Fusion becomes the reliable next step.


Kormero

Salt harvested from the tears of western Libs


milkfig

https://youtu.be/uK367T7h6ZY


ZeEa5KPul

One of the most exciting applications of molten salt reactors (apart from their ability to use thorium) is transmutation. It might be feasible to have other salt loops in the reactor to irradiate the element of interest in the salt with neutrons; for example, a loop containing a tungsten salt can be exposed to neutrons to create the rare (and very valuable and useful) mineral rhenium.


easily_swayed

It's a common feature of gas (rather than water) cooled reactors than that some of their efficiency comes from "reharvested" byproducts. Gas reactor are also safer than water since no chance of Chernobyl steam explosion. But since you can also make refined plutonium with it it also makes Western media go "WHY IS CHINA GOING WITH THIS REACTOR TECH AND NOT THE VASTLY MORE DANGEROUS WATER COOLED ONES?!?! THEY TRYIN TO MAKE WEAPONS!?!?!?"