SoylentNews is people
SoylentNews
China prepares to test thorium-fuelled nuclear reactor
Scientists are excited about an experimental nuclear reactor using thorium as fuel, which is about to begin tests in China. Although this radioactive element has been trialled in reactors before, experts say that China is the first to have a shot at commercializing the technology.
The reactor is unusual in that it has molten salts circulating inside it instead of water. It has the potential to produce nuclear energy that is relatively safe and cheap, while also generating a much smaller amount of very long-lived radioactive waste than conventional reactors.
Construction of the experimental thorium reactor in Wuwei, on the outskirts of the Gobi Desert, was due to be completed by the end of August — with trial runs scheduled for this month, according to the government of Gansu province.
[...] When China switches on its experimental reactor, it will be the first molten-salt reactor operating since 1969, when US researchers at the Oak Ridge National Laboratory in Tennessee shut theirs down. And it will be the first molten-salt reactor to be fuelled by thorium. Researchers who have collaborated with SINAP say the Chinese design copies that of Oak Ridge, but improves on it by calling on decades of innovation in manufacturing, materials and instrumentation.
(Score: 0) by Anonymous Coward on Sunday September 19 2021, @01:08PM (20 children)
I would be happy if America just built modern uranium reactors.
The technology works, and the new designs are far safer--not that the old ones in America ever resulted in any serious accidents. There is no need for anything other than to build the damn things.
(Score: 2, Informative) by Anonymous Coward on Sunday September 19 2021, @02:34PM (4 children)
There are few...
https://en.wikipedia.org/wiki/Nuclear_and_radiation_accidents_and_incidents [wikipedia.org]
You may want to read up on first.
(Score: 5, Insightful) by sjames on Monday September 20 2021, @12:22AM (3 children)
Your list shows 7 fatalities in a nuclear plant in the U.S. for the entire history of nuclear power. We've had single accidents in coal mines that killed more than that (not to mention an entire town condemned as uninhabitable).
We've had a few more from weapons research, but still not enough to add up to one coal mining accident. At the same time, 4 of those 7 were due to a steam pipe in the secondary loop bursting, so could have happened at any steam turbine plant.
(Score: 2) by DeathMonkey on Monday September 20 2021, @06:25PM (2 children)
Hell, there have likely been more RADIATION [scientificamerican.com] deaths from coal than from nuclear.
However, being better than the single most harmful fuel on the planet doesn't necessarily make you good!
(Score: 2) by sjames on Monday September 20 2021, @08:51PM (1 child)
Yes, the radiation is more of a problem with coal where it is completely unregulated to this day. If someone somehow moved a fly-ash pile from a coal plant to a nuclear plant overnight, regulators would be calling out the National Guard to cordon off the radiation leak. Meanwhile, the coal plant is allowed to SELL the fly ash for use in building materials. And that's just the radiological hazard.
As for other fossil energy, there have been plenty of accidents resulting in fatalities over the years and entire regions facing ecological devastation due to spills.
(Score: 2) by DeathMonkey on Monday September 20 2021, @09:17PM
And there's over 1,400 of them in the US!
(Score: 1, Insightful) by Anonymous Coward on Sunday September 19 2021, @03:08PM (12 children)
And figure out storage. STILL. Come on, brah, if it's so easy...
(Score: 4, Insightful) by HiThere on Sunday September 19 2021, @03:31PM (11 children)
Evaporate the waste to a dry solid and sinter them into glass blocks. Then use them for low quality/long lasting process heat. Perhaps cover the glass bricks with a layer of lead impregnated glass if you deem that necessary, but if probably isn't for most uses.
It really *is* easy. The really long lasting "wastes" are so low in radioactivity that they're not much more of a problem than granite is. Most people are just scared stupid.
My objection to building more of nuclear plants is that we aren't *doing* anything to handle the wastes. That and cost-cutting management that makes really short-sighted decisions for short term profit taking. And that we allow the companies to be dissolved to avoid paying for decommissioning the plants. And a few other management issues.
Technically nuclear fission plants could be a very good idea. The implementation, though, leaves a lot to be desired. If Fukushima had been properly designed, rather than taking some stupid cost cutting measures, there wouldn't have been a significant problem. But the backup power supply wasn't located uphill, as it should have been. There were a few other problems, but they weren't technical in nature. (Well, of *course* there were technical problems. But they wouldn't have lead to a disaster noticed around the world.)
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 1, Touché) by Anonymous Coward on Sunday September 19 2021, @03:35PM
Cool, so it sounds like it's ready to go. Thanks for your hard work explaining that.
(Score: 2) by JoeMerchant on Sunday September 19 2021, @05:18PM (2 children)
Denial is more profitable than educating the public sufficiently to get approval to operate.
We have a strong tolerance for things that are already built and in operation, but an even stronger irrational aversion to accepting new things like nuclear waste processing in our "backyard". Little wonder with government's track record of secrets and lies.
🌻🌻 [google.com]
(Score: 4, Touché) by Anonymous Coward on Sunday September 19 2021, @08:22PM (1 child)
> Little wonder with government's track record of secrets and lies.
Let's leave it to for-profit corporations which have squeaky clean record on spontaneously looking after the environment.
(Score: 0) by Anonymous Coward on Monday September 20 2021, @02:56AM
Somehow, the media multinationals pushing the Die-for-Environment!!! agenda, are for-profit corporations too.
It is a sad state of the humanity, when peddling fear is far more profitable than making any real goods.
(Score: 5, Insightful) by RS3 on Sunday September 19 2021, @08:31PM (2 children)
I do some work for a small company where I make, test, repair, etc., some instrumentation for nuclear reactors. The instruments work and are reliable, but could (have) use(d) some design refinements, especially where parts are obsolete and I'm having difficulty finding NOS (New Old Stock) parts. But I'm not allowed to change anything at all. It's crazy expensive and time-consuming to attempt to get anything re-certified for a nuke. Pretty much the opposite of agile development. And I'm not saying to take risks, rather make a more streamlined process. For instance, changing a resistor value does not need new radiation bombardment tests. Well, you could argue to do it, but it really doesn't need all of the dozens of tests repeated. Heck, electronic component variation could effect the outcomes just as much.
(Score: 5, Interesting) by corey on Sunday September 19 2021, @11:34PM (1 child)
I’m doing some work in space electronics, what you say resonates. But lately what’s been the trend in space electronics is, rather than make sure every IC is rad hardened, more COTS components are used with a risk based approach. That is, include various mitigations such as TMR (redundancy), reconfiguring FPGAs occasionally (and only configuring then when you need), etc. The cost comes down heaps, and I think the regulators are on board with it. I guess similar issues would be encountered with nuke electronics like total dose, SEE (SEU, SEL), etc. when exposed to charged particles.
(Score: 2) by RS3 on Monday September 20 2021, @07:46AM
Oh wow, FPGA in space? Okay. I'd have thought they'd lose a bit here and there and then you're hosed.
The nuke stuff I work on doesn't get individually rad tested. Initial / test units did, and the assumption is if they're made exactly the same, they'll be okay. And there were huge margins so I'm not worried. But thinking you can get the exact same part with the exact same characteristics 30 years later is unrealistic. But again, I'm not allowed to change or substitute so I do my best to replicate the antiques.
These handle space rad better: https://www.science.org/content/article/return-vacuum-tube-rev2 [science.org]
:)
(Score: 4, Interesting) by deimtee on Monday September 20 2021, @01:02AM (1 child)
Not glass blocks, they can leach. CSIRO / ANU figured it out decades ago. You incorporate it into Synroc [wikipedia.org] and stack it in a desert.
If you cough while drinking cheap red wine it really cleans out your sinuses.
(Score: 3, Informative) by HiThere on Monday September 20 2021, @03:34AM
No. That's wasteful. Synrock is ok, but you don't need that. Glass blocks are fine, you just put a second layer of glass around the inner one. And you want to use them as a heat source, not just pile them out in the desert. If you want to make them into Synrock, well, OK, but you may need to sheathe it anyway, because you want a smooth external surface. And I don't think it's needed. (You didn't include a trademark notation, but it sounds as if one is supposed to be there.)
The thing is, you don't need to guard it for thousands of years, because the really radioactive things have short half lives. So if a small amount leaches out in a century of so it doesn't matter. But if you want to protect against that, at least use it for low level heat while it's still hot.
P.S.: That "second layer of glass" is probably sufficient, but you may want it to be lead glass or some such. It depends on the nature of the stuff on the inside...and that stuff has already been mixed with a bunch of sand, because I didn't just mean glassified nuclear wastes, I meant glass. If you think it necessary (I don't, but I'm not a real expert) you could have a layer of heavy oil or tar between the outer block and the inner one. That will keep any water from penetrating in case there's a leak in the outer layer.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 2) by PinkyGigglebrain on Monday September 20 2021, @04:19AM (1 child)
I hate to break this to you but the waste IS a solid already. It just has to be kept in pools of water to keep it from melting and/or combusting on contact with air.
How ever, as the fuel rods are actually 96% reusable U-238 and 1% Plutonium that can be used directly as fuel again once the fuel rod is recycled the remaining 3% of the old rod that is actually unusable* in a nuclear reactor could be sintered into a ceramic that could possible be used in applications where you needed a constant low yield heat source, like a desalinization plant that uses reduced air pressure to lower the boiling point of the water. Similar to an OTEC [wikipedia.org] system.
A ceramic would be better since they can be made to withstand more thermal variation than glass before shattering or maybe something like Borosilicate glass, aka, Pyrex.
*fission byproducts, whats left over when the U-235 or Pu atoms get split. mostly neutron absorbing isotopes that "poison" the chain reaction They produce all the heat as they decay.
"Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
(Score: 2) by HiThere on Monday September 20 2021, @01:49PM
IIUC, there are multiple steams of waste, and it isn't all solid.
And to be even more "nitpicky", the proposal I mentioned wouldn't handle gaseous waste, like tritium or various other isotopes of this and that, so provision would need to be made for them. But it's not really difficult. There shouldn't be that much, so really minute porous inclusions should suffice. (I don't think there are many elements that would be liquid at the likely temperature, though gallium comes to mind and there are a few others, but I don't see them as causing a real problem.)
OTOH, to convert the stuff into glass bricks you'll need to raise it to the melting point of glass. (Any old waste glass should do for this purpose.) Then you mix it in and let it slowly cool (just a bit) before you add another clean layer of glass or so. (If you need to get really fancy, you could sculpt out a hole in a larger glass brick, add some tar, and then place the layered glass brick inside the large one and seal it. Naturally it's trickier than that, but the basic process is simple, relatively cheap, and yields a source of low level heat.
But if you think you need to foam the inner block slightly things get more complicated. I think it would still be relatively cheap and easy, though, once you had the process set up.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 5, Informative) by PinkyGigglebrain on Monday September 20 2021, @02:28AM (1 child)
I'm sorry, the modern Uranium rectors in the USA are not nearly as safe as they are advertised to be. They still use normal water under extraordinarily high pressures to cool a mass of solid fuel that would happily continue to undergo fission even if the coolant was lost. As has happened several times in the past, Three Mile Island, Chernobyl, Fukushima, and several other smaller incidents with rectors aboard modern military vessels that didn't make it into the main news channels.
All of the commercial, and military, plants currently operating in the USA are all Light Water Reactors, meaning they use normal water to both cool the core and transfer the heat to where it can be used.
Now the problem with those reactors is that to get enough heat out of the core to be useful you have to have temperatures way over the normal boiling point of water. So to keep the coolant from turning to steam the cores have to be kept under a lot of pressure, around 2300psi. ( For context a SCUBA tank is usually at 2000psi.) and if there is even a small leak in the system the coolant goes almost instantly to steam and the core can over heat and all sorts of bad things happen. Kind of like when you pop the cap on a cars radiator when the engine is hot.
Once the water has boiled away the solid fuel in the core keeps getting hotter until it melts into an amorphous mass like what is currently sitting ind side the rubble at Chernobyl.and Fukushima that can continue to undergo a self sustaining chain reaction.
Where Molten salts have the huge advantage is that since the salts, which are both fuel and coolant, don't need to be under any pressure to remain a liquid at normal operating temperatures the core is at near ambient pressure. So no danger of a massive steam burst blowing your building up.
Another lovely feature of a MSR is that as the fuel/coolant heats up it expands, moving the fissionable atoms further apart and reducing the chain reaction. It self regulates. Once it reaches operating temperature you have to start cooling it to keep the reaction going.
Where MSRs really shine however is that because a chain reaction needs a specific volume, aka critical mass, to keep going. If the fuel gets spread out too much the reaction stops and the fuel cools and solidifies. So if the core did get cracked open somehow, say a plan hit it, the fuel would no longer have critical mass and the whole mess passivley shuts off and contains itself. Which allows for a wonderful safety feature in the reactor. To shut it off all you have to do is drain the core into a holding tank that doesn't maintain critical mass, and the plug on that drain can be nothing more than a bit of the fuel salts kept cool by fan cooling the pipe. If you lose power the fan stops cooling, the fuel gets hot and melts, the core drains into the holding tanks and the chain reaction shuts off. Literally walk away safe. I've heard that the MSR test reactors at Oak Ridge would occasionally be shut down at the end of the week by just turning off the freeze plug cooling and letting the core drain out. So that trick has been tested and proven.
tldr: Watch Liquid Fluoride Thorium Reactors [youtube.com] It covers everything about MSRs and Thorium you need to know to understand what China has accomplished.
"Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
(Score: 0) by Anonymous Coward on Tuesday September 21 2021, @12:14PM
I agree about pressurized water reactors being the height of stupidity. I'm just gonna nitpick you on the 'would happily continue to fission' thing.
See, it's that ~6% of the rated heat load of the reactor comes from the daughter nucleides tumbling down their decay chains, and those start out more or less distributed across the periodic table (it's actually a bimodal distribution, because U235 doesn't tend to split equally very much).
It's not fission that makes an uncooled reactor melt down, it's the intense radioactivity of a mess of freshly shattered atoms that does it. And it takes months to fade.
Seriously though - building a fission reactor with solid fuel (meaning it can only be removed mechanically piece by piece, IF the pieces haven't been damaged...) AND putting that thing into a pressure vessel, and then cooling it with water (bad choice). And on top of that, cladding that solid fuel in a material which will catalytically crack water into hydrogen and oxygen gas at high temperatures.... Got to be the dumbest possible reactor design I can think of.
Only one worse is running a fast-breeder reactor. Although I kind of feel that molten sodium metal is actually a better choice of coolant than water, steam-pressure-vessel-bomb-hazard considered. And the fact that it burst into violent flames on contact in air could be considered a bonus - at least you aren't going to ignore slow leaks. Problem with fast breeders is that if maliciously controlled - or just out of control, a-la Chernobyl, well... They need to have very concentrated/large fissionable inventories to work at all, so 'the worst that could happen' tends to be pretty bad, especially compared to thermal-spectrum. Luckily we haven't seen that 'worst' yet, and I hope we never do.
But I would be much happier with a nearly-intrinsically-safe* molten-salt reactor.
(* you know, apart from all the heat and neutrons and radioactivity, that is).
The way I like to think of it: Adam Savage of Mythbusters fame said the most impressive explosion, to him, was the one caused by an electric water heater. That's a pressure vessel, with water in it, closed off, and having too much heat applied. They had to strip out and override at least three different very simple and reliable safety devices to get it to explode, but when it finally did...
When the guy whose name is listed as an inventor on the patent for light water reactors pleaded with congress to ban them, well, who would know better?
But hey, 'better the devil you know', right? Except it turns out that is really just stupidity caused by FUD.