This Molten Salt Reactor EATS Nuclear Waste

the cost of nuclear power plants is high because it is risky and most people think of it as a death machine plus companies have to deal with building delays design revisions and changes in the political landscape so when they ask someone for financing they're quoted a higher rate than for other power generation plans even if there are no delays nuclear power plants are more complicated to build so they take longer to start operating which means you pay a ton of interest before getting to revenue all in all a bad proposition unless you can lower the costs you can do this by making it safe enough that onerous safety measures don't need to be built in or you can reduce the cost of nuclear fuel or you can make it modular so you don't have to construct everything on the site but set up a factory that can manufacture components that can easily be shipped by road to the site elysium industries says that they can accomplish all of this uranium-235 likes fissioning well enough it decays into two smaller fission products releasing three neutrons those neutrons usually drift away decaying into protons but sometimes they can hit other uranium 235 atoms causing them to fission too luckily this doesn't happen very often in regular uranium or the world would be a lot more explodey this is because 99.3 percent of uranium is in the form of non-fissile uranium-238 only 0.7 percent is uranium-235 so if you want a chain reaction you have to increase the percentage of uranium-235 making it more likely that a neutron will hit an atom this is called enrichment and is accomplished by centrifuges that spin around so that the heavier isotope moves towards the periphery and the lighter isotope remains in the center all this comes together in a nuclear bomb conventional chemical explosives detonate compressing 90 percent enriched uranium fuel the density of the atoms increases and a chain reaction is triggered culminating in the ominous mushroom cloud this absolutely cannot happen in a nuclear reactor why because the reactor fuel is only enriched to five percent so the laws of physics preclude a nuclear explosion from happening but we've all seen the videos from fukushima what exploded there the answer is water more precisely it was a hydrogen explosion that was caused when steam came in contact with the zirconium fuel tubes water is very useful we can drink it bathe in it it helps slow down neutrons so they become more likely to hit other uranium 235 atoms it carries the heat from the reactor vessel and generates steam as an offering to the turbine fairy the problem well the first one is that it tends to absorb neutrons if average number of neutrons per fission go below 1 that means you no longer have a chain reaction that's why if you want to use fuel without enrichment you have to use heavy water which already has an extra neutron so it doesn't want to take one more on board most reactors used today are pressurized water reactors why pressurized because water boils at 100 degree celsius and we can't use it to create steam unless it's pressurized under high pressure you can heat water up to 300 degree celsius while maintaining it in a liquid phase and by running it over regular water we can generate steam but these high pressures mean in case of failure if the pump stops working and we lose pressure the water turns into steam instantaneously this can cause an explosion and while it may not be a nuclear explosion it can still disperse radioactive material into the environment you have the containment buildings to guard against that but you'll still end up with an expensive reactor that is now ruined now this doesn't happen very often and when it has happened it hasn't led to too many deaths chernobyl did have debts but far far fewer than the popular tv series implies remember that particular plant did not have a containment building something that would never happen today regardless as long as there is water near your reactor you'll always have that element of risk so what is the solution then elysium believes that by using molten salt they can do away with a lot of these issues molten salt is liquid up to very high temperatures so we don't need to pressurize it no pressure means no explosion which means you don't have to design your whole plant around the possibility of an explosion which automatically means lower costs molten salts also have a high negative temperature coefficient of reactivity this means that at the rate of fission increases and the temperature goes up the reactivity of the fuel goes down this is perfectly splendid because you can't have uncontrolled thermal runaway most molten salt designs tend to focus on thermal spectrum neutrons which means you need a moderator usually graphite to slow the neutrons from the fission process but these tend to expand and contract because of neutron radiation and are affected by the high temperatures of the molten salt for this reason they have to be changed every few years elysium tackles this by having a reactor that works in the fast spectrum that means their neutrons are not slowed down their energies remain centered around one mega electron volt you also get more neutrons with every fission in the fast spectrum so why doesn't everyone use fast reactors you ask why go through the difficulty of slowing down the neutrons if you can avoid it the answer is that the probability of a neutron splitting a nucleus decreases at higher energies this is partially offset by the higher number of neutrons but you also need higher levels of enrichment to get the chain reaction going after it starts though the extra neutrons can transmute the non-fissile uranium-238 into plutonium-239 which readily undergoes fission releasing a lot of neutrons in the process giving you a reactor that produces its own fuel that do from stuff like spent nuclear waste from today's reactors which we currently pay to get rid of another thing we want to be rid of is weapons great plutonium and this can be used as a starting fuel for this reactor they process all of this using a japanese technology to turn the oxides of uranium and plutonium into chlorides the elysium design is not modular like new scale has reactor heat exchangers all in the same unit they just have a steel can filled with enough fuel to go critical at 600 degrees this always remains the same on top of that you add heat exchangers and pumps you can scale it from 50 megawatts to 2 gigawatts based on the configuration you need so wait what happens if you add another heat exchanger on the vessel and draw more heat from the reactor the fuel should cool down right and as it cools the reactivity will increase which means the rate of fission will increase the more heat you draw the faster the fuel will be consumed this means that even without any intervention it can follow the demand coming in from the grid passive load following which is huge because this means it can be used with renewables and because of the fact that you're getting paid for the fuel rather than paying for it you can operate at a lower capacity factor without becoming uneconomical it is possible to start off with a lower configuration and scale it up as you go the regulatory processes will also be much easier to navigate for an upgrade as opposed to looking to build a plant from scratch the individual components are small enough to be manufactured in a factory and all of them can be transported by road this reactor operates at 600 degrees celsius they could go higher but operating at 600 degrees has the advantage of having qualified materials already no additional regulatory process required [Music] but syrah you say what about fission products the uranium or plutonium nuclei will decay into smaller fission products what are you going to do with those and if i'm not wrong xenon 135 gas is one of the common fission products which absorbs neutrons and this will kill the fission chain reaction well convenient question asking person remember the fuel is in a liquid state and what happens to gases in a liquid that's right they bubble out they can sit around for a few hours until they decay into something less grubby when it comes to neutrons because this is a fast reactor you can let the fission products just sit there for 40 years they won't ruin the reaction because you have an abundance of neutrons in the system it's the long-lived actinites that you have to look out for these are formed by chains of neutron absorption and beta decays and eventually the actinides stop absorbing neutrons and start fissioning so instead of being an intractable problem they become fuel let's talk about some of the things you can do with this thermal energy you can boil water and run a steam turbine you can use it to generate supercritical co2 and run a gas turbine which is much more efficient you can use it to store energy in molten salts or to generate hydrogen or even to heat homes another benefit of molten salt is that it is much easier to do chemistry on liquid stuff so you can extract all manner of useful medical isotopes things that help in diagnosis as well as curing cancer you have a lot of neutrons in here because of the high number of neutrons per fission so you can even breed new fuel by putting uranium-238 or thorium-232 in a blanket around the vessel they'll convert into fissile material you turn them into chloride salts with the japanese process and feed them into the reactor elysium is not focused on that right now because they want to eat up nuclear material not create more of it but it is something you can do fuel more and more reactors with stuff you make here so the next question you may ask is that's all cool but where are they at the big hurdles that they've hurdled are some alphabet agency has approved their fuel manufacturing process the one that uses spent nuclear waste to create the molten salt fuel for their reactor they're working with argon national lab to create a 10 megawatts thermal plant to check their design then they will look to establish a supply of raw material and get regulatory approval after all that by 2028 they may be able to start building full-scale nuclear plants here are some promotional images for wind and solar you can almost hear the birds chirping in joy and smell the perfectly manicured grass and here's a nuclear reactor this kind of architecture has to go make something that people are happy to have in their neighborhoods not these edifices to brutalism popularizers of nuclear technology shouldn't wait around for humans to start being rational give them something to like and then they'll do the work required to understand it people are smart when they're interested in something they won't know the name of their local politician but have every obscure batsman's averages and strike rates down pat so thanks for coming to my ted talk i've been thinking of making more videos on the next-gen reactor designs is there something you guys specifically want us to do the lifters of kirk sorensen maybe let me know in the comments below i hope you guys enjoyed this video like subscribe and start a conversation below to get more videos like this in your recommendations i'll see you really soon bye [Music] you

Channel: Tech for Luddites

Views: 497,154

Rating: 4.8864965 out of 5

Keywords: elysium industries, molten salt reactor, nuclear waste, ed pheil, elysium's new reactor, radioactive waste

Id: C6BGLgJY0Wg

Length: 12min 44sec (764 seconds)

Published: Sun Jan 17 2021

Reddit Comments

[u/feldomatic]

Hands down the most simultaneously informative and entertaining video on something NPP related I've ever seen.

Skip to around 50% if you already know the basics of fission to get to the details on the Elysium plant.

[u/Choclocklate]

Yes say welcome to the 4th gen nuclear reactors that either can use old fuel to produce energy with actinides (burner), use Plutonium, or can surgenerate their combustible from U235.

[u/Nescio224]

Exellent video, much better than what you usually find on youtube.

[u/gordonmcdowell]

Nice to see fresh take on YouTube nuclear comms.

[u/Sir_Amazing_63]

Wow. Its almost as though 95% of nuclear waste wasn't waste in the first place. (for the American nuclear fuel supply chain)

[u/hypercomms2001]

I initially thought the presenter was taking the piss....

[u/scaryjello1]

sounds like https://youtu.be/ss2hULhXf04