How This Rare Natural Fission Reactor Could Solve Our Nuclear Waste Problem

Controlling fission reactions in modern nuclear plants is a complicated and dangerous process, yet nature managed to do the same thing all by itself two million years ago. Here’s how.

Read More:
Ancient Nuclear Waste Is Teaching Us About Radioactive Storage Today
“To get data on what happens to spent nuclear fuel over long periods of time, researchers are turning to a unique place on Earth — the oldest, and only, known natural nuclear reactor.”

Meet Oklo, the Earth’s Two-billion-year-old only Known Natural Nuclear Reactor
“For such a phenomenon to have happened naturally, these uranium deposits in western Equatorial Africa must have had to contain a critical mass of U-235 to start the reaction. Back in those days, they did. A second contributing factor was that, for a nuclear chain reaction to happen and be maintained, there needed to be a moderator. In this case: water.”

The world's first and only natural nuclear reactor
“In a singular but well-documented circumstance, scientists have found evidence that naturally occurring fission reactors were created inside three uranium ore deposits in the west African country of Gabon.”

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[naners]

Moderators don't prevent meltdowns, they increase the neutron cross section, the likelihood that a neutron will interact with a target nucleus, and allow for more reactions to occur. The control rods are the main tool used to adjust the neutron flux to be self sustaining, known as critical, and not super-critical aka meltdown.

[Silanael]

Downvoted for wrong information. Moderator slows down neutrons to make fission EASIER, not to "prevent explosion". This allows the reactor to run on less-enriched fuel.

[cowswayne]

Well to be perfectly honest, in my humblest opinion, of course without offending anyone who would otherwise think differently from my own point of view, but also by looking into this matter in a different perspective and without being condemning or condescending to those opposed to one's view's, as well as considering each and everyone's unique and valid opinion, I honestly believe that I completely forgot what I was about to say.

[northernsmith]

Thorium reactors will burn our nuclear waste as a starting cycle. The waste can also be continually fed into a thorium reactor to completely use up the fuel.
A traditional reactor only uses 10-15% of the solid fuel before the rods are damaged beyond safe use do to Xeon gases produced durning the reaction.
We need to be pushing for thorium in the USA. China is well on its way to building a full size reactor.

[TommoCarroll]

Saw this coming millions of years ago with my 20/20 _fission_ .... 👀




Phwoar, that was a good'n!

[RIPPEDDRAGONk]

I was so happy to see this finally covered by a source that a lot of people see and then horrified at the incorrect information given. There is a BIG difference between a nuclear explosion from a bomb and a nuclear reactor melt down...

[stanleytolle]

In Molten Salt Ractor's the radioactive wastes bind to the salt coolent/fuel in a similar way as presented in this video. This would indicate that this type of reactor would be quite safe

[buny]

There is a lot more to learn from our Mother Nature

[pikesplitman]

2:00 error. The neutron absorption cross section is proportional to 1/v. The moderator is used to slow neutrons to increase the probability of absorption.

[abaeza]

I like the presentation on this. Very low energy and relaxed. A lot easier to binge

[hristiyankolev]

Around 4% / Not silver - Boron mainly in addition to Hafnium or Gadolinium

[garDre]

OR, we could use Thorium reactors which are safer, more efficient and will be cheaper once we sufficiently commit to them. But you know, sunken costs and special interests...

[aurorajones]

The thought of a natural reactor is so fascinating! That would be cool to see active in real life.

[MrCordycep]

To control the rate of a nuclear reaction, you use control rods made of materials that absorbs neutrons e.g. cadmium to slow the rate of the reactions. A moderator increases the probability that an atom of U235 will absorb a neutron so that it has the chance of undergoing fission.

[mworld]

2 billion years ago, when I was born, I documented what I saw and put it into a time casual so future scientists knew what it was like. That's why they can now talk with such confidence about the past.

[pycysyu]

1:50 We slow down neutrons not because fast neutrons cause uncontrollable reaction but because if we dont slow them down there would be no chain reaction. Yes fast reactors is a thing but they talked about thermal reactors in this video.

[thrunsguinneabottle]

Nope. The problem is that we use water as the coolant.
We need to keep that under enormous pressure to do its job.
Fortunately there is a MUCH BETTER technology - molten salt, which, at last, is getting the recognition it deserves. There are many proposed designs, which usually start with Thorium, and they turn the Thorium into fissile Uranium.
This is the way to go.

[Crimsonedge]

Moderators don't slow down neutrons to prevent an uncontrolled chain reaction. The control rods due that by absorbing them. The moderator material slows down the neutrons so as to increase their cross-section and thus increase the likelihood that a neutron will hit a neighbouring atom and cause a fission without just bouncing off. One must keep in mind that 95% of an atom is actually empty space.

[cuestamx]

There are Nuclear reactors that work with natural uranium. So no need to enrich. Canada has many of those alongside India, China and Argentina.
Also the moderator slows down the neutrons so that the chain reaction occurs. You see U235 will “react” with thermal neutron (aka low energy neutrons) but the neutrons born from fission are fast neutrons (aka high energy neutrons) and U235 will not produce fision with most of them.
What the moderator does is slow down the neutrons, it makes them lose energy.
What controls the reaction in Nuclear power plants is the control rods and also boron.
If you “lose” the moderator there won’t be an explosion, the reaction would stop. The problem is most moderators are also coolants. So the reaction stops but you still need to cool the core because of decay heat

[gravijta]

Gone fission for tuna, the chicken of the sea