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Do fuel handlers work for the plants ? Or is their a specific task force so to speak that travels from plant to plant carrying out and handling ?

@@TheHeatExchang3 Both. GE brought in their team of drivers who were ususally "vessel techs" also. And there were 6-8 of us from plant staff who moved fuel and operated the fuel transfer system.

​@@dannywilliamson3340getting my fuel moving cert soon. Maybe I'll be on the bridge with you one day

By "containers" you mean fuel assemblies? If so, the storage racks have neutron absorbing material built into them, and, in the core, all control rods are inserted during fuel handling. So the reactor is in cold shutdown.

Those are hollow shells designed to support control rod and fuel bundles in each cell, called a blade guide

They swing around while moving through the water because they're hollow tubes.....relatively light.

This is the core of the reactor and the spent fuel pool 👍 the camera is mounted to the mast of the refueling machine, 60 or more feet underwater

Ccherenkov radiation shows up when photons are traveling faster than speed of light

It's caused by charged particles (electrons in this case) moving faster than light (light moves slower in water so this is possible)

There is no such thing as stopped reactor. Until it's decommissioned, it's always active. For example, Chernobyl reactors stopped producing electricity in 1999 (13 years after the infamous event), are still in decommissioning phase, and there is still staff on-site. Visible Cherenkov radiation is due to radiation from reaction products, not fission.

The reactor is in cold shutdown while this is done.

Moderator and coolant. Which means if you lose your coolant, you also lose your moderator and thus the loss of water also means loss of radioactivity. Chernobyl taught us why using Graphite for a moderator and water for a coolant was a bad bad idea.

That wouldn't cause a problem.

Chicken Little checks in.

Are you talking about the removable top of the vessel, were the control rods mechanism is siting? If you do, than, at least from what I know, during operation the reactor cavity (the pool the reactor is at the bottom of..) is dry, so the head of the reactor is also dry, but maybe there are some places that do keep the pool full of water, since water serves as a radiation shield. But that's only for PWR. BWR are always, from what I know, completely submerged, the pool is full with water, and that's probably because on the head of an BWR there is no control rods mechanism, do to the fact that control rods are inserted from under the reactor, so the mechanism is under the reactor. It's quite a shame that PWR pools aren't full during operation, since it's so cool and nice to see the heug equipment and the huge reactor at the bottom of the enormous pool. Every thing is super cool when under deep water, especially when it's something technological and big, like nuclear reactors and submarines.. The water gives it an sort of spooky but yet sublime feeling....

@@neilzukov2921 Yes, that's exactly what im asking, does this mean that the refueling process has a process where the water surface rises and then falls again?a professional answer. Thank you very much

Rods are replaced on schedule, a third of them at a time. Burnout rates can be calculated if you know where did that rod was and for how long, to some good precision even on a piece of paper. Replacements are done way before full burnout due to effects of fission products on reactivity. This is a common treat of current generation of reactors. Fresh rods are never stored at critical mass. They're put in a separate pool prior to insertion, and similarly moved by crane.

hold up..

Did you use the wrong thermometer again?

Very good. From the operator's cab, it's about 70 feet down to the top of the core.

Yeah, it is available. I just bought it but I don't know why the cops are yelling outside my house

Afterglow, its still emmitting after its been in use. The cherenkov radiation dims down when the fuel stops fission. But even after fission has stopped it will still radiate for a while

@@TGLasers so in these used rods there is some fuel?

@@oskarmiazga1951 This is the radioactive fuel. the rods themselves are the fuel

@@TGLasers i know but aren,t they completly empty after use

@@oskarmiazga1951 No. They are "used up" but theres still alot of fuel left in them. there just inst enough for the power plants to efficiently produce power with them so they are decommisioned before all is fissioned up

That's the operator shaking it to make sure it seats fully.

None. It's visible light.

@@paulanderson79 Actually there's a lot of UV light in it

Dummy fuel bundles are used to hold the control blades in position.

The single one is the real fuel assembly. The double one is just a place holder to keep everything properly aligned while moving the fuel in and out.

Cherenkov radiation. Particles moving faster than light through water.

@@mczenk5095 more accurately entering the water where their speed is low than it would be in a vacuum. (Light travels more slowly in water).

Not even that much. There's several meters of water between you and the core.

Exactly.

Yes, it is very hot but not so hot that it instantly boils water. In fact, that spent fuel pool is cool enough for divers to swim in.

@@ShimrraJamaane do spent fuel is where the DU came from?

@@aspopulvera9130 The majority of DU munitions is sourced from the byproduct of uranium enrichment which contains a low percentage of fissile uranium. Some DU is extracted from spent fuel but that is a significantly smaller amount (almost negligible). Here is a WHO fact sheet on DU: web.archive.org/web/20120815092349/www.who.int/mediacentre/factsheets/fs257/en/

@@aspopulvera9130 No, DU comes from enrichment. It's "depleted" of U235, which goes into reactor.

Coniver Divide why does the rest go to waste? Why aren’t they using the full true capacity?

@@Inorbit97 the uranium used in fission reactions is uranium-235, the uranium which is found abundantly in nature is uranium-238, with a tiny proportion of uranium-235 mixed in with it. This uranium 238 is further enriched industrially so that the quantity of uranium 235 in the rods increases. After the enrichment, around 98% of the rod is uranium 238, and 2% Uranium-235. A fuel rod typically has a lifespan of 3 years, over these years the uranium 235 gets used up, and the waste products that are formed make up 5% of the composition of the rod, the rest is all uranium-238, which could be recycled by nuclear reprocessing, but doing so is considered too expensive by the companies which provide the power, thus, the rods are thrown away as nuclear waste and keep decaying and giving off all the remaining energy over thousands of years.

Breeder reactors are not to generate power, but to create fuel. The rrods in these reactors get re-proressed to separate all the isotopes and reuse some for fuel. India, which doesn't have a lot of Uranium, bu a lot of Thorium is using Thorium breeder reactors to make Uranium for their thermal reactors. But the rest certainly does not go to waste. Even the U238 ( reactor fuel is only about 3% U235) can be turned into Plutonium or used for anti-tank bullets.

Yes, and thorium fuel cycle. Why do we waste our time with uranium, when there's abundant thorium that you don't even have to enrich? The answer to both questions is plutonium production, precisely.

0. Several feet of water stops all the ionising radiation.

CAN YOU SHUT UP?

You would have lost $0.00 by not posting this

probably for accessibility reasons, the radiation resistant camera is too big to be used under the pressure vessel, if you notice every video of it the camera goes through a tube

Core neutronics simulations will be able to predict burnup of fuel rods. Buildup of fission products give radiation signatures that are also a reflection of burnup. Most PWRs operate in ‘batches,’ where one third of the fuel is removed and replaced. The rest of the fuel rods are moved around to make burnup more uniform over time.

@@ArchangelUltra Cool, Thanks.

They get moved around from the outside to the center then out. The rods are far from truly spent, but are pulled for safety reasons mostly because they can crack open or have unstable reactivity as the isotope composition changes internally.