4 ms·

Do you burn it? Why is it than that every reactor I know of, in US, WE, Japan, stores tones of extremely dangerous waste on site?

ansible 11y ago
I think brrt is talking about "burning" nuclear waste in a molten-salt reactor or similar. Some types of existing fission reactors can only utilize a small percentage of the uranium in their fuel rods, after which the rods must be removed. The rods must then be stored, and possibly reprocessed afterwards. MSR and other fission reactor types can utilize 100% of the fissionable material put into them, so this sort of leftover "waste" is not such a problem.
- anon1mous 11y ago
  Yeah, so there is a solution to nuclear waste - in fantasy land.
  - ars 11y ago
    It's called a breeder reactor, they are quite common in some places (but not in the US). I guess those places are "fantasy land"? Pretty cool since I can visit them.
PolLambert 11y ago
Since regulations don't allow any other option e.g. the US doesn't allow reprocessing. Also: what better place to temporarily store nuclear waste in the exact same place where it is produced where safety and security measures are already in place?
- anon1mous 11y ago
  Yeah, right next to a reactor, so that a meltdown causes 10x more damage.
- mentando 11y ago
  I will try without the condescending tone of the other commentor: Why does this not increase the possible damage a meltdown would cause? Or does it increase the possible damage, but the security is high enough that the expected damage is lower than storing it elsewhere?
  - pdkl95 11y ago
    First, a containment structure[1] is a key feature in any reactor[2]. These are massively over-engineered specifically to contain even unlikely problems. We learned that this was important after the SL-1 accident[3]. As you suggest, this is a feature designed to fail safely - the containment should keep the rest of us outside the building safe, and doesn't say anything about what happens to the stuff in side. > meltdown This term is thrown around a lot, and while solid fuel melting in a traditional reactor is a serious event, a lot of people seem to think that "meltdown" is some kind of terrible or damaging event. The reason people in the nuclear industry panic over a possible meltdown has little to do with safety; up until that point you could - in theory - still reasonably believe that the reactor could be fixed and (eventually) restarted. After a meltdown, you have to assume the core is trashed and is now a financial liability instead of your main source of revenue. Meltdowns are a terrible event financially. The actual melting of the fuel involves the passive-safety, which are usually designed to drain that fuel into (multiple) areas where it can cool down without criticality risk. All of this is still discussing very old features. This is like worrying about today's computers because vacuum tubes are fragile and need to be replaced when they burn out. Modern reactor design is very different, because we learned form the problems that happened in the original designs, just like any other technology. Unfortunately, propaganda based on radiophobia has been a serious roadblock. Ironically, this means we're stuck using older designs that should have been replaced decades ago with modern reactors that emphasis passive safety. If you're interested in a brief overview of these problems (and why some of us believe thorium breeder reactors are the answer for many of these problems), I recommend watching "Th"[4]. Just remember it's an overview, and they skip over some of the details to keep it short. [1] https://en.wikipedia.org/wiki/Containment_building https://en.wikipedia.org/wiki/Containment_building [2] a feature that was missing at Chernobyl, which is one of many reasons that accident affected such a large area [3] https://www.youtube.com/watch?v=qOt7xDKxmCM https://www.youtube.com/watch?v=qOt7xDKxmCM [4] http://thoriumremix.com/th/ http://thoriumremix.com/th/
Spooky23 11y ago
Because "just burning it" requires engineering and implementing a different nuclear technology with its own issues. Nuke advocates always practice magical thinking. Wave away safety concerns. Write off intractable waste disposal issues as "just bury it". The reality is that nuclear as it stands today is a relic of the Cold War. Solar, wind and gas are the future.
yk 11y ago
Because burning it involves superheated, radioactive phosphoric acid.
- ars 11y ago
  What are you talking about? No it doesn't.
  - yk 11y ago
    The designs I have seen dissolve the spent nuclear fuel in phosphoric acid and then operate with liquid fuel. ( Perhaps there are proposals that do not operate like that, but I think you want to homogenize the fuel as much as possible which means some kind of liquid fuel.)
    - ars 11y ago
      How do you superheat phosphoric acid? Wouldn't it dissociate? It's not used for an active reactor, but rather to dissolve cold fuel and extract more usable uranium. Liquid fuel reactors don't use phosphoric acid, they use uranium tetrafluoride (a salt) or water.
      - yk 11y ago
        No, you want to burn all the short lived isotopes, not just Uranium. So the designs I am talking about use spend fuel dissolved in acid as a fuel. There is also spent fuel recycling, where you take Uranium and Plutonium out of spent fuel and manufacture MOX fuel, but that is an entirely different process.

ansible 11y ago

I think brrt is talking about "burning" nuclear waste in a molten-salt reactor or similar. Some types of existing fission reactors can only utilize a small percentage of the uranium in their fuel rods, after which the rods must be removed. The rods must then be stored, and possibly reprocessed afterwards. MSR and other fission reactor types can utilize 100% of the fissionable material put into them, so this sort of leftover "waste" is not such a problem.

anon1mous 11y ago
Yeah, so there is a solution to nuclear waste - in fantasy land.
- ars 11y ago
  It's called a breeder reactor, they are quite common in some places (but not in the US). I guess those places are "fantasy land"? Pretty cool since I can visit them.

PolLambert 11y ago

Since regulations don't allow any other option e.g. the US doesn't allow reprocessing. Also: what better place to temporarily store nuclear waste in the exact same place where it is produced where safety and security measures are already in place?

anon1mous 11y ago
Yeah, right next to a reactor, so that a meltdown causes 10x more damage.
mentando 11y ago
I will try without the condescending tone of the other commentor: Why does this not increase the possible damage a meltdown would cause? Or does it increase the possible damage, but the security is high enough that the expected damage is lower than storing it elsewhere?
- pdkl95 11y ago
  First, a containment structure[1] is a key feature in any reactor[2]. These are massively over-engineered specifically to contain even unlikely problems. We learned that this was important after the SL-1 accident[3]. As you suggest, this is a feature designed to fail safely - the containment should keep the rest of us outside the building safe, and doesn't say anything about what happens to the stuff in side. > meltdown This term is thrown around a lot, and while solid fuel melting in a traditional reactor is a serious event, a lot of people seem to think that "meltdown" is some kind of terrible or damaging event. The reason people in the nuclear industry panic over a possible meltdown has little to do with safety; up until that point you could - in theory - still reasonably believe that the reactor could be fixed and (eventually) restarted. After a meltdown, you have to assume the core is trashed and is now a financial liability instead of your main source of revenue. Meltdowns are a terrible event financially. The actual melting of the fuel involves the passive-safety, which are usually designed to drain that fuel into (multiple) areas where it can cool down without criticality risk. All of this is still discussing very old features. This is like worrying about today's computers because vacuum tubes are fragile and need to be replaced when they burn out. Modern reactor design is very different, because we learned form the problems that happened in the original designs, just like any other technology. Unfortunately, propaganda based on radiophobia has been a serious roadblock. Ironically, this means we're stuck using older designs that should have been replaced decades ago with modern reactors that emphasis passive safety. If you're interested in a brief overview of these problems (and why some of us believe thorium breeder reactors are the answer for many of these problems), I recommend watching "Th"[4]. Just remember it's an overview, and they skip over some of the details to keep it short. [1] https://en.wikipedia.org/wiki/Containment_building https://en.wikipedia.org/wiki/Containment_building [2] a feature that was missing at Chernobyl, which is one of many reasons that accident affected such a large area [3] https://www.youtube.com/watch?v=qOt7xDKxmCM https://www.youtube.com/watch?v=qOt7xDKxmCM [4] http://thoriumremix.com/th/ http://thoriumremix.com/th/

Spooky23 11y ago

Because "just burning it" requires engineering and implementing a different nuclear technology with its own issues. Nuke advocates always practice magical thinking. Wave away safety concerns. Write off intractable waste disposal issues as "just bury it". The reality is that nuclear as it stands today is a relic of the Cold War. Solar, wind and gas are the future.

yk 11y ago

Because burning it involves superheated, radioactive phosphoric acid.

ars 11y ago
What are you talking about? No it doesn't.
- yk 11y ago
  The designs I have seen dissolve the spent nuclear fuel in phosphoric acid and then operate with liquid fuel. ( Perhaps there are proposals that do not operate like that, but I think you want to homogenize the fuel as much as possible which means some kind of liquid fuel.)
  - ars 11y ago
    How do you superheat phosphoric acid? Wouldn't it dissociate? It's not used for an active reactor, but rather to dissolve cold fuel and extract more usable uranium. Liquid fuel reactors don't use phosphoric acid, they use uranium tetrafluoride (a salt) or water.
    - yk 11y ago
      No, you want to burn all the short lived isotopes, not just Uranium. So the designs I am talking about use spend fuel dissolved in acid as a fuel. There is also spent fuel recycling, where you take Uranium and Plutonium out of spent fuel and manufacture MOX fuel, but that is an entirely different process.