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It seems that thorium reactors produce less nuclear waste than uranium reactors: https://en.wikipedia.org/wiki/Thorium_fuel_cycle#Fission_product_wastes https:/

It seems that thorium reactors produce less nuclear waste than uranium reactors: https://en.wikipedia.org/wiki/Thorium_fuel_cycle#Fission_product_wastes https://en.wikipedia.org/wiki/Thorium_fuel_cycle#Fission_pro.... Could someone with more knowledge on the subject give a rough estimate of the amount of waste we would be talking about?

badloginagain 12y ago
Uranium reactors use something like 2% of the total energy available in the uranium. Molten-salt-reactors use something like 98% of the available energy. Additionally, the 2% that is waste contain extremely rare derivatives that can be used as cancer "smartbombs", metals pivotal to deep space NASA missions, etc. This has a pretty good overview: https://www.youtube.com/watch?v=P9M__yYbsZ4 https://www.youtube.com/watch?v=P9M__yYbsZ4
- fordiman 12y ago
  A MSR breeder can potentially burn 98% of the available energy; ThorCon is a converter, but not a breeder. From what I can glean from their website and documentation, it looks like they get about 20% burnup.
LarsJorgensen 12y ago
There are many different thorium designs based on different objectives. The original designs assumed that we would run out of uranium so the primary objective was breeding. It is clear now that we have much more uranium than they thought. We should start with an understanding of how much waste is there currently from today's reactors. Roughly one coke can would hold all the waste generated from one person's electricity (European standards roughly 1kW) for a lifetime. We can reduce the volume of waste readily by removing the uranium and re-enriching it. This can be done with virtually all reactors including todays reactors. This will remove 90% of the waste volume but does nothing to reduce the hazards of the waste. We can remove the elements that are heavier than uranium (transuranics or TRUs). This is the long term hazard. This material can be recycled into a reactor to be fissioned (destroyed forever not simply buried). This can be done to a very limited extent in some of today's reactors. But either IFR or molten salt reactors would really be the appropriate way to eliminate the long term hazards of nuclear waste. Such a process will be limited by our ability to separate the TRUs from the fission products. We expect to achieve around 99% separation so to reduce the long term hazard 100 fold. The near term hazard comes from the fission products. These will decay in a reasonable time. Every 30 years the radioactivity will decay by half. So by 300 years you are back to roughly background radiation. 300 years is short enough we know how to build containers to last that long.

badloginagain 12y ago

Uranium reactors use something like 2% of the total energy available in the uranium. Molten-salt-reactors use something like 98% of the available energy. Additionally, the 2% that is waste contain extremely rare derivatives that can be used as cancer "smartbombs", metals pivotal to deep space NASA missions, etc. This has a pretty good overview: https://www.youtube.com/watch?v=P9M__yYbsZ4 https://www.youtube.com/watch?v=P9M__yYbsZ4

fordiman 12y ago
A MSR breeder can potentially burn 98% of the available energy; ThorCon is a converter, but not a breeder. From what I can glean from their website and documentation, it looks like they get about 20% burnup.

LarsJorgensen 12y ago

There are many different thorium designs based on different objectives. The original designs assumed that we would run out of uranium so the primary objective was breeding. It is clear now that we have much more uranium than they thought. We should start with an understanding of how much waste is there currently from today's reactors. Roughly one coke can would hold all the waste generated from one person's electricity (European standards roughly 1kW) for a lifetime. We can reduce the volume of waste readily by removing the uranium and re-enriching it. This can be done with virtually all reactors including todays reactors. This will remove 90% of the waste volume but does nothing to reduce the hazards of the waste. We can remove the elements that are heavier than uranium (transuranics or TRUs). This is the long term hazard. This material can be recycled into a reactor to be fissioned (destroyed forever not simply buried). This can be done to a very limited extent in some of today's reactors. But either IFR or molten salt reactors would really be the appropriate way to eliminate the long term hazards of nuclear waste. Such a process will be limited by our ability to separate the TRUs from the fission products. We expect to achieve around 99% separation so to reduce the long term hazard 100 fold. The near term hazard comes from the fission products. These will decay in a reasonable time. Every 30 years the radioactivity will decay by half. So by 300 years you are back to roughly background radiation. 300 years is short enough we know how to build containers to last that long.