How viable is reusing nuclear waste?

[blackhole123]

I would love to see a paper by a scientist that dealt specifically with the energy involved in reusing nuclear waste. I mean, it seems like the characteristics of nuclear reactions would demand you use as much energy as was given off to get back to what you started with. I'm sure scientists have figured out ways around this, but I am just wondering to what extent that is true.

 

If we had to pump 75% of the energy we got from nuclear power plants into reusing the waste it wouldn't look so good. But again, I have never seen any actual numbers on this.

[Moontanman]

Recycling nuclear waste will make what we call waste valuable fuel.

 

http://www.world-nuclear.org/info/inf04.html

 

Recycling used fuel

 

Any used fuel will still contain some of the original U-235 as well as various plutonium isotopes which have been formed inside the reactor core, and the U-238c. In total these account for some 96% of the original uranium and over half of the original energy content (ignoring U-238). Reprocessing, undertaken in Europe and Russia, separates this uranium and plutonium from the wastes so that they can be recycled for re-use in a nuclear reactor (see page on Processing of Used Nuclear Fuel). Plutonium arising from reprocessing is recycled through a MOX fuel fabrication plant where it is mixed with depleted uranium oxide to make fresh fuel (see page on Mixed Oxide Fuel). European reactors currently use over 5 tonnes of plutonium a year in fresh MOX fuel.

 

Major commercial reprocessing plants operate in France, UK, and Russia with a capacity of some 5000 tonnes per year and cumulative civilian experience of 80,000 tonnes over 50 years. A new reprocessing plant with an 800 t/yr capacity at Rokkasho in Japan is undergoing commissioning. France and UK also undertake reprocessing for utilities in other countries, notably Japan, which has made over 140 shipments of used fuel to Europe since 1979. Until now most Japanese used fuel has been reprocessed in Europe, with the vitrified waste and the recovered uranium and plutonium (as MOX fuel) being returned to Japan to be used in fresh fuel (see page on Japanese Waste and MOX Shipments From Europe). Russia also reprocesses some spent fuel from Soviet-designed reactors in other countries.

 

There are several proposed developments of reprocessing technologies (described in the page on Processing of Used Nuclear Fuel). One technology under development would separate plutonium along with the minor actinides as one product. This however cannot be simply put into MOX fuel and recycled in conventional reactors; it requires fast neutron reactors which are as yet few and far between. On the other hand, it would make disposal of high-level wastes easier.

 

 

These reactors would be able to use reprocessed waste or actually use fuel completely up.

 

http://en.wikipedia.org/wiki/Fast_breeder_reactor

 

http://en.wikipedia.org/wiki/Generation_IV_reactor

 

Then there are Thorium reactors.

 

http://en.wikipedia.org/wiki/Thorium

[Charlatan]

I would love to see a paper by a scientist that dealt specifically with the energy involved in reusing nuclear waste. I mean, it seems like the characteristics of nuclear reactions would demand you use as much energy as was given off to get back to what you started with. I'm sure scientists have figured out ways around this, but I am just wondering to what extent that is true.

 

If we had to pump 75% of the energy we got from nuclear power plants into reusing the waste it wouldn't look so good. But again, I have never seen any actual numbers on this.

 

Well, if they use up all the wood in a camp fire they will not be able to burn it again will they? If you were to reuse nuclear waste, wait... what makes it nucleur waste? If you could use it again it wouldn't be waste, yes?

[swansont]

Well, if they use up all the wood in a camp fire they will not be able to burn it again will they? If you were to reuse nuclear waste, wait... what makes it nucleur waste? If you could use it again it wouldn't be waste, yes?

 

It's waste because it contains fission products and won't sustain a chain reaction. Not all of the U-235 has been used up, as Moontanman's quote clearly states.

[Moontanman]

Another point that needs to be made is that the U-238 that is left over in waste can be used in breeder reactors to make fissile material as well.