Nuclear Waste Question

[Mrdeals]

There seems to always be some debate about how/where to properly store spent uranium. Which to my understanding remain radioactive for thousands of years after. After which time the uranium would turn into a stable element (correct?)

My question is:

Would there be anyway to speed up the half life of radioactive material? Turning it into a stable element and releasing it back into the world?

[Trinopus]

There isn’t any way to change the half-life of an element… But by bombarding an element with neutrons, in a breeder reactor, the element can be “cooked” – forced to transmutate at a higher rate. This is how some radioactive elements, like weapons Plutonium, is created, but the process can also be used to destroy dangerously radioactive elements.

Research is ongoing in using breeder reactors to denature dangerous waste. The process isn’t fully developed at this point.

[watchwolf49]

@Mrdeals

[snip] … Turning it into a stable element and releasing it back into the world?

I’m pretty sure that stable element the waste turns into is lead, it will need to stay buried forever.

[Hari_Seldon]

There is a different kind of reactor, called a traveling wave reactor: Traveling wave reactor - Wikipedia

A traveling-wave reactor (TWR) is a type of nuclear fission reactor that can convert fertile material into usable fuel through nuclear transmutation, in tandem with the burnup of fissile material. TWRs differ from other kinds of fast-neutron and breeder reactors in their ability to use fuel efficiently without uranium enrichment or reprocessing, instead directly using depleted uranium, natural uranium, thorium, spent fuel removed from light water reactors, or some combination of these materials.

The name refers to the fact that fission remains confined to a boundary zone in the reactor core that slowly advances over time. TWRs could theoretically run, self-sustained,
for decades without refueling or removing spent fuel.

It “burns” over 90% of its nuclear fuel, leaving mostly short-lived waste (half life under 100 years) and much less of it. The method is proven, but that is not the end of the development cost. Reactors have to be built, certified, there is a learning curve and all the development of the past 70 years have to be scrapped. Only governments could finance it and none that I know of has (although there was some suggestion that China is exploring it). Maybe if all the money spent on the elusive fusion reactor had gone to travelling waves instead, but I am dreaming.

[Stranger_On_A_Train]

The traveling wave reactor is far from proven. In fact, one has never been built or operated on any scale, and there is significant contention for how difficult it would be to implement and control a TWR. However, there are a number of reactor designs that can consume the bulk of the actinides and fission products produced by fission of [SUP]235[/SU]U leaving only short-lived isotopes that can be stored until they decay. Such ‘burner’ reactors produce more energy than a once-through [SUP]235[/SU]U and do not require the reprocessing effort and risks of breeder reactors, though they still typically require some degree of separation to gain efficient use of the primary fuel. The Integral Fast Reactor, Liquid Metal Cooled Fast Reactor, Molten Salt Reactor, Liquid Fluoride Thorium Reactor, and Subcritical Fission-Fusion Reactors all have a substantial proof of concept, with several having been operated at useful power production levels and tested in various regimes for stability, and all provide a substantial degree of burnup and efficient use of nuclear fuel; many can also use [SUP]232[/SUP]Th as a fuel, as well as different formulations of mixed oxide (MOX) without having to physically reconfigure the reactor.

Stranger