Eli5 why can’t radioactive waste be used again? Why is it waste?
In: 288
The part that is being reused is not called waste.
By quantity, most of it is conventional waste that had some contact with radioactive material and has tiny traces stuck on it. Handle some radioactive material with gloves and traces of it will stick to the gloves. They are now radioactive waste. The container it was in is probably radioactive waste, too. Generally the activity here is very low (few decays per second), so it’s no problem to store these materials safely.
If we look at spent fuel from nuclear reactors: The reactors don’t run on radioactive decays. They use a chain reaction where neutrons hit an uranium nucleus and split it, a process which releases more neutrons that can then split more uranium nuclei and so on. There is a bit of radioactivity as well but that’s just an unwanted side effect. We would love to use non-radioactive elements in nuclear reactors, but it turns out that there are none that could do this chain reaction.
Spent fuel has largely three components:
* some of the original uranium. That is obviously useful, it’s like unburnt fuel in a fire. In Europe this is commonly extracted and reused. The US doesn’t do this for political reasons.
* The elements produced from splitting the uranium – some are radioactive, some are not. There is no practical use for them – it’s like the ash of a fire, you can’t burn that (and unlike actual ash, you definitely don’t want to use this as plant fertilizer!).
* A bit of other stuff that is produced as side effect in a reactor, mostly from neutrons hitting uranium without splitting it (generally radioactive). This can be used as fuel in specialized reactors.
Latest Answers