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Nuclear waste

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Khandro | 18:17 Wed 08th Sep 2010 | Science
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With space travel becoming more and more commonplace, might it be possible to fire waste nuclear material at the sun, which is radioactive (I believe) anyway?
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Feasible but what if there was an accident like the Space Shuttle Challenger?
A lot of radioactive waste is so called low level waste, this is material that has become contaminated incidentally during the processing and handling of nuclear materials. It is nowhere near as radioactive as uranium fuel but is too dangerous to be released directly into the environment. It is very bulky and would need to be concentrated considerably to get it into a rocket. Easier and safer to encase it in concrete and bury it in a very stable rock formation.
Another problem is that a considerable amount of energy would be needed to send it into the sun. It would be easier to send it to jupiter.
Something like this would only ever become viable once space travel hits the masses, you and i.

Space elevator, something like that.

To the poster above me, i don't understand how less energy would be spent sending said objects to Jupiter? Considering at present the most costly part of any launch is escaping earths gravity.
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I take the point that there would, even if rockets became super-safe and cheaper, some ellement of risk, but the stuff has to be moved around on earth anyway, and so there will always be risk involved. Air transport, once risky, is nowadays the safest form of travel.
It costs about 32 million euros per tonne to launch the Galileio satelites and they do not break Earth orbit.

A 1 GW reactor produces about 1/2 tonnes of high level radioactive waste per year

Reprocessing at Sellafield costs £800K per tonne approximately

Not only that but THORP at sellafield should be able to process 900 tonnes a year and their books are filled for 15 years

Arienne 5 can get about 6.5 tonnes to GeoStationary orbit

At that rate you'd need to be launching one every other day.

Costs would not be likely to fall with demand because much of the cost is fuel.

So regardless of the safety argument it doesn't make financial sense either.
If you read this paragraph "Isn’t the waste from nuclear reactors a huge problem?" about nuclear waste from the book "Sustainable Energy without the hot air" by Professor John MacKay of Cambridge university, which starts on page 169 of the book and continues onto page 170, you will see that the amount of nuclear waste is extremely small:

http://www.inference....ir/c24/page_169.shtml
In fact it is:
25ml per year per person
when municipal waste is 517kg per year per person and
hazardous waste 83kg per person

A lifetime's worth of nuclear waste is less than 2 litres. Multiply by 60 million (UK) and it could all be stored in one tenth of a square kilometre 1 metre deep.

As MacKay says:

"There are already plenty of places that are off-limits to humans. I may
not trespass in your garden. Nor should you in mine. We are neither of us
welcome in Balmoral. “Keep out” signs are everywhere. Downing Street,
Heathrow airport, military facilities, disused mines – they’re all off limits.
Is it impossible to imagine making another one-square-kilometre spot –
perhaps deep underground – off limits for 1000 years?"
Yes I think he is talking about high level nuclear waste.

Surprisingly the problem with this is nowadays the use for it. There is I think currently over 100 tonnes of Plutonium sitting up at Sellafield with nothing to do.

The fast breeder reactor program (which would use it) failed and there is far too much for nuclear weapons

And it obviously has to be stored securely

There is a scheme for MOX which is Mixed OXide fuel which reactors could use which would be a mixture of this and other fuels but at the moment it's proving difficult.

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

There is obviously a security issue around MOX fuel - An Iranian MOX reactor would be a worry

As mentioned below Low level waste isn't really hazardous and can be just things like overalls that have been in a designated area. It is 90% of the volume but only 1 % of the radioactivty

Medium level waste is a bigger issue it has 7% of the volume and 4% of the radioactivity

High level has 3% of the volume and 95% of the radioactivity

Medium to Long term though Nuclear Fusion is the answer as you can intelligently choose your materials to have much shorter half lifes. People do tend to dismiss it as a pipe dream but generally they haven't been following it's steady methodical progress and only remember the overly ambitious promises of the 50s
Hi Tonester, hope the following helps
The sun being a massive object relative to the earth has a much deeper and steeper ‘gravity well‘, than the earth. The earth is positioned near the top of the well and has a relatively small gravity ’well’ of its own. I cannot remember the exact figures but I think the amount of energy needed to get from the sun to the earth is about 20 X the energy needed to get from the earth to Jupiter once the earth’s gravitational field has been escaped . To get something to fall directly into the sun you would have to cancel out its orbital velocity, which in this case is the same as the earth’s, about 70,000 miles per hour having already imparted the energy necessary to leave earth.
It is something I've considered int he past, but I figured the risk if something went wrong and blew radioactive debris over the whole area doesn't make it an ideal plan, even if the finances could be sorted.

I'm expecting future research to learn how to convert it into something safe eventually anyway. We've come a long way knowledgewise in a few hundred years, I can't see it taking millions of years to come up with a more earthbound solution.
Sellafield used to be called Windscale until the accident. The name was changed to help us forget about the accident. Authorities predictably dismiss the consequences of the release of radioactive material.

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

Humans cannot be trusted with his technology and the byproducts that remain dangerous for thousands of years.

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