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Recycle Radioactive Material?

  1. Sep 15, 2004 #1
    Is there any way to recycle nuclear waste or to stop its radioactivity/emissions besides burying it like a dog?

    Re: My Hometown
     
  2. jcsd
  3. Sep 16, 2004 #2

    selfAdjoint

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    The Integral Fast Reactor (IFR) design can consume high rad waste and put out low rad waste. The low rad waste is not only less radioactive, but its half life is only decades instead of thousands of years.
     
  4. Sep 16, 2004 #3
    Spent nuclear fuel is refined and reprocessed in European countries, but it is not done in the United States (reenrichment of uranium is generally left to the military and may cause concerns over bomb production). Since spent nuclear fuel is still roughly 95% Uranium-238, the waste shouldnt need to be stored down in the ground forever.

    http://web.em.doe.gov/tie/yucca1.html
     
  5. Sep 17, 2004 #4

    mee

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    I have heard that the temperature in Yucca Mountain, when full of waste, will be quite high. What is the reason we can't use this waste to fuel steam turbines for a long time?
     
  6. Sep 17, 2004 #5
    Recycled Resources...


    My understanding is that all nuclear waste is recyclable, such examples are nuclear batteries, reprocessed spent fuel rods, etc.

    However, I believe the United States motivation is based upon the laws of economics. It is cheaper to re-mine Uranium than to reprocess spent fuel rods. If someday it becomes cheaper to reprocess spent fuel rods than re-mine Uraniun, the prospects of recycling the United States spent nuclear stockpile may become more economically appealing.

    Perhaps its just a matter of advancing nuclear recycling technology to make such prospects more economically feasable.

    I would personally like to see spent nuclear fuel waste reprocessed into giant nuclear batteries for some large industrial nuclear battery power plants. If only federalistic scientists were as objective as I am...

     
    Last edited: Sep 17, 2004
  7. Sep 18, 2004 #6
    Why spent fuel decay heat cannot be used to produce electricity

    Carnot's law. The hotter the core temperature of a heat engine, absolutely relative to the coolant temperature, the more efficient it is. A heat engine (such as a turbine, which would be a poor choice for a low-temperature heat source) running off of the decay heat of spent reactor fuel would be too inefficient to produce electricity economically.

    However, some industrial processes demand low enough temperature that their heat can be economically supplied by the decay heat of spent fuel rods. China recently announced plans to use spent nuclear reactor fuel to provide process heat for desalination plants. Though it might conceivably be feasible to use just the decay heat, China actually plans to re-use the spent fuel rods in a low-heat reactor to provide the heat for the desalination processes. If you are wondering why China wouldn't just continue using the same rods in the power reactors, the answer is that in their spent conditions the rods cannot produce enough heat to run the far more expensive power reactors (and it help to understand here that power reactors (nuclear reactors hooked up to turbines and dynamos) are much more complicated and therefore expensive than reactors that simply heat water (such as university research reactors and reactors solely providing industrial process heat).

    Because of the massive investment that is tied up in a power reactor, it has to be run at nearly maximum power nearly all of the time in order to produce a positive return on that investment. That is one reason why fuel rods that still have plenty of burnable fuel in them are removed from power reactors after only ~4 years of service.
     
    Last edited: Sep 18, 2004
  8. Sep 18, 2004 #7

    mee

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    Anyone know if the mining of uranium is now safer than it was in the past when all of the native americans became ill from working in them?
     
  9. Sep 21, 2004 #8
    Why don't we reprocces nuclear fuel

    It is to my understanding that according to the Strategic Arms Limitation Talks (SALT) that the US is not allowed to recycle the fuel, as it is considered stockpiling nuclear arms.

    I may be wrong about this but got my information from a recruiter that works for navy.

    Can anyone confirm this?
     
  10. Sep 21, 2004 #9
    Jimmy Carter's 1977 reprocessing ban

    Implicitly according to Richard Garwin, the reprocessing ban does not have anything to do with the SALT treaties.


    • The Weapons Connection

      Following the lead of his predecessor, Gerald Ford, President Jimmy Carter in 1977 issued a directive forbidding reprocessing of civilian power reactor fuel in the United States and attempting to lead other nations to the same goal, primarily to avoid the contribution that separated plutonium could make to proliferation of nuclear weapons. At the time, it was clear that direct disposal of spent fuel was less costly than reprocessing fuel and recycling the plutonium and uranium. Nevertheless, the costs of the two methods are still being disputed by their partisans. A 1994 study of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development claims no significant difference between the two options, but the study uses for direct disposal the very high cost per unit of spent fuel estimated for the small Swedish program, rather than those for the massive U.S. activity. Nevertheless, it estimates the reprocessing and recycling approach to be about o.o6 cent per kWh more costly than the direct disposal of spent fuel. This is a small fraction of the average price paid for electrical energy in the United States – some 6 cents per kWh – but that same report indicates that o.o1 cent per kWh is about $1 million per year per reactor. For the hundred or so reactors in the United States, o.o6 cent per kWh additional cost would total some $6oo million per year. Other estimates that involve the construction of new reprocessing facilities, such as the one being built at Rokkasho-Mura, Japan, result in much higher costs for reprocessing-some 0.5 cent per kWh....

      If the American companies producing electricity today had to convert to reprocessing and bear the capital cost of construction of the necessary industrial complexes, they would be spending about o.65 cent more per kWh than the o.1 cent per kWh they pay today, to get rid of the spent fuel, which disposal is to be managed, not by themselves, but by the Department of Energy.14 With an average cost of electricity of some 5.9 cents per kWh (e.g., in 1997 8.5 cents/kWh for residential customers, 7.6 for commercial, and 4.6 for industrial), this would increase the cost of electricity by about 9%, and it would not ease significantly the problem of disposal of nuclear waste.
    (Richard Garwin & Georges Charpak. Megawatts and Megatons: A Turning Point in the Nuclear Age. pp144-145.)



    Bernard Cohen also has detailed the 1977 Carter administration ban on reprocessing and he further also did not connect it with the SALT treaties. Bernard Cohen's most popular book on nuclear energy is published online here. In Chapter 13, he writes:


    • ...the Carter Administration saw fit to go a step further. It decided to try to prevent the acquisition of reprocessing technology by nonnuclear weapons nations. As you may recall, reprocessing is a bottleneck that must be passed if nuclear power plants are to be used to make bomb materials; thus the goal of the government was, in principle, a desirable one. However, the method for implementing it was disastrous.

      At that time (1977), Germany was completing a deal to set up a reprocessing plant in Brazil, Japan was building a plant, and France was negotiating the sale of plants to Pakistan and Korea. The Carter goal was to stop these activities through moral and political pressure. To set the moral tone for this effort — essentially to "show that our heart is in the right place" — he decided to defer indefinitely the reprocessing of commercial nuclear fuel in the United States.* This was the move that prevented the Barnwell plant from operating.

      There were several problems with this approach. One was that the U.S. Government continued to do reprocessing in its military applications program, which was something of a dilution of the high moral tone being advertised....

      But the worst problem with the Carter initiative was that it failed to achieve much in the way of results. The United States had enough political leverage over South Korea to force that country to cancel its purchase of a reprocessing plant. France cancelled its sale to Pakistan, probably in recognition of the fact that Pakistan had expressed ambitions for building nuclear weapons, but perhaps also partly as a result of American political pressure. However, the German deal with Brazil was not cancelled in spite of constant political pressure, including several face-to-face meetings between President Carter and German Chancellor Schmidt. The Japanese reprocessing plant was completed and started up. No other reprocessing activity anywhere in the world except in the United States was stopped by the Carter initiative.
     
  11. Sep 23, 2004 #10
    Honestly, shoot it into space... yes people say we cant just send out litter into space.... WHY NOT?
    BTW, yes i know its rather dangerous to send a rocket packed with nuclear waste into space. With all the rockets that blow up still! Its bound to send nuclear waste to the 4 corners of the world
     
  12. Sep 24, 2004 #11
    Can we launch it into the sun? Otherwise it should be launched slowly enough that it will decay in time before it contaminates some alien ecosystem. Imagine if one day high-speed alien bio trash smashed into Earth, and 1 ppm of whatever it is was enough to cataclysmically change the environment. Maybe life on Earth was caused by intergalactic alien garbage?
     
  13. Sep 25, 2004 #12

    Chronos

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    Yikes! :bugeye: Launching it period would be monumentally stupid. We can't even safely launch people into space. Can you imagine the consequences if the rocket exploded about 50 miles up in the atmosphere?
     
  14. Sep 25, 2004 #13

    Nereid

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    Or was inadvertently inserted into an orbit in which it came back to hit the Earth at >50 km/sec, or an orbit which the US early warning systems determined was a nuclear missile attack by a 'rogue nation', or ...
     
    Last edited: Sep 25, 2004
  15. Sep 25, 2004 #14
    Some caviats related to the idea of solar waste disposal

    According to the discussers of this on Know Nukes, heavy metals launched at the sun would be reduced to atoms (but not destroyed) near the surface and then blown outward with the other particles that make up the solar wind. Like some of those other solar wind particles, some of the nuclear waste would end up trapped in Earth's ionosphere.

    Another item of information gleaned from Know Nukes is that it takes more energy to launch things from the earth to the sun than it takes to launch things from the earth on a permanent trajectory out of the solar system.
     
  16. Sep 25, 2004 #15
    Those who said that if it blew up in our atmosphere, it'd suck, i already mentioned that
     
  17. Sep 26, 2004 #16

    Chronos

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    Agreed. I somehow missed your post.
     
  18. Oct 14, 2004 #17

    Morbius

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    I can "de-confirm" this.

    The SALT Treaty does NOT limit the ability of the USA to reprocess fuel.

    [ The Russians reprocess their fuel ].

    SALT counts missiles - it doesn't address the warhead fuel issues.

    No - the inability of the USA to reprocess nuclear waste is self-imposed
    by an act of Congress in 1978 at the behest of President Carter as has
    been discussed above.

    The idea behind the 1978 law was to dissuade Great Britain, France, and
    others from reprocessing nuclear waste - the USA leading by example.

    It didn't work!! Great Britain reprocesses waste at Sellafield on the
    Cumberland coast, and France reprocesses waste at LaHague - and
    continue to do so.

    In spite of the failure of the policy - the USA is still living with the
    consequences of this action. It complicates the design and licensing
    of our own disposal facilites [ ex. Yucca Mountain].

    Unfortunately, there appears to be no movement to reverse a failed policy.

    Dr. Gregory Greenman
    Physicist LLNL
     
  19. Oct 14, 2004 #18

    Morbius

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    In the early part of my career in the early 1980s, I worked for
    Argonne National Laboratory on the design of the IFR.

    The IFR does recycle its waste - and it does so "in situ" - on site - so there
    is no transport of fissile material outside the facility.

    For more information, consult the transcript of a PBS Frontline
    interview with my former boss, Dr. Charles Till at:

    http://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html

    Dr. Gregory Greenman
    Physicist LLNL
     
  20. Oct 28, 2004 #19
    EUREKA! Mt Saint Helen recently erupted, why not dump all nuclear waste into the volcano? N.waste will go down to the earth core and problem solved. :approve:
     
  21. Oct 29, 2004 #20
    Problem solved! Now on to what to eat for dinner...
     
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