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Power Supercomputing Technology Science

Self-Healing Ceramics for Nuclear Safety 45

Posted by timothy
from the now-with-fewer-pulsating-tumors dept.
Roland Piquepaille writes "Pacific Northwest National Laboratory (PNNL) researchers have used supercomputers to simulate how common ceramics could repair themselves after radiation-induced damages. This is an important discovery because 'materials that can resist radiation damage are needed to expand the use of nuclear energy.' These ceramics, which are able to handle high radiation doses, could improve the durability of nuclear power plants. They also might help to solve the problem of nuclear waste storage. But read more for additional references about how this research could improve nuclear safety."
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Self-Healing Ceramics for Nuclear Safety

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  • by Chabil Ha' (875116) on Saturday April 19, 2008 @09:29PM (#23131968)
    To replace the pottery my kids accidentally smash...
  • Helpful, but more so for disposal of nuclear waste than for nuclear plants. IIRC, most of the critical components that would see very high radiation over their lifetime have to be metal or plastic for other reasons. If a good portion of those pieces could be replaced by ceramics in all respects, this would be a great advance.

    For disposal and vitrification this would be a great advance. A huge element of uncertainty in the Yucca mountain facility comes from the caskets the waste is stored in. Ceramics wo
  • I am sick and tired of all the issues about super long-term storage. Far better AND cheaper to burn this up over a 100 years, then to pay the monster price of 10000 years of storage, and all the concern about it. OTH, these ceramics certainly sounds interesting.
  • Waste storage? (Score:5, Insightful)

    by momerath2003 (606823) * on Saturday April 19, 2008 @11:11PM (#23132494) Journal
    The only problem with nuclear waste storage is politicians. Radioactive waste storage is a proven, safe technology. Even so, long-term geological storage is not the right solution, since we would be throwing away a lot of good, fissionable material that can be recycled for energy production in, e.g., fast reactors.
    • by Protonk (599901)

      The only problem with nuclear waste storage is politicians. Radioactive waste storage is a proven, safe technology. Even so, long-term geological storage is not the right solution, since we would be throwing away a lot of good, fissionable material that can be recycled for energy production in, e.g., fast reactors.

      In a sense. In another sense, it isn't true. If you act like a true environmentalist and have a discount factor of zero (future generations are worth just as much to you as current generations), then it IS still a problem. Deaths due to groundwater leakage 1500 years from now would deter you from using a potentially unsafe storage facility.

      However, I don't understand why people are willing to damage the next generation while espousing concern for someone 10 generations from now. Global Warming will dis

      • Re:Waste storage? (Score:4, Insightful)

        by Chandon Seldon (43083) on Sunday April 20, 2008 @12:44AM (#23132808) Homepage

        If you get your fuel recycling going properly, then the cycle-end waste gets back to ore-level radioactivity in a couple hundred years. We have building technology that can reliably be trusted to store stuff for a couple hundred years - poured cement anywhere that isn't in a flood zone or on a tectonic fault line.

        It's only with this damn fool "recycling nuclear fuel gives the terrorists nuclear bombs" nonsense that we're stuck with dangerously radioactive material 1500 years from now.

        • by Megane (129182)

          It's only with this damn fool "recycling nuclear fuel gives the terrorists nuclear bombs" nonsense that we're stuck with dangerously radioactive material 1500 years from now.

          And we have none other than James Earl "Misery Index" Carter Jr. [wikipedia.org] to thank for that.

          • And yet, that was one of his very few bad decisions. All in all, the man had to do SHITLOADS of crap because nixon and ford had not. Both Nixon and Ford ignored the root of our MISERY problem and heaped loads of new regulations on. It was Carter who pushed oil and gas deregulation through to be applied in 1981. Nearly ALL of the inflation issue could be traced right back to republican choices. He even pushed airline deregulation which created the aviation boom that America, followed by the rest of the world
        • The fact fast breeder reactors just haven't proven as safe as water moderated reactors probably has something to do with it as well.

          There are coolants they can use for fast breeder reactors which don't result in a giant cluster fuck in worst case scenarios (lead and salt) but for the moment all the money and time has been put into liquid sodium ... which I wouldn't want in my backyard, or upwind in a couple 1000 km range.
          • Sodium has a couple of major advantages actually.

            For starters it is FAR less corrosive to steel than is water, lead or molten salt. Now since I suspect Monju will be mentioned again, yes a sodium fire can MELT the steel ( this is what happened at monju ), but in terms of chemical corrosion sodium is second only to helium. As per the Monju accident you're not going to have me believe the same accident would have been a non-issue had it used lead instead. Sure, the lead may have caused less damage to the stee
            • Since sodium is much lighter than lead it doesn't cause as much stress on the equipment. Since lead has a density of 11, even a modest system height of 10 meters would give rise to a coolant pressure of 110 atmospheres at the bottom of the system


              That is of course supposed to be 11 atmospheres. Typos always happen at the worst place...
              • by vrmlguy (120854)

                That is of course supposed to be 11 atmospheres. Typos always happen at the worst place...
                If only Slashdot offered some way to view a message before actually posting it.
            • I didn't say it doesn't have advantages, I'm sure it has major advantages ... most of them economic. What it doesn't have and never will have is as low a probability of meltdown as water moderated reactors or as low a severity of the results in the case of such a melt down. (This is usually disingenuously ignored when arguing for fast breeder reactors.)

              As for Pollonium in the lead ... could you give me some numbers? The probabilities of complete exposure of the primary coolants in the first place for both t
              • I didn't say it doesn't have advantages, I'm sure it has major advantages ... most of them economic. What it doesn't have and never will have is as low a probability of meltdown as water moderated reactors or as low a severity of the results in the case of such a melt down.

                Uhm, they already do. Sodium cooled reactors have demonstrated that they are able to safely shutdown even with complete loss of control over their instruments, failure of all cooling pumps, and simultaneous failure of all control rods. Th

                • The only likely way to break a containment dome is with shrapnel from an explosion. Whether or not that is likely enough to worry about with liquid sodium, meh ... if all I have to go on are instincts in that matter I will go with my own. Word's won't sway me in this matter, simulations and a proven safety record would (it doesn't do so hot on the latter, okay no explosion occurred in Monju ... but only because they got really lucky).

                  Leaks happen and water is everywhere.
          • what about molten salt or candu reactors? afair they can both go on spent lwr fuel.
    • I thought some of the recycling ends up meaning that they have a large quantity of material with a low level of radiation. IIRC, France recycles their material, but Scandinavian countries complain because they're upstream from where France dumps their slightly "hot" water from their nuclear recycling facility.
    • by bluephone (200451)
      Solution: Put the politicians in Yucca mountain with the waste.
    • With the long history of testing we know exactly how these materials will perform 1000 years from now.

      You suggest that recycling the fissionable material will eliminate, or greatly reduce, waste. Not so. The problem is that the fissionable material is only a very small percentage of the waste stream. Almost verything that has been through a plant is treated as waste. The bulk of this is low level waste with no recycling potential.

  • Other uses? (Score:2, Interesting)

    I'm wondering if this might have implications beyond use in nuclear reactors. One of the big concerns with a manned trip to Mars is long-term exposure to radiation while en-route. This means that any spacecraft you use will have to be shielded, or at least have a shielded compartment for use during periods of high solar activity.

    Ceramics make good radiation shields, and could be great for low(er)-weight shielding for spacecraft, especially if you can use a method like this to extend the lifetime of the sh
  • by BlueParrot (965239) on Sunday April 20, 2008 @04:24AM (#23133436)
    Out of the generation IV proposals it is probably the gas cooled fast reactor that will benefit the most from this.
    http://en.wikipedia.org/wiki/Gas_cooled_fast_reactor [wikipedia.org]

    One of the major issues with global warming is that the hydrogen used to produce amonia and subsequently artificial fertilizer, is currently derived from natural gas. The process emits a lot of CO2 , and it isn't really feasible to
    stop producing hydrogen as it could result in a collapse of agriculture due to drastically increased fertilizer prices.

    Two generation IV reactors, the very high temperature reactor, and the gas cooled fast reactor, are aimed to resolve this by dramatically improving the efficiency of electrolysis of water. This can be achieved through so called thermochemical hydrogen production ( http://en.wikipedia.org/wiki/Sulfur-iodine_cycle [wikipedia.org]), but it requires temperatures exceeding 800 C.

    While it is likely that thermal reactors with helium coolant ( such as the pebble bed reactor ) could achieve this, it gets more tricky for fast reactors. Fast reactors have about 100 times less waste, better uranium utilization and the waste decays to safe levels between 100 and 1000 times quicker than for thermal reactors. The main catch is that the MUCH higher power density and neutron flux makes it difficult to find suitable materials. Sodium coolant doesn't work for hydrogen production since it boils before reaching the necessary temperatures, lead has corrosion issues especially at high temperatures and its high mass density makes it difficult to find materials that are strong enough at the temperatures required. Helium works, but because it has a much lower heat capacity than molten metals the reactor would likely reach higher temperatures under accident scenarios, and thus materials that can withstand a very strong neutron flux at high temperatures is absolutely necessary for a gas cooled fast reactor to be feasible.

    • Re: (Score:3, Funny)

      by polar red (215081)
      All fine, but if you look at the actual cost of those too-complicated-to-be-ever-economical-systems, i have to wonder if they ever get marketed ... it will just be cheaper to go the wind/solar/electrolysis way, and certainly if they stop subsidizing nuclear so much.
      • Re: (Score:1, Flamebait)

        by BlueParrot (965239)
        a) They are likely to be cheaper than existing reactors due to a simpler plant layout.
        b) Nuclear is profitable many places where it isn't subsidized, in Sweden it is even taxed and still runs at a profit.
        c) Solar/Wind are subsidized more than nuclear ( in terms of money per kwh ) in virtually every country that use them to any large extent.

        To put it in terms of another poster, if Solar / Wind is so cheaper than nuclear (which is itself competitive with coal ), why isn't your house exclusively powered by the
        • Re: (Score:2, Informative)

          by polar red (215081)

          Solar/Wind are subsidized more than nuclear
          you are DEAD WRONG. look up who Insures nuclear power plants. look up the research costs, look up who pays for the instances who check the plants ... THAT is all also part of subsidy.
          • by polar red (215081)

            why isn't your house exclusively powered by them?
            next year, I will have cells on my roof.
          • Right, so France and Japan spending billions to research sodium cooled reactor technology is the reason water cooled reactors are profitable in Sweden ( despite being taxed ) while Solar is not? The money spent on research during the last 2 decades is to be considered a subsidy to the plants that were built 40 years ago ? Give me a break. As for the instances that inspect power plants do you seriously think these costs get anywhere close to that of the power plants? Heck, ok, I'll bite and let you add a 10%
              • Uhm, by those statistics Nuclear gets about 4 times the money of renewables despite contributing many many times more energy. I.e, when you consider subsidies per unit of energy generated, nuclear receives far less than renewables. What next, are we to pay the same amount for one wind turbine as for one nuclear power plant and then call the nuclear plant subsidized because you didn't spend any money on solar ?
                • by polar red (215081)
                  No, I say we drop _ALL_ subsidies. The problem with that of course, is that you can't get insurance for nuclear power plants.
            • Re: (Score:1, Flamebait)

              by polar red (215081)

              As for insurance, how many accidents have there been in the western world that resulted in a payout from this insurance?
              and what will happen when a serious nuclear meltdown occurs? who will pay for the damages and lives lost? I can bet it won't be the companies (see: chernobyl), but the government. Note : a serious meltdown WILL occur, cuts will always be made by managements, and NOTHING has ever been build that is 100% safe, 99,999% is NOT 100%.
              • By that standard we shouldn't build windmills or factories producing solar cells either. While one single windmill may not be much of an issue, you need thousands of them to replace a single nuclear power plant ( and a single nuclear plant can replace ALL solar cells currently operating in the world ). Now while it won't get as much media attention, people die working with windmills. Some fall down servicing them, people die during steel mining etc... Saying a major accident WILL occur, is about as useful t
    • what about lead coolant? afair there were some russian submarines with lead cooled reactors.
      • It could work, the problem is that if you want to use it for thermo-chemical hydrogen production you need to push temperatures above 800C. At those temperatures the protective oxide layers that prevent the steel from corroding dissolve into the lead coolant. Furthermore the steel itself starts losing its strength, which is a major issue if you use a heavy metal like lead. There is research into using ceramics and special metal alloys with silicon dispersed into its crystal lattice, but this is experimental
  • ... materials that are stopped from transforming into another because there in no room to move but will expand to fill small gaps where they exist. Interesting stuff but not a worldshaking new discovery since there are a few things like this.

    The most common ceramic of this type to be used for the past few decades is known as "partially stablised zirconia". Engineering students generally find out about it in the first year of their course if they have been educated in the last twenty years. It's cool and

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