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M.A.I.N.B.

Massive Array of Isolated Nuclear Batteries, or A Much Safer Fission Reactor
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Currently, most nuclear reactors are massive groupings of fuel assemblies in only a few vessels... Three Mile Island had thousands of fuel assemblies "burning" at a time, so there could be millions of individual uranium pellets in one reactor at a time.

This is dangerous. When a tremendous amount of fuel is used within a single vessel for one massive reaction, the radiation level in the core is incredibly high, and it only takes one failure to cause a catastophre.

It's also unnecessary. If you take 2 fuel pellets and squeeze 'em together hard enough to alter the density, a small fission reaction occurs. The heat output typically reaches only slightly above the boiling point of water. Because the size of the reaction is so much less, the radiation emissions are miniscule, and get immeasurably small with distance in only yards from the reaction.

what if we were to encase small reactions in individual, tiny cases, and use massive amounts of these. Because each reaction is isolated from the other, Only the heat output grows and not the radiation levels. Run these all on a single coolant system, and drive turbines like always.

To get an idea of why this works, think of Cadmium, a heavy metal which is quite toxic to humans.

A fair amount of it is present in a Nickle-Cadmium rechargeable battery, as suggested by the name. But if you break one open, although it may make you sick, it probably will not kill you, and it is unlikely to affect anyone else. Now think of a tank of cadmium-laced water. It holds the same amount of cadmium as, say, 2000 batteries. If it breaks, it will make a lot of people sick and may kill quite a few of them.

Finally, consider those 2000 batteries. If one breaks, it does not affect the others, so they hold just as much cadmium much more safely.

That's the idea here... if one unit fails, it doesn't affect the others and cause a major catastrophe.

This design has the extra benefit of being easier to maintain and fuel, since each of the cells has its own radiation shields. You can replace them individually, rather than refuelling the entire reactor at once. Best of all, it produces precontained waste!

clothist, Oct 21 2003

Nuclear Powered Aeroplane http://www.halfbake...0powered_20airplane
<Insert Description Here> [suctionpad, Oct 04 2004]

Small Nuclear Reactors http://www.adn.com/...4182p-4226215c.html
[PiledHigherandDeeper, Oct 04 2004, last modified Oct 21 2004]

Pebble bed reactor http://web.mit.edu/pebble-bed/
[dbsousa, Oct 04 2004, last modified Oct 21 2004]

[link]






       Yah, this is the main problem with all these ideas...   

       We made such a mess of things by doing it wrong in the past that we a.)Don't have the money to do it right. b.)Will have one heck of a time getting said money, since the public has had such bad experiences with nuclear technology in the past.   

       People hear the word "nuclear" or "atomic" or even "nucleics" and just freak out. :P
clothist, Oct 21 2003
  

       In order to keep the reaction going long enough to make it worthwhile, you must have a minimum amount of mass available for the nuclei to hit.
RayfordSteele, Oct 21 2003
  

       Something here makes me think this is bad science, but I'm too dumb to figure out what.   

       Didn't there used to be a programme to develop small nuclear reactors (e.g. for a nuclear aeroplane). If these very small "nuclear batteries" were possible, I would have thought they would have at least tried them.
suctionpad, Oct 22 2003
  

       Yes, there have been programs to develop small reactors. The problem here is, the energy output from a single battery is fairly small when compared with larger reactors. Also, you've still got to worry about cooling systems, and so on. The main bulk of the reactor is in the "secondary" systems. "massive array" is in there for a reason.   

       // In order to keep the reaction going long enough to make it worthwhile, you must have a minimum amount of mass available for the nuclei to hit //   

       2-4 pellets should be enough, if squeezed to high densities.
clothist, Oct 22 2003
  

       //The heat output typically reaches only slightly above the boiling point of water.//   

       So everyone can have a nuclear powered kettle?
suctionpad, Oct 22 2003
  

       // So everyone can have a nuclear powered kettle? //   

       Once again, that's not really the idea here, I'm suggesting a bloody huge group of those things on a single cooling system. But, yes, if you have plenty of money and space for shielding, fuel, and waste storage, I suppose you could use a single one to make a nuclear powered ketttle.   

       maybe you could save money by using custard instead of heavy water?
clothist, Oct 22 2003
  

       Have you looked at "pebble reactors?" (No time for link now, find later...)
Detly, Oct 22 2003
  

       This is a bit like a PBMR actually. Yep. I'd not quite call it baked though. Not really fair since, you know, they aren't really in mass production yet. Good thinking though.
Madcat, Oct 22 2003
  

       I wasn't implying any sort of bakedness, but I thought [clothist] might be interested. If I recall rightly, one was used to power an inner city building somewhere in Japan...?
Detly, Oct 22 2003
  

       This is a brilliant idea. Like many brilliant ideas, though, the kids at MIT are working on it already. They call it a pebble bed reactor (link) The idea is that no individual pebble gets hot enough to melt its lead casing, but gets more than hot enough to boil water...
dbsousa, Nov 04 2003
  

       Thank you for finding that link. :)
Detly, Nov 04 2003
  
      
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