Re: I'm hearing bad things about breeder reactors

From: Eunometic (eunometic_at_yahoo.com.au)
Date: 06/12/04 

Date: 12 Jun 2004 05:23:20 -0700

dezakin@usa.net (Dez Akin) wrote in message news:<dd43b4da.0406110034.2d3f2a74@posting.google.com>...
> "Eunometic" <eunometic@yahoo.com.au> wrote in message news:
> <ChZxc.1133$sj4.1070@news-server.bigpond.net.au>...
> > "brianb" <bri1600bv@hotmail.com> wrote in message
> > news:68a6629.0406090711.701863fd@posting.google.com...
> > > eunometic@yahoo.com.au (Eunometic) wrote in message
> > > news:<e935396a.0406081726.2b818661@posting.google.com>...
> > > > bri1600bv@hotmail.com (brianb) wrote in message
> > > > news:<68a6629.0406080759.931460d@posting.google.com>...
> > > > > They're saying that they could never work out the kinks
> > > > > and that they are incredibly expensive etc.
> > > > >
> > > > > Are breeder reactors in general more expensive than non
> > > > > breeders, if they CAN work out the kinks?
> > > > >
> > > > > Does anyone know what the current status of research and
> > > > > such is?
> > > > >
> > > > > Is it only breeder reactors that can burn plutonium?
> > > > > Or is the idea that by turning U238 into plutonium
> > > > > in a breeder that this plutonium
> > > > > can be burned elsewhere? I guess I'm confused about the
> > > > > difference between "breeder reactor" and "reprocessing".
> > > > > Anyone know? Thanks in advance.
>
> Breeder reactors suck now because uranium is dirt cheap, we have
> working designs for light water reactors that are competitive, and
> designing new reactors carries significant capital risk. The
> opportunity cost is too high given the price of uranium.

The differences in cost would as a percentage be relatively small.
It's not a doubling in price, more like 25% or so and ultimetly would
be less if the world shifted to a nuclear economy and the price of
uranium rose or as the economies of scale developed.

>
> > > > All of the breeder programes were cut short of their full
> > > > development and test cycle as instigated.
> > > > The IFR for instance was cut down by
> > > > Jimmy Carter of political reasons not technical or
> > > > economic ones.
>
> Thats not to say technical or economic reasons didnt exist. If they
> did, the market would be running breeders.

They are substantialy commerical. Ever tried certifying a new reactor
type or obtain investment funding for developing one? Then are the
political ones.

>
> > > > The Japanese even offered to continue funding the research.
> > > > The IFR was very proliferation resistent becuase the
> > > > pyro-processing can't produce pure plutonium and never left
> > > > the reator building however the fear was that such reactors
> > > > would ultimetly spread the abillity of other countries to
> > > > produce bombs.
> > > >
> > > > Yes there concerns relating to corrosion reistence of
> > > > materials but saying that there are problems that need to
> > > > be solved is not the same as saying that those problems
> > > > are difficult to solve. For instance you can't test
> > > > the corrosion resistence of various alloys and
> > > > materials unless you actualy have a program to test
> > > > them by exposure
> > > > to real conditions.
> > > >
> > > > The IFR (integral Fuel Reactor) was fueled with a
> > > > mixture of enriched
>
> IFR is integral fast reactor. Its a fast neutron reactor and generally
> fast neutron reactors are an excuse to make Pu239. Whats integral
> about it is that the fuel is reprocessed on site, not in the reactor.

Becuase reprocessing is integral to the power plant and becuase the
fuel cycle in integral.

>
> > > > uranium. Over its life the U235 would be fissioned for energy
> > > > while the U238 would convert into Plutonium at a rate faster
> > > > than U235 was used up. The fuel would occaisionaly be
> > > > partialy removed and 'pyro-processed' in the reactor building
> > > > itself (eliminating a security issue) and returned to the reactor.
> > > > As a result the IFR only needed one fueling in its entire
> > > > life. During pyroprocessing the 'actinides' were removed
> > > > and returned to the reactor in a seperate
> > > > part where their decay would provide energy and where
> > > > high flux neutrons would destroy the actinides.
>
> Pyroprocessing isn't about that... its just replacing the aqueous
> reprocessing technique with the molten salt electrorefining. You still
> have security concerns; its not proliferation resistant, you have to
> pull the fuel out of the reactor. Every solid fuel reactor has this
> issue.

Pyroprocessing simply can;t be used to make weapons grade material.
Becuase it is carried out on site there are no security of transport
issues.

Finaly making uranium out of breeder fuel is effectively impossible.
The Russians tried, the British tried the USA tried. You need a
special weapons reactor to make the fuel. The isotobes of plutonium
are too hard to seperate for one.

>
> > > > Becuase the actinieds were destroyed by 'transmutation' the IFR
> > > > did not produce long term waste. IE the volume and activity of waste
> > > > is drasticaly reduced.
>
> You can do the same thing with aqueous reprocessing... IFR is
> different in that the fuel rods are metallic instead of oxides, and
> molten salt electrorefining is theoretically cheaper. Of course you
> need at least an epithermal neutron spectrum to incinerate actinides,
> which LWR doesnt supply...

Quite, though the pyroprocessing/electroregining process is not quite
so ameanable to producing pure plutonium.

>
> > > > Becuase the IFR needed such little fuel and even produced more
> > > > than it used the japanese calculated that they could absorb
> > > > all the uranium they needed into special polymer membranse
> > > > suspended in the sea. While the Uranium would be expensice
> > > > the price of electricity would be
>
> Seawater uranium is totally orthoganal to breeder reactors, except
> that if getting U from seawater is inexpensive enough, it makes
> breeding uneconomical for some time.

Increasing the price of uranium by a factor of 10 would barely effect
electricity price putpit by a breeder.

>
> > > > hardly effected. They calculated that this would given mankind
> > > > millions of years of energy.
> > > >
> > > > The French reactor 'super phenix' had some problems with tube
> > > > welds and has only been opperated small amount of time.
> > > > It was restarted recently for some transmutation experiments.
> > > > The IFR can never have that problem becuase it has the fuel
> > > > in tubes suspended in to molten sodium pool rather than the
> > > > other way around.
>
> Ah, yes... the other problem with the IFR facility... sodium cooling.
> Just what you want, a positive void coefficient with most entirely
> prompt neutrons. I'm afraid if you must have a liquid metal fast
> reactor, the lead-bismuth way is the way to go.
>
>
> > > Thanks for your reply. Did the IFR ever get to a point where it
> > > could be made for commercial use? I know they had a plant in
> > > Idaho, I read an interview with the guy in charge. I think
> > > Clinton finally put the nail in the coffin.
> >
> > I believe it got close. You need to build test plants and after that
> > pilot plants. There are a lot of practical things to learn. The
> > Molten Salt reactor also got close but it had corrosion problems. A
> > lot of the issues relate to the reactors breeding but not breeding
> > enough but overall the consensus is that these reactors are very
> > feasible.
>
> IFR was never 'close' to anything. It was a research testbed for a
> variety of technologies all shoved together into one package. In that
> sense it was very successful.
>
> The MSRE facility was far closer to being a commercial design. The
> corosion problems faced were mostly dealt with with hastelloy and the
> tritium migration issue was also dealt with. Really it won't get close
> for a long time because waste disposal isn't much more than a
> political issue, and uranium is so damn cheap.
>
> > There are VHTGR (Very Hight Temperature Gas Reactors) that are
> > breeders. One of the more intersting cycles is the molten lead
> > breeder. They can be built up to any size but if kept down to below
> > 200MW they can be be built as a self contained capsule that is sealed
> > at the factory. The complete unit is shipped and then runs for 20
> > year with no intervention completely on passive cooling. It is then
> > switched of for a while and shipped back to the factory for disposal.
> > the Russians have a lead bismuth one. A chap called Greenspan is
> > trying to build one in the USA. Then there are the thermal breeders
> > that don't need fast neutrons. There are neutron beam pumped
> > breeders.
> >
> > There is quite literaly dozens of viable ways of building breeders.
> > almost to many to choose from.
>
> The only one that is close to being economically competitive is a
> molten salt breeder. You need to have online reprocessing to make it
> competitive, and that means fluid fuel. The rest of them are
> interesting research testbeds, and have their niches, but the best way
> for doing breeding is the critical MSBR. Negitive void coefficient,
> mostly delayed neutrons, thermal expansion of the fuel lowers the
> reactivity, inexpensive online reprocessing removes the nastiest of
> the neutron poisons, high core temperatures that yield high
> thermodynamic efficiency, and economic analysis that indicate that its
> about as competitive with coal fired plants today, more competitive
> than LWR's.
>
> The fast neutron reactors have inertia because they were originally
> designed with one purpose in mind: breed Pu239. MSR's (and every
> thermal breeder) aren't good at that.
>
> The only reactor technology I like better than MSR's are the
> nonexistant fissioning plasma core reactor ideas... if we could find a
> way to make sure the plasma flourides don't eat away at the reactor
> core vessel. Maybe the fusion plasma physics guys should redirect
> their efforts for a while.

Relevant Pages

  • Re: CANDU reactor questions
    ... plutonium from elsewhere (such as dismantled nuclear weapons) they ... energy needs using various fuel sources in which a U-235-only fuel cycle ... These aren't *all* uranium reserves, because they consider, as usual, only ... doesn't happen in reactors using fast neutron reactor ...
    (sci.energy)
  • Re: Being eyeballed
    ... of RTG fuel. ... There are reactor operating regimes ... Enriched Uranium isn't. ... AIR the nominal cost of a kilo of fuel-rod grade uranium metal is about ...
    (alt.sysadmin.recovery)
  • Re: Disposing of nuclear waste.
    ... work out the energy required to get payload to hit the sun. ... by the Uranium in a power reactor in the first place. ... First is natural Uranium prospecting. ... do quite well for non-molten spent fuel rods encased in ceramic. ...
    (sci.physics)
  • Re: Nuke waste and reprocessing
    ... >>burned off as MOX. ... >>civilian power reactor fuel already sitting in repositories and more ... It IS being done with weapons Pu to some extent but many reactor operators ... that of conventional uranium oxide fuel. ...
    (sci.energy)
  • Re: How Africas desert sun can bring Europe power
    ... usually jumped to the consideration of breeder reactors because of the ... "shortage" of uranium fuel. ... one must swap out the fuel ... BN-600 fast reactor in Russia have generated almost 100 billions ...
    (sci.energy)
Loading