New Nukes? 3

[Zogzog]

What is the latest news on building new nuke plants in the US? Last I heard there were several licences issued mostly for the mid atlantic area.

I was a navy nuke but went into the HV power system testing field and have been considering entering back into the nuke world. I am also considering a move to the mid atlantic area.

 

[hydrae]

mauner

Breeders require reprocessing,
The manufactured fuel (Plutonium or Thorium), is from the edge of the core and require the removal of the fission products from the atoms that fission-ed instead of absorbing the neutrons. The fission products poison the core just like the do in all other reactors and requires new fuel on a regular basis from the reprocessing plant.

If we reprocessed fuel, like the rest of the world, all the long lived stuff (trans-Uranium elements) are sent back to the reactors for use as fuel, all the short lived stuff have half lives less than 30 years, turn that into glass and in 300 years you have got a interesting piece of glass. Why do we need 10,000 year storage then? All spent fuel can be reprocessed; heavy water, light water, graphite moderated, gas cooled, sodium cooled breeders, even submarine and aircraft carrier cores.

No reactor can blow up like an atom bomb, bombs are made from 99.9% +/- fission grade material, typical reactors use up to 5% fission grade material, breeders use up to 20% fission grade material in the central core. that is still a far cry from 99

As for blowing up; accident scenarios are from pressure, steam and chemical reactions with the complications of radiological contamination, not from short order prompt supercriticality events which is what atom-bombs do.

I will step down from my soapbox now

Hydrae

 

[vpl]

Mauner has some of the terminology wrong; however, that doesn't make him entirely incorrect. The only breeder reactor ever licensed for construction (Clinch River) was designed to use fast neutrons[\u] to bombard a core of reprocessed fuel(as stated by hydrae.) If I am remembering correctly, the reactor design had a positive coefficient of reactivity. This meant that, if the moderator went away, the reactor would increase in power, rather than decrease --unfortunately, somewhat similar (but not identical!) to the Chernobyl design. This would not cause the reactor to blow up, but could make a meltdown more likely. I would also like to mention that Chernobyl had safety systems to prevent a reactivity excursion, but that the operators bypassed them to run an experiment.

However, reactor design has come a long way since the 1960's, and if one were to be built in the US today, it would need to meet the NRC's requirements (which, despite being a moribound agency, does not do rubber-stamping, no matter what anti-nuclear activists claim).

I would like to point out to Mauner, that reprocessing was not always "illegal" in the US and, just a one President decided to not permit it, another President could allow it.

However, is any of this really work-related?

Patricia Lougheed

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[hydrae]

Fermi unit I was also a breeder

Hydrae

 

[electricpete]

Clinch river and Fermi were "fast water breeder reactors". These were the only two of that type and the Clinch river never completed.

http://www.sciam.com/article.cfm?id=how-do-fast-breeder-react

The U.S. constructed two experimental breeder reactors, neither of which produced power commercially. The Enrico Fermi Nuclear Generating Station in Michigan was the first American fast breeder reactor but operated only from 1963 until 1972 before engineering problems led to a failed license renewal and subsequent decommissioning. Construction of the only other commercial fast breeder reactor in the U.S., the Clinch River plant in Tennessee, was halted in 1983 when Congress cut funding. Elsewhere in the world, only India, Russia, Japan and China currently have operational fast breeder reactor programs; the U.K., France and Germany have effectively shut down theirs

Shippingsport PA had the first "light water breeder reactor". I assume if it was not one of the fast water breeder reactors, then it must have been a slow (thermal neutron) reactor.

http://www.asme.org/Communities/History/Landmarks/Shippingport_Nuclear_Power.cfm

The design effort had been redirected to peace-time power generation from a large-scale light water reactor for a proposed aircraft carrier. Constructed to advance nuclear fission technology in general, the plant was flexible in accommodating cores of different types. Various manufacturers with different designs and materials for components were used. Water in the primary system, heated by nuclear fission, flows to the heat exchanging system, which absorbs the heat. This heat turns water in the secondary system, a relatively low pressure system, to steam. This steam is sent to the turbine generator to drive the turbine.


The first power at Shippingport was produced on December 18, 1957, and was fed into the grid for the Pittsburgh area. On December 2, 1977, the first U.S. light water breeder reactor went to full power at Shippingport.

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[electricpete]

Correction: "These were the only two of that type in the US"

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[electricpete]

Wish I had an edit button. The paragraph about aircraft carrier core was not relevant to breeder reactors. I read somewhere that the Shippingsport reactor was originally intended as an easy backfit for existing reactors.

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[sldwrksrobotics]

The French have two significant reprocessing plants, but I was unaware that they are using any breeder reactors. Can someone clarify, I was under the impression they were reprocessing spent nuclear fuel from their LWR's

 

[electricpete]

In the first quoted text of mmy 31 Oct 08 9:38, it states the French have shut down (terminated) their breeder program.

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[hydrae]

Wiki has detials of reprocessing at the following link
complete with a list of sites, operating capacity, and periods

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

Hydrae

 

[unclesyd]

The French also process some German Nuclear Waste. You will notice that Germany is shutting all it's reactors down so they will have to burn coal.

http://news.theage.com.au/world/police-break-up-german-nuclear-protest-20081111-5lw7.html