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PostPosted: Dec 09, 2008 10:29 pm 
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arcs_n_sparks wrote:
Axil wrote:

IMHO, Lawrence Livermore lab picked the wrong country or at least the wrong government. It is not a coincidence that MVLIS comes from an Australian company. Like the IFR, proliferation fears makes the US decision makers irrational in the same way that some environmentalists are dead set and beyond reasoning against nuclear power.

Today, MVLIS is allowed in the US because MVLIS is more resistant to proliferation. Only a small amount of U235 enrichment is possible in the material flow because of intentionally low laser performance.

AVLIS, on the other hand, produces pure isotope. For U235, that is dangerous because of both proliferation and criticality danger.


First, Hargrove is no longer at LLNL. Hargrove had proposals in to use AVLIS to mine the tails from the GDPs; a clear winner. Next, mix in the politics of zero congressional support for LLNL versus the other districts that would benefit from other enrichment approaches (advanced centrifuges) or the status-quo. The last uranium runs at AVLIS were pretty impressive. There were some material issues that needed to be resolved for sustained performance.


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Next, mix in the politics of zero congressional support for LLNL versus the other districts that would benefit from other enrichment approaches (advanced centrifuges) or the status-quo.


It sounded like the cancelation of the AVLIS effort was a hatchet job, but the real reason was more nugatory then I thought.

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There were some material issues that needed to be resolved for sustained performance


No doubt, working with 3000C uranium vapor must be a real challenge. Some SiC and diamond like coating might help that though. We will need that for the fluorine.

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The last uranium runs at AVLIS were pretty impressive.



If Lftr ever gets government backing or at least approval, we might be fortunate enough to get access to the AVLIS technology rights that Lawrence Livermore lab developed for a bit under $700,000,000 and then discarded.


Thanks for your information and your insights.

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PostPosted: Dec 09, 2008 11:36 pm 
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Lars wrote:
Equilibrium uranium isotropic composition for a 1 GWe fast reactor is: 4700kg 233U, 1750kg 234U, 555kg 235U, 549kg 236U, (and 0.4kg 237U and 1.3kg 238U). We generate 20kg additional 236U per year (1000kg 233U) * (0.1 absorb in u233) * (0.2 absorb in 235U) = 20kg.

If we process the entire fuel volume in one year we need to process 2.3 liters/hour = (20m^3)(1000 liters/m^3)/365 days / 24 hours. This would reduce our TRU content 25x but won’t eliminate it. So we still would need to do back end TRU recovery.

Any 233U or 234U that leaks into the waste flow is similar to TRU wastes. To get performance similar to 0.4% TRU leakage (with a 10 year cycle) we have to do leak less than 260grams/GWe-yr. So we would need to isotropically isolate the 236U to contain less than 1% 234U+233U. The 235U we would prefer to leave in the fuel but leaking some of it to waste isn’t a major issue. We lose one neutron for each atom of 235U shipped to waste but I would guess we will still win neutronically if we extract the 236U.

The most aggressive TRU processing claimed 4e-6 leakage, to match this performance one would need 0.001% leakage.

So, I think the requirements on U236 extraction is pretty severe - someplace between 1% and 0.001% leakage and processing 2.3 liters per hour. The leakage rate probably means multiple passes through – lets call it 8 passes with no justification. The current processing of 1 liter per 100 hour for a single pass for 100kg. So crudely we would need to scale up the processing about 50x = (2.3l/hr)/(1l/100hr)(20kg/100kg) .

Is there a chance this technology can do this? It seems much harder than the U enrinchment process that is their main target.


The order of magnitude cost for AVLIS isotope extraction in year 1990 dollars is about $4,000 per kilogram for 5000 kg/year size plant.

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Is there a chance this technology can do this? It seems much harder than the U enrinchment process that is their main target.

Laser isotope separation cannot meet your requirement. Any of the LIS techniques can only achieve a maximum of 90% purity. Therefore, it cannot meet the purity standards that you have set.


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PostPosted: Jan 11, 2009 9:04 pm 
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Hello all... I read up on AVLIS back in my school days but it was my feeling at the time that the technology was too dangerous from a proliferation standpoint.

Recently I've been thinking about AVLIS from a purification standpoint because I imagine you could use lasers to purify just about any substance - separating argon from air for example. I had a few questions I'm hoping for some help with.

I was wondering if anyone knew what the current estimated SWU costs for AVLIS are? A basic search indicates $20-30/SWU but these numbers are rather old. What are the MLIS/SILEX costs? Are the SWU costs relatively independent of the feedstock parameters?

Does anyone know if separation has been tried in the liquid phase?

Thanks for any help.

P.S. I've read that AVLIS has also been been used to enrich gadolinium, lead and medical isotopes. Does anyone have AVLIS cost information for materials besides uranium?


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PostPosted: May 05, 2009 7:32 am 
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Interesting background to the story...I hadn't realized that laser isotope separation had gotten the centrifuge project killed:

NY Times: A 'robust' new fuel supply for nuclear power plants is emerging

Quote:
Nearly everything had changed since President Reagan canceled the $3 billion centrifuge program on the fateful day of June 16, 1985. Then, the United States was by far the world's leader in nuclear-generated electricity. It dominated the world market in the enriched uranium fuel that nuclear power plants 'burn' to make steam and then electricity. But Reagan and his advisers were smitten with a more futuristic technology, one that used lasers to solve the enrichment problem, which requires separating the power-producing isotope of uranium -- called U-235 -- from its close cousins in uranium feedstock.

By 2001, much of the U.S. nuclear industry was in shambles or being sold in pieces to foreign companies. U.S. dominance of the world nuclear fuel market had begun to wane. The U.S. Department of Energy concluded that laser-isotope separation wasn't commercially feasible. And a number of experts had begun to convince the Bush administration that a "nuclear renaissance" was needed, both for U.S. energy independence and to show other nations a plan to reduce greenhouse gas emissions.

Rogers, a stocky engineer who was present at both the death and the rebirth of the U.S. centrifuge, still recalls the "extreme shock" in 1985, when 2,500 employees at work here on the centrifuge project were told that its budget was canceled. He also remembers when the experts reached the conclusion in 2001 that the United States should make another try. Most of the men in the room who knew much about the centrifuge program were in their seventies.


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PostPosted: Jul 01, 2009 9:19 am 
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THIRTY MONTHS to review a license application for a commercial enrichment plant !

....mind you, this is just for LEU production :lol:


Quote:
GE’s uranium enrichment venture still on track
By Jim Brumm, StarNews Correspondent
Tuesday, June 30, 2009

GE’s uranium enrichment venture has completed its license application to the U.S. Nuclear Regulatory Commission, staying on schedule with its efforts which are expected to bring more than 500 construction jobs to Castle Hayne as early as 2012.

Global Laser Enrichment – a business venture of nuclear power plant builders GE and Hitachi, and uranium miner Cameco – announced Tuesday completion of the venture’s license application seeking the NRC’s approval to build the world’s first commercial uranium enrichment facility to use laser technology.

When the NRC formally dockets, or accepts, the application GLE submitted Friday, the regulators will begin a review the agency expects to complete in 30 months.

If approved, the facility to be built at GE’s Castle Hayne site will employ up to 300 in permanent engineering and support staff positions to produce a new domestic supply of enriched uranium to power nuclear plants.

Pointing out GLE was “on time” with its filing with the NRC, Chief Executive Tammy Orr said the company is on schedule to complete the enrichment test loop now under construction at Castle Hayne this summer. The test loop is designed to confirm the commercial feasibility of the technology and advance the design of the equipment, facility and processes for the planned production facility.

GLE’s statement explained it will use the information from the test loop in its evaluations of whether to proceed with the full-scale commercial facility.

Plans call for the plant to be co-located with the existing nuclear fuel manufacturing facilities of Global Nuclear Fuel, which will use enriched uranium as a raw material.

Also on the site are the new plants and services business of GE Hitachi Nuclear Energy.

The promise of the new enrichment facilities resulted in former Gov. Mike Easley’s announcement last summer that GE Hitachi would receive about $25.7 million in state incentives over 10 years if the company invests up to $900 million in the plant and hires hundreds of workers. New Hanover County also is providing $10 million in incentives spread over 12 years.


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