Energy From Thorium Discussion Forum

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PostPosted: Aug 12, 2012 11:45 am 
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I've been reading a bit about the Coles Hill deposit of uranium in southern Virginia. There is an estimated 54,000 metric tonnes of U3O8 in two ore bodies there that are situated on about 200 acres of land.

Aerial image of mining site

Cross-section of underground ore body

If that uranium was enriched to HEU (~93%) with a 0.2% tails fraction, then it would have a feed-to-product ratio of 183 to one, and the 54,000 tonnes of uranium would contain almost 300 tonnes of HEU product.

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If that was used to start LFTRs, it could bring roughly 300 GWe of power online, which would thereafter be sustained only by thorium.

On the other hand, if the uranium deposit is processed into LEU at an enrichment level of about 4%, with the same tails fraction, then the feed-to-product ratio is 7.45 and the 54,000 tonnes would make about 7200 tonnes of fuel for LWRs. Each GWe of LWR consumes about 35 metric tonnes of fuel each year, so the deposit would fuel about 200 GWe-yrs of LWRs.

The spent fuel of the LWRs would contain some low levels of U-235, about 1%, and plutonium, fission products and transuranics. The plutonium could be removed chemically, consumed in a fast spectrum reactor with a thorium blanket, and U-233 could be formed, which could then be used to start LFTRs.

Virginia Uranium

NY Times: A Big Uranium Deposit, and a Big Debate on Mining It


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PostPosted: Aug 12, 2012 11:59 pm 
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Plan B
Have the SNF reprocessed by the French or the Russians. The reactor grade plutonium could be used directly in the LFTR or via fast reactors.
Plan C
Use 20%LEU and thorium in existing LWRs.
http://www.dae.nic.in/writereaddata/.pdf_38
You could have 20%LEU driver bundles or bundle cores. Reprocess thorium pins or bundles for U233. Convert the irradiated thorium bundles to chlorides and separate by fractional distillation.


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PostPosted: Oct 22, 2012 4:45 pm 
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Should a Virginia Family Be Allowed to Mine the $6 Billion in Uranium on Its Own Land?


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PostPosted: Oct 28, 2012 10:46 pm 
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As I understand it, right now uranium mining is illegal in Virginia. It's a shame, really.

I also wonder about the ore body: Apparently it's an igneous intrusion which contains a somewhat high concentration of uranium. I believe Rod Adams said that there may be similar geologic formations elsewhere in Virginia. To be honest, I don't know about that. The geology at that site seems pretty unique.


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PostPosted: Dec 16, 2013 9:56 am 
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Drive to mine uranium in Virginia comes to quiet pause

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A company is suspending its campaign to mine one of the world’s largest known deposits of uranium ore in Virginia, concluding that Gov.-elect Terry McAuliffe’s opposition presents a significant challenge over the next four years.


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PostPosted: Dec 16, 2013 11:07 am 
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Ned Speirs wrote:
As I understand it, right now uranium mining is illegal in Virginia. It's a shame, really.


It's the sad story of nuclear power in general around the world: its illegal in most countries. Not just mining. Many countries lump nuclear plant or mine construction in with murder and rape. Even the legal system has been scared out of its wits and gets nuclear wrong. As if a uranium mine is more dangerous than a bauxite mine.

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I also wonder about the ore body: Apparently it's an igneous intrusion which contains a somewhat high concentration of uranium. I believe Rod Adams said that there may be similar geologic formations elsewhere in Virginia. To be honest, I don't know about that. The geology at that site seems pretty unique.


What do you mean? Igneous intrusions usually contain uranium. Granite is the best example - there's always uranium in it and higher concentrations are not uncommon.


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PostPosted: Dec 31, 2014 1:00 am 
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Cyril R wrote:
What do you mean? Igneous intrusions usually contain uranium. Granite is the best example - there's always uranium in it and higher concentrations are not uncommon.


IN oxidizing conditions uranium is soluble in water. Because there's oxygen at the surface of the earth, any uranium at the earth's surface washes away (especially in a wet climate like Virginia). In the case of this particular ore deposit, the igneous intrusion changed the chemistry of the rocks, so that now the rocks are in a reducing environment. So, the uranium did not wash away.

You're assuming that the intrusion is the ultimate source of the uranium. I'm not sure that's the case.

I really don't know whether it's a granite intrusion or some other type of intrusion. If it's a gabbroic intrusion the igneous material would be depleted in uranium.

Even if it were a granite intrusion, the concentration of uranium in granites (while higher than in gabbroic rocks) is still too low to be economically extracted.


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PostPosted: Jan 01, 2015 7:41 pm 
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It just demonstrates the problems in mining for more uranium. Thorium may face a similar fate. There was resistance to processing Australian rare earths in Australia and Malasia due to thorium content. My repeated stress on reprocessing the used fuel should be seen in this context, and not in the narrow view of current costs. As in the case of the UK and France in the past, there will be people to reprocess the used fuel. Once you get to thermal or fast breeders, the nuclear fuel is inexhaustible. India is continuing to work on thorium due to perceived paucity and high cost of local uranium. However those holding stocks of reprocessed or depleted uranium could go for uranium breeders, solid or MS fuel.


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