
How to extract uranium from seawater for nuclear power (2017) - forgot_my_pwd
https://engineering.stanford.edu/magazine/article/how-extract-uranium-seawater-nuclear-power
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herdodoodo
Uranium is not the only element/mineral of interest that is dissolved in
seawater. Research has been done on this stuff before. I'm glad it's being
done, but unfortunately this will remain unviable when compared to open-pit or
underground mining (even accounting for the risk of depending on foreign
suppliers + transportation costs of importing).

The biggest reserves are in Canada and Australia, not really countries we have
to worry about cutting off supply anytime soon. We have bigger strategic
mineral concerns (REMs and China)

Cool tech, won't leave the lab. Just like the billion "metal-ion/air/water"
batteries that get shilled non-stop.

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sandworm101
>> The biggest reserves are in Canada and Australia, not really countries we
have to worry about cutting off supply anytime soon.

Unless you are Iran. North Korea. Or anyone else currently not able to buy
uranium from Canada.

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pfdietz
Uranium is quite common, if you don't care too much about cost. If you own a
house with a suburban lot, the top meter of soil in your yard probably
contains several kilograms of uranium.

~~~
sandworm101
>> the top meter of soil in your yard probably contains several kilograms of
uranium.

No. That is way way off. Grams ... more likely milligrams and even that sounds
too much.

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akiselev
According to [1], "the normal concentration of uranium in soil is 300 μg/kg to
11.7 mg/kg." According to [2], the density of topsoil ranges from 1,100 to
2,500 kg/m^3. One acre is about 4,000 m^2, so a conservative estimate is that
there is about 1.3 kg of uranium in 1 meter of top soil on a 1 acre lot. (4000
m^3 * 1100 kg/m^3 * 3x10^-7). That's just the low end - taking the midway
point for both yields over 40kg (4000 m^3 * 1800 kg/m^3 * 6 mg/kg).

[1]
[https://en.wikipedia.org/wiki/Uranium_in_the_environment](https://en.wikipedia.org/wiki/Uranium_in_the_environment)

[2]
[https://structx.com/Soil_Properties_002.html](https://structx.com/Soil_Properties_002.html)

~~~
masonic

      on a 1 acre lot
    

Not many of us have all of an acre lot for our homes.

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akiselev
According to [1], 2 billion people are subsistence farmers with under 5
hectares. The population adjusted average seems to be around a quarter of a
hectare (~0.6 acres) _per person_ (which sounds low to me, as someone who has
grown my own food without automation).

10^9 == many of us. Unless your definition of "us" is hacker news readers.

[1]
[https://en.wikipedia.org/wiki/Subsistence_agriculture](https://en.wikipedia.org/wiki/Subsistence_agriculture)

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Krasnol
Related:

Nuclear Power Worldwide: Development Plans in Newcomer Countries Negligible

* An analysis of current decommissioning and new construction projects reveals a downward trend in nuclear power worldwide

* Only four newcomer countries are currently constructing nuclear power plants and all are plagued by financial difficulties and delays

* An econometric analysis suggests that countries classified as potential newcomers tend to be less democratic

* On the supply side, the dominant driving force is the geopolitical interests of countries that export nuclear power

* Within the relevant international organizations, Germany should work to ensure that no support is given to the construction of nuclear power plants in newcomer countries

[https://www.diw.de/documents/publikationen/73/diw_01.c.74261...](https://www.diw.de/documents/publikationen/73/diw_01.c.742611.de/dwr-20-11-1.pdf)

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jws
Aluminum is 1000 times more abundant in seawater than (edit)uranium. Lithium
is about 60 times as abundant. With uranium at $32/lb, aluminum at $0.75/lb
and lithium at $6/lb it seems that aluminum and lithium would reach commercial
viability first.

Magnesium has already made it with significant production coming from
seawater.

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AnimalMuppet
I don't think your first sentence says what you think it does...

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elihu
“Concentrations are tiny, on the order of a single grain of salt dissolved in
a liter of water,” said Yi Cui, a materials scientist and co-author of a paper
in Nature Energy. “But the oceans are so vast that if we can extract these
trace amounts cost effectively, the supply would be endless.”

That's a lot more uranium than I would have guessed. According to the top few
google results, it's about 3 milligrams per cubic meter.

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epistasis
Great, now can anyone build a reactor that will be cheaper than solar +
batteries?

Problems like these make me think of jetpacks or flying cars. It turns out
that the future isn't what we thought it would be from the sci-fi ideas of the
mid 20th century. It's a lot cooler in some ways, and far far more boring in
others. (I want my jetpack)

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mehrdadn
For anyone who hasn't seen these yet:
[https://www.youtube.com/watch?v=_VPvKl6ezyc](https://www.youtube.com/watch?v=_VPvKl6ezyc)

Also see:
[https://www.youtube.com/watch?v=EAJM5L9hhBs](https://www.youtube.com/watch?v=EAJM5L9hhBs)

~~~
epistasis
These are incredible and I hadn't seen them, thank you!

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aaron695
> How to extract uranium from seawater for nuclear power

“Concentrations are tiny, on the order of a single grain of salt dissolved in
a liter of water”

This sounds way to much, I can boil a litre of water in the kitchen and have a
grain of Uranium?

From Yahoo answers

Grain of Salt - 2.25 mg (.00008 ounces).

Uranium - 3 micrograms per liter (0.00000045 ounces per gallon)

Yahoo answers didn't have how much energy 3 micrograms of Uranium can create.

I'd guess if we could get a way to extract it with an algae or something, the
energy(sunlight) it uses would be better off stored and burned.

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wtallis
Going based on numbers from Wikipedia, U-235 is good for 83.14 TJ/kg, but that
isotope only has a natural abundance of 0.72%. So 3 micrograms of uranium in
the natural proportions would get you around 1800 J ignoring any contribution
from other isotopes (ie. you're not using a breeder reactor). That means your
uranium extraction method needs to be very energy efficient indeed.

~~~
acidburnNSA
Oh yeah, you pretty much have to use breeder reactors to use seawater uranium.
That has been the plan all along, e.g. Cohen 83:
[http://large.stanford.edu/publications/coal/references/docs/...](http://large.stanford.edu/publications/coal/references/docs/pad11983cohen.pdf)

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econcon
Anyone who comes with Thorium reactor, India will gladly supply their Thorium
for your power requirement provided you give them working Thorium reactor.

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PopeDotNinja
Illinois EnergyProf just did a video on Thorium power. I enjoyed it.

[https://youtu.be/5zJ7fuRPmxc](https://youtu.be/5zJ7fuRPmxc)

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justatdotin
thats a lot of water to pump. I notice they don't mention a cost: spot price
for U remains low, and renewables cheaper.

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caymanjim
Who said anything about pumping water? As far as I can tell, this is meant to
be a passive collection system.

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denkmoon
How does one enforce nuclear non-proliferation if any country can extract
uranium from seawater?

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titzer
Uranium enrichment to a suitable level is a seriously involved industrial
process that requires thousands of supersonic centrifuges to do at scale. This
is not something that flies under the radar easily. It's also very energy
intensive to run those centrifuges, so it's difficult to conceal.

~~~
PopeDotNinja
Illinois EnergyProf has a video I enjoyed on uranium enrichment.

[https://youtu.be/z8mUCBG49N8](https://youtu.be/z8mUCBG49N8)

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anonu
Article from 2017. Also not very informative IMHO about how this process
actually works

