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How to extract uranium from seawater for nuclear power (2017)

engineering.stanford.edu

11–20 of 55 posts

Re: How to extract uranium from seawater for nuclear power (2017)

#11
“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.

Re: How to extract uranium from seawater for nuclear power (2017)

#12
post #9
post #8

Earlier quoted context omitted.

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.

Several milligrams or kilograms?

According to Wikipedia(https://en.wikipedia.org/wiki/Uranium_in_the_environment):

"According to the United Nations Scientific Committee on the Effects of Atomic Radiation the normal concentration of uranium in soil is 300 μg/kg to 11.7 mg/kg."

So let's say 5mg/kg. 200kg of soil per gram. How much area do you need to make 200kg of soil if you're going down 1m? I'd guess not much...

So I think OP is wrong and it's more like 'several grams'.

Re: How to extract uranium from seawater for nuclear power (2017)

#13
> 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.

Re: How to extract uranium from seawater for nuclear power (2017)

#14
post #8

Earlier quoted context omitted.

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.

>> 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.

for a house in my neighbourhood I'd guess ~100 mg

Re: How to extract uranium from seawater for nuclear power (2017)

#15

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

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

Re: How to extract uranium from seawater for nuclear power (2017)

#16

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)

I'd rather have a teleporter than a jetpack. Jetpacks are loud and smelly. I'd rather just beam somewhere instantaneously, and go on with my day.

Re: How to extract uranium from seawater for nuclear power (2017)

#17
post #9

Earlier quoted context omitted.

Several milligrams or kilograms?

According to Wikipedia( https://en.wikipedia.org/wiki/Uranium_in_the_environment ): "According to the United Nations Scientific Committee on the Effects of Atomic Radiation the normal concentration of uranium in soil is 300 μg/kg to 11.7 mg/kg." So let's say 5mg/kg. 200kg of soil per gram. How much area do you need to make 200kg of soil if you're going down 1m? I'd guess not much... So I think OP is wrong and it's mo…

I first thought that OP estimate was way off, but from your numbers he may be right! If you only need 200 tons of soil for 1kg of Ur, that's not much.

A cubic meter of soil is ~2 tons, maybe more, which means you only need a 10m by 10m square to get 1kg of Ur if you go 1m deep. Wow.

Re: How to extract uranium from seawater for nuclear power (2017)

#18
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...

Re: How to extract uranium from seawater for nuclear power (2017)

#19
post #9

Earlier quoted context omitted.

Several milligrams or kilograms?

According to Wikipedia( https://en.wikipedia.org/wiki/Uranium_in_the_environment ): "According to the United Nations Scientific Committee on the Effects of Atomic Radiation the normal concentration of uranium in soil is 300 μg/kg to 11.7 mg/kg." So let's say 5mg/kg. 200kg of soil per gram. How much area do you need to make 200kg of soil if you're going down 1m? I'd guess not much... So I think OP is wrong and it's mo…

According to this[1] the weight for 1 cubic meter of dry soil is 1200kg, so 6 grams of uranium per cubic meter.

Looking at average suburban lot sizes, they seem to be about 7200 sqft , which is about 668m^2.

Which gives 668m^3 which gives about 4kg of uranium shockingly.

[1] https://www.reference.com/science/much-cubic-meter-soil-weig...

Re: How to extract uranium from seawater for nuclear power (2017)

#20
post #9

Earlier quoted context omitted.

Several milligrams or kilograms?

According to Wikipedia( https://en.wikipedia.org/wiki/Uranium_in_the_environment ): "According to the United Nations Scientific Committee on the Effects of Atomic Radiation the normal concentration of uranium in soil is 300 μg/kg to 11.7 mg/kg." So let's say 5mg/kg. 200kg of soil per gram. How much area do you need to make 200kg of soil if you're going down 1m? I'd guess not much... So I think OP is wrong and it's mo…

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