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

engineering.stanford.edu

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

#21

Post by macintux »

dylan604 wrote: post #16
epistasis wrote: post #4

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.

Or your clone goes on with their day.

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

#22

Post by epistasis »

mehrdadn wrote: post #5
epistasis wrote: post #4

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)

For anyone who hasn't seen these yet: https://www.youtube.com/watch?v=_VPvKl6ezyc Also see: https://www.youtube.com/watch?v=EAJM5L9hhBs

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

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

#23

Post by manfredo »

herdodoodo wrote: post #2

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 w…

I don't think the idea is that it's meant to be competitive against extraction on land. What it does do is expand the potential uranium supply to make nuclear power viable as a global power supply on the order of hundreds of thousands of years at least.

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

#25

Post by whatever1 »

herdodoodo wrote: post #2

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 w…

Things change, US itself has changed. Why do you expect Canada to lick the boot of Trump if they get the treatment they get today ? Why does one expect that an uranium cartel will not be formed the moment that it gains significant market adoption?

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

#26

Post by eloff »

manfredo wrote: post #23
herdodoodo wrote: post #2

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 w…

I don't think the idea is that it's meant to be competitive against extraction on land. What it does do is expand the potential uranium supply to make nuclear power viable as a global power supply on the order of hundreds of thousands of years at least.

It also gives a path to nuclear power and weapons for counties with no uranium deposits.

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

#27

Post by titzer »

denkmoon wrote: post #24

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

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.

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

#28

Post by wtallis »

aaron695 wrote: post #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 mi…

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.

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

#30

Post by throw_away »

kosievdmerwe wrote: post #19
01100011 wrote: post #12

Earlier quoted context omitted.

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...

I thought the numbers from wikipedia looked a little shaky, maybe. I couldn't find those specific numbers in the reference UN PDF.

Google says soil concentration of Uranium is like 3ppm. But, if you do the math, 668 x 1200 x 1000 x (1/1000000) = 802g for every ppm. 3ppm Uranium would be 2.4kg by this number.

Lead is at like 15-40ppm (https://ag.umass.edu/soil-plant-nutrient-testing-laboratory/... ), so between 12 and 32 kg of lead in everyone's back yard?

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