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New method turns ocean water into drinking water, without waste

rochester.edu

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Re: New method turns ocean water into drinking water, without waste

#221

Post by rtpg »

ajb wrote: post #4

There is a fundamental minimum amount of energy needed to desalinate: you can't take less energy to do it,than you could gain back (from osmotic pressure) if you allowed the desalinated water to expand a cylinder containing the residual brine. This is large. This paper is a thermal method, so it doesn't have an electricity input, but to justify their efficiency claim, they should really compare against what you could…

This is a weird angle I think? Desalination brine is a real problem, so if you can eliminate that then efficiency is less of an issue (especially given that desalination plants are often in places with a lot of sunlight!).

You don't want to be super duper inefficient but "no waste that has to be dumped back out" feels really big to me

Re: New method turns ocean water into drinking water, without waste

#222

Post by rtpg »

xp84 wrote: post #146
cyanydeez wrote: post #90

Earlier quoted context omitted.

yeah, if you like to kill everything in a few 100 feet radius and kill some more in the zone of reliance. this is delusional ecological

So, we could just dump it on the salt flats in Utah? Plenty of places are already super salty, so nothing lives there (unless it’s able to handle that).

[dead]

Re: New method turns ocean water into drinking water, without waste

#223

Post by pfdietz »

redsocksfan45 wrote: post #131
numpad0 wrote: post #97

Earlier quoted context omitted.

Japan is also barred from doing own enrichment, being a non-nuclear state. Though, there nevertheless is a dormant set of requisite facilities.

You're wrong. Japan does do their own enrichment, 150k SWUs at Rokkasho with plans to bring that up to 500k SWUs a year soon. If they chose to make.bombs instead of fuel, they could make dozens a year.

They also have a large stockpile of reactor grade plutonium. Not the best material for bombs, but workable.

Re: New method turns ocean water into drinking water, without waste

#224

Post by gaiagraphia »

AlexandrB wrote: post #112
gaiagraphia wrote: post #88

Earlier quoted context omitted.

I love projects like this. A shame the west has handed over the baton to the Chinese and Saudis when it comes to actually being daring with megaprojects. Some over stuff whhich are cool to read about: Redirecting Siberian rivers into Central Asia https://en.wikipedia.org/wiki/Northern_river_reversal Redirecting Congo basin rivers to replenish Lake Chad https://en.wikipedia.org/wiki/Lake_Chad_replenishment_projec... F…

The Saudis aren't "daring" with megaprojects. They're fucking[1] stupid[2]. Saying their megaprojects are "daring" is like saying I'm "daring" for claiming I'm going to build a catapult that will launch me to the moon. [1] https://en.wikipedia.org/wiki/Trojena [2] https://en.wikipedia.org/wiki/The_Line,_Saudi_Arabia

I wonder how many times the UK and USA had to 'be stupid' to achieve some of their best achievements?

When curiosity gets replaced by bureaucracy and regs, you know a civ is dead..

Re: New method turns ocean water into drinking water, without waste

#225

Post by haritha-j »

SimplyUnknown wrote: post #171
haritha-j wrote: post #33

Earlier quoted context omitted.

Indeed, it’s the same university that gave us room temperature superconductors.

Huh? That was University of Utah/Brigham Young University right. That is, if you're referring to Pons and Fleischman.

I was referring to this scandal: https://www.nature.com/articles/d41586-024-00716-2

Re: New method turns ocean water into drinking water, without waste

#227

Post by trumpdong »

mycall wrote: post #226

Nature desalinates seawater all the time in the form of water vapor without using electricity. There must be another way for humans to command and control the release of fresh water out of the ocean for our own needs.

There is, but it takes plenty of energy in one form or another. Nature has the advantage of scale. One kilowatt per square meter over the whole oceans.

Re: New method turns ocean water into drinking water, without waste

#228

Post by Enginerrrd »

lazide wrote: post #220
Enginerrrd wrote: post #201

Earlier quoted context omitted.

That’s been a solved problem, engineering-wise, for a while. The advanced treatment stages take care of it. Between UV, ozone, and nanofiltration, etc. we can remove the pharmaceuticals. Actually the problem is the water comes out too pure out of a well designed water reuse system, to the point where the mineral content can be too low and you need to add some back in.

Cite for it being solved? All the articles I can find have it as ‘active and growing problem with some potential mitigations which are not universally applied’. All the recycled water systems I’m aware of still have PCC issues and excess ion contamination problems too still.

Admittedly my knowledge was based on work I did in academia, and I now work in transportation, so I suppose it’s possible I’m in error, but I’d be surprised if much survives the RO stage, and isn’t eaten up by the oxidation stage. My understanding was that the water needs to actually get remineralized to protect the distribution system. And that it’s very devoid of pharmaceutical contaminants by that point. I was unaware of this being an issue in real world potable reuse systems. Though, I suppose different jurisdictions may have different standards. My state was pretty strict.

Re: New method turns ocean water into drinking water, without waste

#229

Post by pchristensen »

Nifty3929 wrote: post #106
pchristensen wrote: post #72

Earlier quoted context omitted.

It's such a good book! Like any dad reading history, I have been annoying my family for years with fun facts I learned in that book. David McCullough's other books like The Great Bridge (about building the Brooklyn Bridge) are also great.

You and I are the same person apparently. Let me tell you about malaria! Or the bends! Or tetanus! Please! Wait, where's everybody going?

Did you know that IBM got its start building the control center for the Panama Canal locks? Did you know that lobbying has been the same since at least the 19th century? That 10% of all of France's population invested in their canal company, but the company was too afraid to tell the people that Panama wasn't flat like the Suez Canal area? And... and... and...

Re: New method turns ocean water into drinking water, without waste

#230

Post by noripcord »

card_zero wrote: post #89
noripcord wrote: post #85

Earlier quoted context omitted.

no, just take the water, remove the salt & minerals. Over time it'll dilute. Water falls again in the form of rain, obviously, but not the salt. You're not worried? If it's for batteries? For sure they'll extract whatever they can.

Right, remove the salt and minerals. We don't need that much salt, so we'd have to build pyramids or something with it. We drink the water, but then it ends up back in the oceans. The reason I mention that part is because if it didn't, if we could destroy the water, then the remaining water would retain the same salinity, and the concern would be that we drain the ocean dry, which is silly (I refer you back to how bi…

I get it. The thing to me is, though, how do you know whether extracting some amount of minerals is irrevocably gonna change the ecosystem for some species or not? If it changes it badly for some, then a chain reaction can of course alter something important.

Can it be, for some species, like changing the formula of the atmosphere's air for us?

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