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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

#181

Post by redsocksfan45 »

numpad0 wrote: post #159
redsocksfan45 wrote: post #131

Earlier quoted context omitted.

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.

That's the dormant plant. Rokkasho-mura plant is officially incomplete for decades, doing tests and upgrades without actual production. If you think otherwise and you're not wrong, and I think you ARE not mistaken since this isn't the first time someone other than myself mentioned it here, that means they're making bombs because we in Japanese public aren't told about it. There has only been just some routine comment…

[dead]

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

#182

Post by rapnie »

lightedman wrote: post #47
xyzzyz wrote: post #44

Earlier quoted context omitted.

Brine is very easy to dispose of: you just pump it back to where it came from. Solid crystalline salt, on the other hand, is a hassle.

"Solid crystalline salt, on the other hand, is a hassle." Just make prettier-than-Himalayan salt lamps out of it and sell it to hippies. Easy solution.

That only shifts the problem. Now we need an increased supply of hippies that are hard to come by in a low hippie-tolerant environment.

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

#183

Post by FartyMcFarter »

ceejayoz wrote: post #180
FartyMcFarter wrote: post #163

Earlier quoted context omitted.

Why is it akin to that? Doesn't the salt come from the sea in the first place?

A more apt comparison than you realize. Most of the carbon we spew into the atmosphere came from the air. Ancient plants took it in via respiration.

That still doesn't make it a good comparison. The salt emitted by desalination plants is already in the sea now, it's not salt that went somewhere else.

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

#184

Post by Ekaros »

xp84 wrote: post #145
asdff wrote: post #119

Earlier quoted context omitted.

There are salt mountains lining most midwestern freeways as it is for winter.

I just realized that future archaeologists will be tracing our roads using the salt residue!

Actually I have been thinking about this. Surprisingly straight and long cuts in rock formations might be a real thing to track. In at least some places at least some rock blasting is preferred to get aggregate for road foundations. And these tends to be rather straight and rather steep.

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

#186

Post by threwrfaway »

wlesieutre wrote: post #133
threwrfaway wrote: post #126

Earlier quoted context omitted.

Sarcasm aside, your comment actually works: you can use the freshwater from desalination! Just wait for the saltwater to come back around in the sewer.

Globally about 70% of freshwater is used for agriculture so less than a third of it will come back around, if it's exclusively for residential/commercial use you might do better but overall not a strategy that balances out

70% of desalinated water wont ever go to agriculture because its too expensive to use for corn. Only very high value crops need apply.

But, so what? 30% sewage is still a strong dilluant... especially when mixed with more seawater

Im shocked how many people cannot grasp that you can dilute brine's salinity arbitrarily close to seawater's with energetically cheap pumps.

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

#187

Post by iberator »

ceejayoz wrote: post #48
xyzzyz wrote: post #44

Earlier quoted context omitted.

Brine is very easy to dispose of: you just pump it back to where it came from. Solid crystalline salt, on the other hand, is a hassle.

> Brine is very easy to dispose of: you just pump it back to where it came from. Easy, but not necessarily good for the spot you're pumping concentrated salt back into.

that's 200% bullshits. Countries that invested into desalination plants are known to create death zones right where brine is sent back - even if miles from the coast

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

#188

Post by KaiserPro »

jmward01 wrote: post #50
Animats wrote: post #29

The paper: [1] They're still at lab scale in glass. They haven't built a usable system, even a small one. The big claim here is that it doesn't clog; capillary action moves the salt out of the active area to another area, where some yet to be developed mechanism removes it. That needs to be demonstrated. If they can come up with something that runs for years without clogging or replacing the active material, that's a…

This is an interesting tech, but I have big doubts. In the picture you can see some salt coating the surface. Even just a little seems like too much for this type of system. I really hope they can make this work and scale this up.

The crucial part is that pressure from the capillary action pushes the concentrated brine out onto the non capillary area. unlike fabric the area isn't enclosed so cleaning is easier if the salt starts to accumulate.

Obviously it needs to be cleaned regularly otherwise the salt encroaches into the sensitive bits. However the cleaning method doesn't require dissolving, just scraping.

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

#189

Post by KaiserPro »

LogicFailsMe wrote: post #34

So crazy question: take a dehumidifier, attach some solar panels, and deploy at scale for non-potable water suitable for crop irrigation anywhere that isn't a desert. Does it work? And if not, why?

Yield depends on humidity, which varies according to region and season.

It also requires more infrastructure to get yield. In theory all you'd need to have is these etched metal plates, a transparent dome and a source of briny water. (and a cleaning mechanism)

The etched plates creates 100% humidity (probably more as it'll condense out)

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

#190

Post by iamjs »

ashdksnndck wrote: post #95
ceejayoz wrote: post #48

Earlier quoted context omitted.

> Brine is very easy to dispose of: you just pump it back to where it came from. Easy, but not necessarily good for the spot you're pumping concentrated salt back into.

If you use fat pipes that go a decent distance from shore, diluting your brine with ocean water, you’ll have a negligible impact on the ocean. The problem is if you dump lots of brine in shallow waters. Old designs did have that flaw, but it’s not that difficult to design around this constraint now that we know about it. IMO this is an issue where NIMBYs are using environmental concerns as a smokescreen to block new…

The city of Corpus Christi, TX is currently considering options for desalination plants—all of which pump their brine into the shallow water inside the bay or the ship channel.
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