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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

#121

Post by [deleted] »

fc417fc802 wrote: post #116
XorNot wrote: post #86

Earlier quoted context omitted.

The short version is brine is weird: it's surprisingly resistant to diffusing and tends to flow more like an immisicible fluid. So you have to put quite a lot of effort into getting it to actually disperse rather then just fall to the seafloor.

That's silly, you'd mechanically mix it with seawater rather than wait for it to diffuse. The concern would be the volume of desalinated water extracted from the local region versus the flux from ocean current. As long as that ratio is acceptable there won't be any long term problem. Alternatively, in the absence of sensible regulations a cutthroat operator devoid of ethics constructs a plant that dumps concentrated…

[deleted]

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

#122

Post by card_zero »

tdb7893 wrote: post #25
Jblx2 wrote: post #21

Earlier quoted context omitted.

>Persian Gulf has 20% more salt in water because of the humans I would like to read more about this from an authoritative source.

Through the magic of Googling "Persian Gulf salinity" it seems like it's more that it's a shallow Gulf in a dry area so it has significant evaporation. Desalination does effect it but it's only a few percent of the total evaporation (which is still surprisingly big) and doesn't sound like the main driving factor or an imminent ecological concern. https://www.frontiersin.org/journals/marine-science/articles... https:/…

Huh, looks like they process about 1/500 of the water in it every year. So enough to make a dent in the salinity eventually.

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

#123

Post by technothrasher »

mmmBacon wrote: post #30
b0rbb wrote: post #22

Awesome, love seeing stuff out of Rochester - RIT or UofR or any of the nearby schools. Totally underrated area for academic pursuits.

UofR physic grad that also worked at the LLE here. Agree Rochester schools are underrated (although admittedly a little biased). At least in the sciences you have access to lots of opportunities you don’t have at bigger name schools. They set me up in life in a way that I don’t think would have happened elsewhere.

I had a great time at UR in the early 90’s because they had the most computing hardware per interested student in the country. I was able to relatively quickly work my way up to access to pretty much any system the school owned that I wanted, including the Cray at the LLE.

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

#124

Post by threwrfaway »

ceejayoz wrote: post #93
threwrfaway wrote: post #84

Earlier quoted context omitted.

You can dilute the brine in a facility before disposing.

Go on. With what?

...sea water. You take 10 units of sea water for every unit processed and you'll get a slight increase in salinity.

A phase diagram tells you exactly how far you need to go.

You know this makes more thermodynamic sense than carbon capture, right?

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

#125

Post by threwrfaway »

asdff wrote: post #117
ceejayoz wrote: post #93

Earlier quoted context omitted.

Go on. With what?

Seems like you could just dilute it with seawater at like 100:1 ratio and it would be negligible done offshore. We already dump our shit 5 miles out.

100:1 is overkill and energetically very wasteful. It's a fairly straightforward chemical engineering problem.

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

#126

Post by threwrfaway »

wlesieutre wrote: post #104
threwrfaway wrote: post #84

Earlier quoted context omitted.

You can dilute the brine in a facility before disposing.

With fresh water, we’ll get it from desalinization! Hey wait a second…

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.

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

#127

Post by threwrfaway »

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.

Actually it's easy and ok. Just mix it with the treated sewage right before it returns. Simple mass action implies the salinity hasn't changed.

But wait! There's water mass loss due to leaky pipes and outdoor pools!

Mixing salt water and brine is perfectly ok. Just use a phase diagram.

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

#129

Post by turkeyboi »

ceejayoz wrote: post #58
SoftTalker wrote: post #54

Earlier quoted context omitted.

The brine came from the ocean. So just dilute it back to close to ambient salinity using municipal waste water that you are discharging anyway.

> The brine came from the ocean. Sure, and enriched uranium comes from the ground, but that doesn't mean it's safe to dump it back in after the enrichment process! > So just dilute it back to close to ambient salinity using municipal waste water… Wouldn't it generally be easier to process that municipal waste water, as is already fairly common?

Enriched uranium is perfectly safe to dump but it would be stupid to do so. Fission products are nasty but uranium itself is not, comparatively.

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

#130

Post by aeonfox »

xyzzyz wrote: post #107
galaxyLogic wrote: post #105

Earlier quoted context omitted.

But more thermal storage you want more salt you want, and it's gotta cost something, right? https://en.wikipedia.org/wiki/Molten-salt_battery

If you read the article you sent me, you'll learn that, just as I said, you don't use sodium chloride, aka table salt, aka sea salt, for these purposes.

A better example are sodium ion batteries, which are about to take off in a big way

https://www.catl.com/en/news/6812.html

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