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A Clever New Approach To Desalination
jbeaupre writes "The Economist reports on progress by a company called Saltworks on using saline gradients to do the heavy lifting of desalination. In essence, Saltworks uses solar energy or waste heat to concentrate sea water. They then use the ionic gradient between the concentrated brine and two sea-water streams to pull ions from from a 3rd sea-water stream. It appears to work with entropy by trading the reduced entropy of the desalinated water against the increased entropy of 'mixing' the brine and the other sea-water streams. The article only discusses Na and Cl, but even just removing these ions is a step in the right direction."
Thinking about desalination makes me remember that episode of "The Voyage the Mimi" in which they used the process to make drinking water:
http://video.google.com/videoplay?docid=-524069894840499801# (A/V's not synced)
Freedom is drinking a beer in the park when you're supposed to be at work.
Yeah, pretty much, for all practical purposes, but not quite, because sooner or later the fucking sun will in fact burn out.
You didn't need to read TFA. It's in the summary. Second sentence.
# cat
Damn, my RAM is full of llamas.
what if they collected the fresh water vapour that is evaporating off the salt water as well?
I'm guessing this would require active refrigeration unless they're in a colder climate?
TFA is a bit light on details: why do Na+ ions go to one stream and CL- to the other? Have they got membranes that are impervious to CL- and NA+?
Yes. From TFA:
OK between this and the General Fusion guys http://www.generalfusion.com/ Canada has got water and energy completely licked. http://www.saltworkstech.com/ OK actually I'm still trying to run the numbers on the both of them (and waiting for some peer reviewed publications.)
Dr. Flammond: "A year ago, I was close to perfecting the first magnetic desalinization process. So revolutionary, it was capable of removing the salt from over a million gallons of sea water a day! Do you realise what that could mean to the starving nations of the earth?"
Nick Rivers: "My God, they'd have enough salt to last forever!"
E pluribus unum
Electricity is the flow of charge, not electrons.
If your statement was accurate, your computer would not work as it depends upon semiconductors which function in part based on the flow of positively charged holes in the electron structure of the material. (see p-n junctions, etc.) The Hall effect can be used to verify the charge of the moving carrier within a current. It can be either positive or negative.
Note that this desalinization mechanism works very similarly to a fuel-cell which also involves ion flow as part of an electric circuit.
Other than the fact that they are consuming not producing energy, yeah exactly like that...
Yeah, pretty much, for all practical purposes, but not quite, because sooner or later the fucking sun will in fact burn out.
Or get bought out by Oracle after giving away all its energy for Free.
When information is power, privacy is freedom.
Comment removed based on user account deletion
The key piece of the work is an ion bridge. This has to permit the travel of one kind of ion but not the other, i.e. Na+ or Cl-. Looks like this material could be expensive. It might plug up need to be periodically replaced. How expensive these are? How non toxic these are? What is needed to manufacture them? These are the questions we need to ask.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
T
Laws are horrible moral guides, moral guides make even worse laws.
No, it's not inaccurate, unless you're claiming that protons don't have a charge. The ions here are nothing like wires. In a wire, the atoms (nuclei and nonconductive electrons) are fixed in position while the conduction band electrons are free to move from atom to atom. But in this desalinization process, the nuclei themselves actually move -- that's what makes it desalinization. The sodium and chlorine ions are true charge carriers. Ion conduction is not uncommon. Here's some more info on that:
http://amasci.com/amateur/elecdir.html
Visit the
And we could freeze a bunch of it and ship it to the poles.
I prefer rogues to imbeciles because they sometimes take a rest.
It doesn't in my terrarium.
You do not know what you are talking about. An ion is an atom (or group of atoms) that have more protons than electrons. Maybe you should spend a few hours on wikipedia boning up on your basic chemistry.
A stream of alpha particles would have a well-defined current, despite the lack of electrons.
Be that as it may, atoms are not ions, which is what the attempt at an article states.
The article doesn't state that atoms are ions. Rather, it states that ions are electrically charged atoms, which is totally correct. Here is the exact quote, in context:
I don't find any incorrect statement in the above quote regarding ions.
True. Too bad greenhouses are impossible.
THL phish sticks
I'm fairly certain that the oil industry has a particularly good understanding of plate tectonics; the term "fossil fuels" isn't lost on them.
So if this is the future...where's my jet pack?
No. It does look a bit similar but it isn't. In reverse osmosis the water has to pass through the membrane, driven by high pressure pumps, leaving its impurities behind.
In this version the impurities pass through the membrane (two separate membranes in fact) driven by an electrical current. Cleverly, the electrical current itself is generated by the salt passing through other membranes out of the highly concentrated brine that you made in your solar ponds.
(to the music of Queen) - Black-bottomed pool you make the salty ions get found!
Sorry, couldn't resist
War as we knew it was obsolete
Nothing could beat complete denial
- Emily Haines
The winter in Poland is already plenty cold enough...
:-P
Cheers,
"What in the name of Fats Waller is that?"
"A four-foot prune."