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New Nano Desalinization Method

ScuttleMonkey posted more than 8 years ago | from the favorite-buzzwords dept.

216

lbmouse writes "The Technology Review is reporting that researchers at the Lawrence Livermore National Laboratory have announced a way to use carbon nano-tube technology to reduce the cost of desalination of ocean water by 75 percent over current methods of reverse osmosis. From the article: 'The technology could potentially provide a solution to water shortages both in the United States, where populations are expected to soar in areas with few freshwater sources, and worldwide, where a lack of clean water is a major cause of disease.' The technology may also lead to new ways of eliminating carbon dioxide emitted from power plants."

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Nano (0, Offtopic)

dg41 (743918) | more than 8 years ago | (#15527685)

Wow, the iPod Nano can desalinise water? Wow, is there anything Steve Jobs can't do? Oh... wait. Nevermind...

Do Not Eat iPod Nano (2, Funny)

iamacat (583406) | more than 8 years ago | (#15528300)

Then you won't have to desalinize it

Perfect (5, Funny)

Who235 (959706) | more than 8 years ago | (#15527688)

Now, as sea levels rise, we can just drink it up.

Woo-Hoo!

Re:Perfect (3, Funny)

dubmun (891874) | more than 8 years ago | (#15527784)

Nah, we'll just piss it back out and then all the coastal cities and towns will be swimming in urine. I guess this is already the case in New Orleans...

Re:Perfect (1)

lthown (737539) | more than 8 years ago | (#15527785)

dang it, that was my comment - it's a perfect solution to the rising sea levels associated with global warming.

Re:Perfect (1)

alshithead (981606) | more than 8 years ago | (#15527846)

Who drinks water? Mmmm...beer....

Re:Perfect (3, Funny)

InsaneLampshade (890845) | more than 8 years ago | (#15527952)

*insert comment comparing American beer to water here*

Wow, 75% cheaper (2, Funny)

ENOENT (25325) | more than 8 years ago | (#15527691)

Just think of the patent licensing fees they can charge!

stop watering your lawn (2, Insightful)

Anonymous Coward | more than 8 years ago | (#15527692)

If your short of drinking water in the US.. stop watering your lawn...

Re:stop watering your lawn (1)

955301 (209856) | more than 8 years ago | (#15527722)

How does not watering my lawn from a well affect my drinking water shortage?

Re:stop watering your lawn (2, Insightful)

SatanicPuppy (611928) | more than 8 years ago | (#15527815)

You have a magic well that's not connected to the same water table that everyone in your area uses? Screw nanotech, patent the magic well! That and some magic beans and you could change the world!

Hate to break it to you bud, but it's all the same water in the end. There was a paper company that opened up east of here, and on the day that they commenced operations private wells for 50 miles around dried up, and who got hurt? People who had seen no reason to care because their water was totally different from the water that the paper company was slurping up a million gallons at a time.

Re:stop watering your lawn (0)

955301 (209856) | more than 8 years ago | (#15527883)

but but but, the watershed in my yard isn't in the water shed for the reservior. So my drinking water isn't the same as my water table. And what's more, suggesting that I should stop using water for the plants on the land so I can drink it is a little different from a paper mill drinking up the water.

nice dramatic response though - I was almost scared that you had a point.

I live in north atlanta ga, so the water comes from lake Allatoona - north of me and higher than me. It's the whole water pressure/dam thing.

Re:stop watering your lawn (1)

SeattleGameboy (641456) | more than 8 years ago | (#15528072)

but but but, the watershed in my yard isn't in the water shed for the reservior.

How do you know?

Most watersheds are hundreds feets down, and most areas share the same water system. Even if it is not your watershed, it may flow to another watershed down hill from you. Anyway you look at it, using valuable resource like water to keep non-essential items like grass green, is huge waste of resource.

Where does the lawn water go? (4, Insightful)

Latent Heat (558884) | more than 8 years ago | (#15528352)

I think the argument the lawn-waterers are making is that if they pump water out of the ground and sprinkle that water back on the lawn, most of that water will percolate back through the soil back into the ground water. Whether that argument holds up or not depends on such factors as the rate of transpiration and evaporation off the grass, whether the runoff water percolates back into the ground water reservoir or runs off somewhere else. That paper mill may be sucking the water out of the ground and then discharging it in polluted form in a stream, thus depleting the water table.

I am hard pressed that anyone living where there is normal rainfall for growing grass (i.e. Georgia) and has a water table high enough to tap with a private well isn't simply recycling the water by pumping it from below and discharging it on the surface. In fact, ground-source heat pumps are the next big thing in saving energy resources -- some of the systems are closed loop with a coil to pipe in the ground, other systems are open loop, lifting water from a well and discharging it on the surface. The various state DNR's that issue permits for such open loop systems want you to discharge on the surface -- they certainly don't want you pumping water that you have handled directly back into the aquifer without being filtered through the ground.

I agree that lawn watering is a serious use of resources in the desert Southwest U.S. You can be Fremen in your view of lawns on Arrakis, but to argue the same point on Caladan is stretching matters a bit far.

Re:stop watering your lawn (0, Troll)

modecx (130548) | more than 8 years ago | (#15528079)

You live in Devner, don't you? Some moron geologists keep trying to tell us that the Denver Basin and other aquifers in the system will last 10000 years or so at our projected growth rate, and that we'll just have to drill really deep wells! And that explains why they won't let many farmers in the Denver basin area withdraw water to irrigate their crops...

I suspect that their projections might include such fun things as bird flu, California falling off the map, or thermonuclear war, or maybe even the possibility that The Pope will finally start endorsing birth control!

Re:stop watering your lawn (2, Insightful)

pembo13 (770295) | more than 8 years ago | (#15527765)

But, but. How will the lawns be green???

Re:stop watering your lawn (4, Informative)

BigCheese (47608) | more than 8 years ago | (#15528065)

That's easy. Zoysia [wikipedia.org] . That's what I've had for years and I never water. Rain is pretty irregular here in Kansas too.
Plant a lawn that works with your local climate. It's better for the environment and better for the household budget.

Re:stop watering your lawn (1)

Bryansix (761547) | more than 8 years ago | (#15528151)

If your short of drinking water in the US.. stop watering your lawn...

Let me guess. You live in Northern California and you hate all those "water stealing bastards" to the south.

Great... (1)

drinkypoo (153816) | more than 8 years ago | (#15527693)

...when can I buy one? This would be an ideal upgrade for an awful lot of people. I have a RO water filter right now, not for desalination but for cleaning up drinking water that's just undrinkable, like the stuff in Marysville, CA. The thing's not all that huge, but it's sizable. (At least the size of an Xbox 360!) :D It would be great to have a tiny portable RO filter.

Re:Great... (0)

Anonymous Coward | more than 8 years ago | (#15527731)

It only costs $10 million. But on the plus side you will now have 100,000 gallons of fresh water a day.

Huge boon to hydrogen economy? (3, Interesting)

RingDev (879105) | more than 8 years ago | (#15527885)

Think of the other ramifications, one of the huge problems with cracking hydrogen from water is getting pure enough water to start with. If you can cut the cost of desalination significantly, you can reduce the total cost of hydrogen production.

-Rick

If it involved boiling the water... (5, Funny)

i kan reed (749298) | more than 8 years ago | (#15527698)

We'd probably call it vaporware

If it involved doing the anus... (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#15527928)

We'd probably call it gaymanlove

captcha:reformat

End Our Wet Drought! (2, Interesting)

aslate (675607) | more than 8 years ago | (#15527702)

This could solve all the UK's problems with our current drought! An island nation, somehow surrounded by water, it sounds like it could be a great way to give us plenty of water to drink.

Although Thames Water fixing all the leaks could also be a huge help...

Re:End Our Wet Drought! (1)

ToxikFetus (925966) | more than 8 years ago | (#15527779)

An island nation, somehow surrounded by water

Are you being incredulous, ironic, or incredibly stupid?

Re:End Our Wet Drought! (1)

Xichekolas (908635) | more than 8 years ago | (#15528166)

Or maybe just incredibly ironic... those sneaky islands and their surrounding waters!

Re:End Our Wet Drought! (0)

Anonymous Coward | more than 8 years ago | (#15527978)

The UK wouldnt have a water problem if they didnt have yobs with lowered Renault Cleo's with spinner exhausts and pink seatbelt pads being washed and polished every 2nd day of the week before a car park cruise.

Mandatory "Top Secret" reference (5, Funny)

CrystalFalcon (233559) | more than 8 years ago | (#15527707)

- Do you realize what this would mean to the starving nations of the planet?

- WOW! They'd have enough salt to last forever!

That's nice (0)

Mr.Fork (633378) | more than 8 years ago | (#15527710)

But how about a nanofilter for SPAM!!!

Re:That's nice (1)

Spy der Mann (805235) | more than 8 years ago | (#15527862)

But how about a nanofilter for SPAM!!!

You mean this one [stanford.edu] ? (PDF) Or perhaps you would like a more proactive method [okopipi.org] ? ;-)

And after the shameless plug, someone mod parent off-topic :P

right (0)

Anonymous Coward | more than 8 years ago | (#15527713)

have announced a way to use carbon nano-tube technology to reduce the cost of desalination of ocean water by 75 percent over current methods of reverse osmosis.

i'll bet they're ignoring the cost of the nanotubes themselves, which are like a bajillion dollars.

Re:right (1)

russ1337 (938915) | more than 8 years ago | (#15527795)

>i'll bet they're ignoring the cost of the nanotubes themselves, which are like a bajillion dollars.

but they are soo small?? How can they be that expensive? are they made of of the same stuff as iPods?

Re:right (1)

Spy der Mann (805235) | more than 8 years ago | (#15527910)

How can they be that expensive? are they made of of the same stuff as iPods?

Yes. Protons, neutrons and electrons. :P

Re:right (1)

Jon Luckey (7563) | more than 8 years ago | (#15528162)

How can [nanotubes] be that expensive? are they made of of the same stuff as iPods?

No, they are made of the same stuff that inkjet printer ink is made from.

Yes, really.

Don't Touch My Nano Tubes (0)

Nom du Keyboard (633989) | more than 8 years ago | (#15527720)

No you can't have my nano tubes. I need them for my new battery-capacitor. [slashdot.org]

Small pore, more flow ? (5, Interesting)

karvind (833059) | more than 8 years ago | (#15527749)

Does anyone have any idea why the small pores have higher flow rate through them ? My classical fluid dynamics class beats me here. Should be something to do with quantum effects at that scale, but can't guess it. Quantization in electronic states makes sense to me, but don't know what it is doing to 'flow dynamics'.


Cool work nevertheless. I wish they could do something with silicon nanowires as silicon is the second most abundant element on earth.

Re:Small pore, more flow ? (2, Interesting)

w33t (978574) | more than 8 years ago | (#15527807)

perhaps it has something to do with nanotubes being akin to (or perhaps actual) metamaterials. In that case it would seem that they posses some electromagnetic properties that greatly alter their interaction with certain materials.

Perhaps this increased flow is an indication that nanotubes are also very resitant to atmospheric wear (which would be a boon to using them for large-scale structures). Or perhaps it's an indication that they wear down at an accelerated pace.

All I know is that it is so awesome that these little macro-molecules (nice oxymoron there) keep surprising us with their strange and unusual properties. it's the strange and unusual that I so love about science in general.

Re:Small pore, more flow ? (2, Interesting)

955301 (209856) | more than 8 years ago | (#15527840)

capillary action. I'm guessing since they didn't declare it that they are good researchers - don't say it's so until you know it's so.

Water is an incredible molecule. It's affinity for weak bonding at boundary layers is legendary and might prove to be what is occurring here as well. Think about the edge of the water in your glass - it curves upward. You get the two edges together and it races up the glass.

That's my hypothesis anyway.

Re:Small pore, more flow ? (5, Informative)

kebes (861706) | more than 8 years ago | (#15527865)

I'm reading the original Science article now (sorry, only available to subscribers, although the Science summary [sciencemag.org] may be available to the general public).

The reason that the gas and liquid transport through nanotubes is so much higher than you might expect is due to the smoothness of the inside walls. The classic hydrodynamic equations have some amount of surface roughness inherently built into them. If you just naively scale them down to nano-dimensions, you'll predict very high resistance to fluid flow. However carbon nanotubes have "perfect" inside walls, that are atomically flat. This allows the water molecules (or gas, or whatever travelling inside them) to travel without "getting caught" or "bumping" into defects. In essence the atomic smoothness of the walls brings us into a whole new (nano) hydrodynamic regime.

This effect was predicted by computer simulations previously, but now has been actually observed in real samples. Very impressive.

Re:Small pore, more flow ? (1)

Spy der Mann (805235) | more than 8 years ago | (#15527876)

Does anyone have any idea why the small pores have higher flow rate through them ?

Laminar flow + less friction is a possibility.

Re:Small pore, more flow ? (1)

LiquidCoooled (634315) | more than 8 years ago | (#15527893)

Wouldn't the same principles behind capillary action explain this?

Re:Small pore, more flow ? (0)

Anonymous Coward | more than 8 years ago | (#15527897)

I sorta thought that "quantum" effects operate at subatomic scales; if you are talking about water molecules, you are operating at a much larger level.

Re:Small pore, more flow ? (0)

Anonymous Coward | more than 8 years ago | (#15527991)

Quantum dots are not sub-atomic, they are nanometer sized - carbon nanotube diameter is also few nanometers.

could be important for a hydrogen economy (2, Interesting)

tddoog (900095) | more than 8 years ago | (#15527753)

This could help in purifying water that will be separated into hydrogen for use in fuel cells etc. A reduction in purification costs is one step closer. I know, I know, there are lots of other challenges, but its a baby step.

Where are these US water shortages? Broadband in the US may suck but I wasn't aware of any water rationing.

Also, this micro fluid dynamics intrigues me. Increased flow rate at reduced diameters. Very cool. Sounds like a possible research field for the old PhD.

Re:could be important for a hydrogen economy (1)

Feyr (449684) | more than 8 years ago | (#15527778)

north carolina for most of last year if i recall correctly (i dont live there, just what a friend told me)

Re:could be important for a hydrogen economy (2, Interesting)

Numbah One (821914) | more than 8 years ago | (#15527847)

i do live in north carolina. we were 6" or more below normal for rainfall for the year. if it wasn't for end of year wetness, it would have been more. local governments restricted lawn watering, car washing, and some industrial applications in an effort to conserve. a lot of the creeks and rivers were at their lowest point in years.

interestingly, parts of florida are very dry right now. they've been having wildfires and have had to shut down i-95 more than once due to smoke and other hazards. some were hoping alberto would pass over the dry areas and help out the situation.

Re:could be important for a hydrogen economy (1)

Ana10g (966013) | more than 8 years ago | (#15527788)

Actually, not rationing, but restrictions do exist out west. Like Denver, CO, and the surrounding suburbs, (specifically Centennial), are still on water restrictions from a drought we had about 4 years ago, and I don't think they're going to repeal them. I suppose that's the price of living in a near-desert though. That, and there's not too many oceans around Denver (yet!).

Re:could be important for a hydrogen economy (0)

Anonymous Coward | more than 8 years ago | (#15528149)

Denver has an ample water supply from mountain water (ice/snow melt). Unfortunealty, much of this water is diverted to Arizona. Oddly enough, Arizona does not have watering restrictions.

Re:could be important for a hydrogen economy (0)

Anonymous Coward | more than 8 years ago | (#15527839)

America, especially the Midwest and Southwest, are a lot dryer than many people are aware. Many of these areas are desert or near desert, and municipal water supply is always a major issue. For the most part, much of the Southwest and parts of the Midwest are fed by huge irrigation systems that keeps the area's agricultural and pretty home landscaping watered. Huge rivers have been turned into small streams by water demand, and that demand is going to continue to grow as the population in these areas increases.

Whenever there is a large drought in any of these areas, it is not at all uncommon for outdoor watering of non-agricultural landscaping to be disallowed. I guess this could be construed as water rationing.

Re:could be important for a hydrogen economy (3, Insightful)

Surt (22457) | more than 8 years ago | (#15527861)

Out of curiosity, why would it be important to purify the water before separation into hydrogen/oxygen? Most of the methods I'm familiar with don't particularly care if the water is pure, the waste rate from impurities is meaningless, and cleaning just means occasional sludge removal.

Re:could be important for a hydrogen economy (1)

DAldredge (2353) | more than 8 years ago | (#15527926)

Dallas / Fort Worth and surrounding areas.

Re:could be important for a hydrogen economy (1)

ENOENT (25325) | more than 8 years ago | (#15528180)

I know, I know, there are lots of other challenges, but its a baby step.


Yup. Now the only major hurdle is the fact that hydrogen production is endothermic.


Re:could be important for a hydrogen economy (1)

tddoog (900095) | more than 8 years ago | (#15528344)

Yeah so is creating a voltage but that hasn't stopped people from using electricity.

Re:could be important for a hydrogen economy (0)

Anonymous Coward | more than 8 years ago | (#15528201)

Phoenix and Tucson

Materials science must be the top-level science (3, Insightful)

w33t (978574) | more than 8 years ago | (#15527754)

I've heard it said that materials science is the slowest science - and it's almost certainly true. It is taking forever to get consumer products from carbon nanotubes (with a few exceptions [blogs.com] ).

But all the uses found for a new material and all the new applications discovered - in many respects it certaily seems to be the most fruitful science (at least in the engineering and day-to-day sense).

Re:Materials science must be the top-level science (1)

xenocide2 (231786) | more than 8 years ago | (#15527810)

Forgive me for my ignorance, but how much do normal bike frames weigh?

Re:Materials science must be the top-level science (3, Funny)

numbsafari (139135) | more than 8 years ago | (#15527863)

They weigh about as much as the tangent bike frames.

Re:Materials science must be the top-level science (1)

w33t (978574) | more than 8 years ago | (#15527912)

There are frames that weigh less than that frame - but it's made from freakin nanotubes!

The bike is made of nanotubes kind of the same way you can make a pile of legos. The legos aren't being used as they should or could, but the pile is made of legos nonetheless.

Re:Materials science must be the top-level science (1)

BigCheese (47608) | more than 8 years ago | (#15527984)

Materials science is one of the most important fields of study there is.

If this new type of filter works it will mean major changes all over the world.

That's what's cool about material science. It may be slow but it can create all sorts of disruptive technology.

The Singularity really is near... (1)

slowness (576562) | more than 8 years ago | (#15527757)

We are at the "knee" of the evolutionary exponential curve. Everybody, hold your breath for another ten years, then take a deep breath and hold on tight. As tight as you can... Slowness

Re:The Singularity really is near... (1, Funny)

Anonymous Coward | more than 8 years ago | (#15527828)

Everybody trying to hold their breath for ten years would be an excellent way for us to prove evolution's "natural selection" theory..

Finally! (2, Funny)

bombadier_beetle (871107) | more than 8 years ago | (#15527761)

I was wondering how I was going to get all that salt out of my iPod.

Re:Finally! (1)

McBainLives (683602) | more than 8 years ago | (#15527925)

No! You're not seeing the full potential- we take all of the filtered-out salt and use it to make crystallized salt cases for the nano and shuffle models! It absorbs moisture, it's transparent, and all of those people who take their iPods jogging can use it as an emergency salt lick!

Quick! To the patent office!

Re:Finally! (2, Funny)

nickheart (557603) | more than 8 years ago | (#15528045)

mod up parent... he posted my joke first!

Good stop-gap solution... (1)

demongeek (977698) | more than 8 years ago | (#15527763)

...but wouldn't finding a way to lower water consumption (at least in first-world nations where I know places just throw water [excuse the pun] down the toilet) be a better measure. Sure, this can certainly help places (like the mid-western states) where water is very scarce, but maybe we ought to look at the source of the problem?

Re:Good stop-gap solution... (1)

drinkypoo (153816) | more than 8 years ago | (#15527812)

Sure, this can certainly help places (like the mid-western states) where water is very scarce, but maybe we ought to look at the source of the problem?

Yes. We should. We should do both in parallel. We are doing so. Therefore your comment is utterly useless. Thank you, please drive through.

Re:Good stop-gap solution... (1)

Zerbs (898056) | more than 8 years ago | (#15527823)

this can certainly help places (like the mid-western states) That's probably the worst place to use this technology, the mid-west is the farthest point from all the salt water the U.S. borders. Makes more sense in the southwest states.

Flushing toilet==Fixing a drink for LA (1)

HornWumpus (783565) | more than 8 years ago | (#15527934)

Sewage treatment requires lots of water in the mix. If there is'nt enough they have to add some at the treatment plant.

BTW once treated the water is often put back into the river.

Which is why I refer to flushing the toilet as 'Fixing a drink for LA and SF' (I live in Sacto).

nano (2, Funny)

uberjoe (726765) | more than 8 years ago | (#15527772)

When I first read the headline I was wondering how iPods got salty in the first place.

Re:nano (1)

bsartist (550317) | more than 8 years ago | (#15527821)

Easy: Lickable interface.

Re:nano (1)

BigCheese (47608) | more than 8 years ago | (#15527836)

Same here. You beat me to the post.

Desalinization vs Condensation? (1)

955301 (209856) | more than 8 years ago | (#15527774)


I wonder how it compares to Condensation?

The way that isn't mentioned in the article is to use a warm climate, moderately warm salt water, and relatively cold salt water to get the warmer water to condense from the air into a collection well. A half filled tank of warm water with cold water lines running over the water reservior will cause fresh water to condense on the lines, where it can then be collected.

If you compare this to the initial costs of replacing nano-tube filters, I bet it is competitive, if not better.

Re:Desalinization vs Condensation? (1, Informative)

Anonymous Coward | more than 8 years ago | (#15527820)

What you describe is nearly like the Seawater Greenhouse [seawatergreenhouse.com] , but it gives you added benefits of great growing environment for vegetables as well as the water produced.

Re:Desalinization vs Condensation? (2, Insightful)

BigCheese (47608) | more than 8 years ago | (#15528016)

This new method should only require pumps. From your description of condensation it requires temprature differentials. That will require power input as well as the pumps.

It may be more efficient (and cheaper) by simply being, well, simpler.

Re:Desalinization vs Condensation? (1)

bobs666 (146801) | more than 8 years ago | (#15528097)

Reverse osmosis is much cheaper then then boiling water.

Full Article (Slashdotted) (2, Informative)

Jack Zombie (637548) | more than 8 years ago | (#15527793)

Cheap Drinking Water from the Ocean

Carbon nanotube-based membranes will dramatically cut the cost of desalination.

A water desalination system using carbon nanotube-based membranes could significantly reduce the cost of purifying water from the ocean. The technology could potentially provide a solution to water shortages both in the United States, where populations are expected to soar in areas with few freshwater sources, and worldwide, where a lack of clean water is a major cause of disease.

The new membranes, developed by researchers at Lawrence Livermore National Laboratory (LLNL), could reduce the cost of desalination by 75 percent, compared to reverse osmosis methods used today, the researchers say. The membranes, which sort molecules by size and with electrostatic forces, could also separate various gases, perhaps leading to economical ways to capture carbon dioxide emitted from power plants, to prevent it from entering the atmosphere.

The carbon nanotubes used by the researchers are sheets of carbon atoms rolled so tightly that only seven water molecules can fit across their diameter. Their small size makes them good candidates for separating molecules. And, despite their diminutive dimensions, these nanopores allow water to flow at the same rate as pores considerably larger, reducing the amount of pressure needed to force water through, and potentially saving energy and costs compared to reverse osmosis using conventional membranes.

Indeed, the LLNL team measures water flow rates up to 10,000 times faster than would be predicted by classical equations, which suggest that flow rates through a pore will slow to a crawl as the diameter drops. "It's something that is quite counter-intuitive," says LLNL chemical engineer Jason Holt, whose findings appeared in the 19 May issue of Science. "As you shrink the pore size, there is a huge enhancement in flow rate."

The surprising results might be due to the smooth interior of the nanotubes, or to physics at this small scale -- more research is needed to understand the mechanisms involved. "In some physical systems the underlying assumptions are not valid at these smaller length scales," says Rod Ruoff, a physical chemist and professor of mechanical engineering at Northwestern University (who was not involved with the work).

To make the membranes, the researchers started with a silicon wafer about the size of a quarter, coated with a metal nanoparticle catalyst for growing carbon nanotubes. Holt says the small particles allow the nanotubes to grow "like blades of grass -- vertically aligned and closely packed." Once grown, the gaps between the nanotubes are filled with a ceramic material, silicon nitride, which provides stability and helps the membrane adhere to the underlying silicon wafer. The field of nanotubes functions as an array of pores, allowing water and certain gases through, while keeping larger molecules and clusters of molecules at bay.

Holt estimates that these membranes could be brought to market within the next five to ten years. "The challenge is to scale up so we can produce usable amounts of these membrane materials for desalination, or gas separation, the other high-impact application for these membranes," he says, adding that the fabrication process is "inherently scalable."

Eventually, the membranes could be adapted for a variety of applications, ranging from pharmaceuticals to the food industry, where they could be used to separate sugars, for example, says co-author Olgica Bakajin, a physicist at LLNL. "Practically, the next step is figuring out how to take a general concept and modify it to a specific application," Bakajin says.

"There are many studies that one can imagine to build upon this study," says Northwestern's Ruoff. "Our understanding of molecular processes will be helped by experiments of this type. There are interesting possibilities for nanofluidic applications, such as in nanoelectromechanical systems and in 'smart' switching [on and off] of the flow through such small channels."

Amount of Waste Water? (2, Interesting)

smannell (157236) | more than 8 years ago | (#15527801)

The article doesn't say how much waste water would be needed to de-salinize a given volume of H20, but if the water flows through with considerably less force than a traditional RO unit maybe there will be less waste water. This could be more important than the energy savings. A good comercial RO filter produces roughly 1 gallon of waste water for every gallon of potable water, and most home units produce two or more.

Energy (2, Informative)

Lord Satri (609291) | more than 8 years ago | (#15527806)

The challenge is not about methods to desalinize (there's plenty of methods [wikipedia.org] ), it's about finding a method which requires very little energy (and thus money) that it becomes advantageous to proceed to desalinization in the first place...

Orchid fractals (5, Interesting)

LiquidCoooled (634315) | more than 8 years ago | (#15527816)

I once read something about a class of fractals called >orchids [crowddynamics.com] .
They are the result of monitoring crowd flow dynamics and producing the formulas.

They too noticed that for a large crowd (concert, football match) crowd flow speed INCREASES with a number of small gates rather than one large gate, hence one by one through the turnstyles actually makes the process quicker.

This appears to be a similar unintuitive process.

Anyway, I know it wasn't totally on topic I just thought I would share.

Re:Orchid fractals (1)

gbjbaanb (229885) | more than 8 years ago | (#15528138)

Similarly for heavy traffic - if you reduce the speed limit during peak traffic times, the ovrall flow of traffic is greater. I guess its because of less wave effects, where you end up stopping and starting all the time.

a lot of things are un-intuitive, but correct.

And as a side effect... (2, Interesting)

ZSpade (812879) | more than 8 years ago | (#15527831)

I wonder if it will also sterilize any water passed through it, as carbon nano tubes seem to evoke cell death upon contact. This is one area where that could actually prove to be a benefit rather than a set-back.

Just being able to desalinize water cheaply is a pretty damn big breakthrough though, I know Los Angeles could use it with all the draughts they have. I mean how ironic is it that they'll have a 7 year drought and water shortages, and yet be right on the coast of the largest body of water in the world?

Re:And as a side effect... (1)

Abcd1234 (188840) | more than 8 years ago | (#15528103)

Well, given that the article claims pore widths allowing only seven water molecules to pass through at a time, one can probably conclude that it would also serve to sterilize (since most pathogens in the water would almost certainly be bigger than that).

Initial toxicity test refuted. (3, Informative)

Derek Pomery (2028) | more than 8 years ago | (#15528193)

Recent analysis of the test used,the methylthiazol tetrazolium (MTT) test shows that the test may have been screwed up by the fact that the MTT was binding to the nanotubes. Using a different toxicity test, NO toxicity was found.
Based on this, carbon nanotubes should probably be considered cleared of causing cell death for now.
Inconvenient for your filter, but a boon for many many other applications.

drinking nanotubes (1)

twy (803095) | more than 8 years ago | (#15528314)

If nanotube particles break out of the filter, they will end up in the filtered water! I wonder what the health risks are of drinking nanotubes. But for all I know, the environment is already full of nanoparticles produced naturally - or not?

Where? (0)

Anonymous Coward | more than 8 years ago | (#15527888)

There is no "Lawrence Livermore National Laboratory". There are the Lawrence Berkeley National Laboratory (formerly the Lawrence National Laboratory (LBL)), which is in Berkeley, and the Livermore National Laboratory, which is in Livermore. The whole reason LBL changed its name to Berkeley National Laboratory was so people wouldn't confuse it with the Livermore lab. Guess it didn't work.

Re:Where? (1, Informative)

Dahan (130247) | more than 8 years ago | (#15528066)

o rly? [llnl.gov]

Percentage salt remaining? (1, Insightful)

M0b1u5 (569472) | more than 8 years ago | (#15527950)

This is all well and good, but does the process increase the efficacy of removing the chlorides in sea water? This because 99.999% is not good enough: if you spray that on your farm - in a few years the evaporating water has left the remaining salts (Chlorides) behind and will have sterilised the soil so that nothing can grow in it.

This would be a major concern in areas where desertification is already rampant.

I have no idea what the accepatble level is, but it needs to be damn low before you can irrigate with desalinised sea water.

clueless (1)

RelliK (4466) | more than 8 years ago | (#15528020)

huh? your fresh water contains waaay more than 0.001% salt (as well as other minerals)

Re:Percentage salt remaining? (1)

fred fleenblat (463628) | more than 8 years ago | (#15528251)

if nothing else, the use of desalinated water for municipal supplies makes more "regular" water available for farming.

Very important topic (2, Insightful)

johansalk (818687) | more than 8 years ago | (#15528036)

Just as current wars are fought over oil, wide predictions are that future ones will be fought over access to water resources.

I like the other method... (4, Interesting)

PatTheGreat (956344) | more than 8 years ago | (#15528048)

This article raises two thoughts in my wonderful little head.

1) Why do they bother calling it "reverse osmosis?" From a quick review of high school biology, I have come to realize "reverse osmosis" really means "pumping through a filter."

2) I saw this other method in Discover that I really liked. Basically, it proposes using deep water and methane to flash-freeze water. All you need to do is to pump methane into water of the right depth, and it instantly freezes into that flammable ice mining rigs love to dig up and play with, without like, refrigerating it. Anyways, as it freezes, all the salt gets pushed out and it floats to the top, so all you have to do is melt the ice and reuse the methane. It appealed to the recycler in me, and it seems to me some tubes and plumbing would be easier than nanotubes, eh?

New use for iPods... (0)

Anonymous Coward | more than 8 years ago | (#15528057)

From the headline I thought we were going to be able to desalinate water with our iPod nanos!

But but but... (1)

Ancient_Hacker (751168) | more than 8 years ago | (#15528114)

If these doohickeys have pores that are so small, how prone are they to clogging? Lots of things work just fine in the clean laboratory but dang it, just don't work in the real world, where there is rumored to be dust. It sounds like these things could get clogged by anything bigger than a few water molecules, which includes an awful lot of things out there.

Nano? (1)

christopherfinke (608750) | more than 8 years ago | (#15528150)

I don't think nano [nano-editor.org] needs to be desalinized; it's pretty good the way it is. It could use syntax highlighting though...

arctic salt (1)

DarthTaco (687646) | more than 8 years ago | (#15528184)

Awesome! Now we can replace the polar ice caps with polar salt caps!

It can trap green house gasses? (1)

ScottLindner (954299) | more than 8 years ago | (#15528213)

If it can trap green house gasses too, I'd love to have a pair of underwear made of this stuff so I can fart all day long and not bother anyone.

Water + salt through filter clogs system? (3, Interesting)

owlstead (636356) | more than 8 years ago | (#15528241)

What I never understand with these kind of filters is where the waste ends up. There is quite a lot of salt in the water, so these filters should clog pretty quickly, and just rinsing them every minute does not seem to be very practical. Does anyone know how this works?

Huge breakthrough (1)

wrcromagnum (902396) | more than 8 years ago | (#15528261)

This could be one of the most important discoveries in history. Most of the world right now is facing water shortages. In some areas, such as the Middle East, nations fight wars over water. If we could actually implement techonology to make the world's oceans drinkable just think of the problems we would solve. Right now around 70% of Africa does not have access to clean water. The Sahara is expanding because African nations are trying to do too much with too little water and the soil is blowing away. Just imagining the possibilities of this technology is giving me tingles. I just hope that the companies that use this try to deliver at the cheapest possible cost.

Can somebody explain to me please... (1)

1800maxim (702377) | more than 8 years ago | (#15528320)

How Apple is tied to all of this? I read the summary, i read the article, and perhaps it's due to cryptographic nature of those reporters, but I can't figure out what Steve Jobs' thinks of this...
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