New Nano Desalinization Method

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."

Comments

End Our Wet Drought!

[aslate]

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...

Small pore, more flow ?

[karvind]

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 ?

[w33t]

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 ?

[955301]

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 ?

[Firehed]

So what happens when they get all clogged up with the salt?

could be important for a hydrogen economy

[tddoog]

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

[Numbah One]

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.

Amount of Waste Water?

[smannell]

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.

Orchid fractals

[LiquidCoooled]

I once read something about a class of fractals called >orchids.
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.

And as a side effect...

[ZSpade]

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?

Huge boon to hydrogen economy?

[RingDev]

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

I like the other method...

[PatTheGreat]

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?

Water + salt through filter clogs system?

[owlstead]

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?

Or huge boon to Uranium enrichment...

[maillemaker]

My first thought was much more sinister.

Steve