backtop


Print 74 comment(s) - last by 16nm.. on Jul 24 at 11:12 PM

New membrane will help to ensure many parts of the world have easy access to drinking water.

One of the biggest, but least appreciated problems facing many regions of the world is lack of clean drinking water, a common problem in impoverished nations.  Ironically, many of these nations rest beside large bodies of salt water. Ttypically, processing salt water into fresh water is expensive and requires large dedicated plants.

DailyTech previously chronicled how wind-power driven desalinization plants which used membranes were being developed.  Now another major breakthrough in the field has been devised, this time concerning the membranes.

Researchers from several international universities have developed a chlorine-tolerant membrane which turns salt water into clean drinking water.  Typically, salt water is treated with chlorine to remove bacteria and microorganisms that would grow and form a biofilm on the membrane, blocking it.  However, chlorine destroys past membranes which were build using amide-polymers (nitrogen based).  This meant that that the water had to be dechlorinated before being sent to the membrane, a relatively expensive and complex process.

The new membrane is formed from sulfonated copolymers.  It took researchers Professor Benny Freeman with the The University of Texas at Austin, James E. McGrath of Virginia Tech University, and Ho Bum Park of the University of Ulsan in South Korea three years to develop the membrane for which they have filed a patent.  The new membrane is resistant to chlorine allowing the elimination of dechlorination.

Says Professor Freeman, "If we make the desalination process more efficient with better membranes, it will be less expensive to desalinate a gallon of water, which will expand the availability of clean water around the world.  It promises to eliminate de-chlorination steps that are required currently to protect membranes from attack by chlorine in water.  We believe that even a small increase in efficiency should result in large cost savings."

Researchers also believe the design will help reduce carbon dioxide emissions in developing nations by decreasing the electrical needs of the generation process. 

Professor Freeman explains:

Energy and water are inherently connected.  You need water to generate power (cooling water for electric power generation stations) and generation of pure water requires energy to separate the salt from the water. That energy is often generated from the burning of fossil fuels, which leads inevitably to the generation of carbon dioxide. Therefore, if one can make desalination more energy-efficient by developing better membranes, such as those that we are working on, one could reduce the carbon footprint required to produce pure water.

It was a combination of luck and hard work that brought the researchers upon the novel suflonated class of membranes.  This class of materials enjoys a high tolerance to aqueous chlorine, making it surprisingly a far better fit than membrane materials currently in use.

Professor Freeman, who holds the Kenneth A. Kobe Professorship in Chemical Engineering and the Paul D. & Betty Robertson Meek & American Petrofina Foundation Centennial Professorship in Chemical Engineering, states, "Basically, Dr. McGrath radically changed the chemical composition of the membranes, relative to what is used commercially, and the new membranes do not have chemical linkages in them that are sensitive to attack by chlorine."

The research was funded by the Office of Naval Research and the National Science Foundation-Partnerships for Innovation Program. 

The findings will be reported in a paper in this month's edition of the German Chemical Society's journal, Angewandte Chemie, with Mehmet Sankir and Zhong-Bio Zhang, both of Virginia Tech, as additional coauthors.



Comments     Threshold


This article is over a month old, voting and posting comments is disabled

Swank.
By Motoman on 7/23/2008 11:41:15 AM , Rating: 5
Good to see progress in this area. If we think water shortages are bad now...say, mostly in developing and/or highly-stressed countries, we are in for another think in the near future. Everybody is going to be facing massive water shortages...including the US. Considering the state of affairs in places like Phoenix and Las Vegas just for starters, it might be time to be thinking about putting up some de-salination plants in key areas on the US coastlines too.

Bonus item: real sea-salt to boost the margarita industry!




RE: Swank.
By FITCamaro on 7/23/2008 12:19:36 PM , Rating: 2
Margaritas.....*drools*.....a food group in my family.


RE: Swank.
By eye smite on 7/23/2008 12:21:21 PM , Rating: 2
It's always good to be forward thinking on things. How about something more practical for water catchments like man made lakes and resevoirs which has been being done all along? :-)


RE: Swank.
By Ringold on 7/23/2008 12:50:32 PM , Rating: 2
Florida's played that game, and only managed to destroy most of the Everglades in the process.

A water management district, which ever one it is over by Daytona, did a study to consider its options moving forward, and the winner for cost-effectiveness was a desalination plant.

Georgia may need it as well. They've got your man made lake, Lake Lanier, and they didn't spare them a near-crisis last year.


RE: Swank.
By mmatis on 7/23/2008 2:00:43 PM , Rating: 3
The St. Johns River Water Management District is a bunch of lying maggots that are out to build their empire. They suck up to whoever suits them, and screw the rest. Viera is a case in point. Cow pasture that was a major recharge area for the St. Johns River. Good ol' SJRWMD lets the owners build a whole new city without ANY wetlands mitigation, even though the friggin' cows were standing belly-deep in water every summer. Now they're trying to screw Jacksonville by letting Orlando suck out water.

Managed to destroy most of the Everglades? Yeah, right! The South Florida Water Management District scum has caused more of that than anyone else. The stench of evil is overwhelming, and the filthy maggot pigs won't do a thing to stop them!


RE: Swank.
By masher2 (blog) on 7/23/2008 7:01:42 PM , Rating: 5
> "Georgia may need it as well. They've got your man made lake, Lake Lanier, and they didn't spare them a near-crisis last year. "

The "near crisis" is because the Army Corp of Engineers is required to release 3.2 billion gallons a day from Lake Lanier -- every day, crisis or not -- to help protect endangered species downstream.

They also accidently released some 23 billion gallons extra over a two month period, due to faulty gauge, but the Atlanta water crisis was purely a manmade incident.

As for Florida's Everglades, before man began tinkering with the ecosystem there, South Florida was a malarial swamp, wholly unfit for human habitation. Most people consider malaria a tropical disease, but in the 1800s, it was a widespread, wholly "American" disease...eventually stamped out due to our efforts to control the environment.


RE: Swank.
By Ringold on 7/23/2008 9:37:57 PM , Rating: 2
I was aware of what was wrong with Lanier, but if they're going to keep pumping the water to keep the environmentalists happy (there's also some minimum flow needed for some power plants here in FL if I recall) then that will ultimately have to come from somewhere. The long-lasting drought doesn't help, either. They, like we here in Florida, face a potential looming water shortage regardless of cause, I was just defending desalination, which could (at a cost) make water shortages history.

That all may be true of the Everglades, and I'm not GreenPeace type, but if we consider it to be a special habitat worthy of conservation it would've been cheaper, perhaps, to not have wrecked it initially and planned growth a bit better rather than now be paying billions out the nose to pseudo-restore it. Billions of taxpayer dollars, no less.

I also know some conservative folk that have lived and gone fishing and hunting around in Central Florida long enough to see the damage done to the lake system around here, such as lakes that one could previously see to the bottom now resembling pea soup. Lake Apopka was a giant septic tank until only the last few years -- and it smelled like it any time I flew overhead, several thousand feet up. Could also often see a sort of oily film across its entire surface, but that was many years back now. I can point my finger at needless environmental damage without being a flaming liberal. ;)


RE: Swank.
By Ammohunt on 7/23/2008 2:20:37 PM , Rating: 2
Problem with that is it makes sense!. The water shortages we have here in colorado are mainly due to the eco-freaks not allow resevoirs to be built not to mention 95% of the water collected is used for farming.


RE: Swank.
By andrinoaa on 7/23/08, Rating: -1
RE: Swank.
By masher2 (blog) on 7/23/2008 7:27:38 PM , Rating: 4
> "but those pesky environmentalists keep pointing out the fact that the whole of the continent can be turned into a dam, but if it doesn't rain, its all for naught."

Cute, but the fact remains that every single day, tens of billions of gallons of fresh water flow out of Australian rivers into the sea. All wasted...because no dam existed to hold it. As a continent, Australia receives much more water in rainfall than it needs.

Oh and those dams generate massive amounts of electrical power also.

> "Do you have a problem with this , glowboys? "

None whatsoever, besides the fact that desalination is still many dozens of times more expensive than simply building more dam capacity.


RE: Swank.
By goz314 on 7/23/2008 9:36:55 PM , Rating: 1
quote:
As a continent, Australia receives much more water in rainfall than it needs.


Oh... really? I would like to see you waste your time trying to actually qualify that statement.


RE: Swank.
By Ringold on 7/23/2008 9:44:45 PM , Rating: 2
Well, I wasted roughly 3 minutes opening up Google Earth, zooming in to Australia, and locating several rivers that appeared to be doing what rivers do and what masher said -- dumping lots of fresh water in to the ocean.


RE: Swank.
By croc on 7/23/2008 9:38:02 PM , Rating: 1
And I am sure that you have the links to back up this mis-informed opinion?

The Murray-Darling river basin is now having problems delivering enough water to South Australia as it is. (and it doesn't reach the ocean...)

West Australia has pretty much used up all of their bore water, and are building several de-sal plants.

New South Wales will be building a de-sal plant, possibly...

I am sure that with all of your environmental science degrees, the CSIRO would hire you in a snap.


RE: Swank.
By masher2 (blog) on 7/23/2008 10:00:16 PM , Rating: 3
> "And I am sure that you have the links to back up this mis-informed opinion?"

Always. The mean rainfall of Australia is ~500mm. That works out to an annual volume of 3,843,425,000,000 cubic meters of water. Converting to gallons, thats 1,015 trillion gallons falling on the continent each year:

http://www.bom.gov.au/climate/change/rain.shtml

Per capita water consumption for Australia is 115 kL (30,000 gallons):

http://www.environment.gov.au/soe/2006/publication...

With 20.4 million people in Australia, that means total rainfall is actually 1700 TIMES as much water as you actually need....even assuming not a single drop is ever used more than once (no grey-water recycling, etc)

Most water is wasted. Thanks for playing.


RE: Swank.
By croc on 7/24/08, Rating: 0
RE: Swank.
By masher2 (blog) on 7/24/2008 9:03:25 AM , Rating: 2
> "Note that most of all that '500mm' average you quote comes from the northern coastal fringes. "

The average rainfall in the Sydney basin is 1200 mm -- over twice the average for the entire continent. The average rainfall in Perth is 870 mm -- 50% more the the continental mean. Adelaide's rainfall: 629 mm. Melbourne's rainfall: 800mm.

Yes, more rain falls in the tropical North. But when over 1700 times as much rain falls as you actually need, even the rainfall in the south is sufficient -- were it all to be properly used.

Take a look at any Australian river flowing into the sea. That's fresh water-- all wasted. The Fitzroy river alone has been measured at flow rates up to 640 billion gallons per *day*. The Murray river -- easily available in the south -- discharges some 17 billion gallons a day. Again, all wasted.

As for the "protected rainforest, wetlands, etc" -- that's simply more proof this is a problem of desire and initiative, rather than substance. The north is too wet, and the south too dry. The solution to that problem should be obvious to anyone....transfer some water.


RE: Swank.
By andrinoaa on 7/24/2008 6:33:11 PM , Rating: 2
You obviously don't live here, mash. Its not what we have on the ground. Melbourne hasn't had decent rain for nearly two decades. We have lots of dams but they are running on empty. What is the point of having more?
Lies , damn lies and stastistics.
And besides, what arrogance you have. All water that flows to the sea is wasted!?!?!? Thats the kind of thinking that has destroyed half the environment in the fisrt place totally IGNORANT thinking. Its time you stopped defecating in your cereal bowl, mate.


RE: Swank.
By andrinoaa on 7/24/2008 6:44:32 PM , Rating: 2
The Murray river stopped flowing to the sea years ago. The mouth is now threatening to turn acidic PERMANENTLY. This will cause untold ecologoical damage to the area. Agriculture may need to be abandoned and south australia's water supplies are threatened too. Your rainfall figures look great but are not reflective of what we see.
Let me repeat. Damming the far north and piping water south is too expensive because of the distance so we need to find local initiatives. Now, next time you chosse to look up information in google, make sure its relevant. Not VAPOURWARE


RE: Swank.
By codeThug on 7/23/2008 10:38:21 PM , Rating: 2
...so quiet you could hear a kangaroo drop...


RE: Swank.
By andrinoaa on 7/24/2008 6:52:18 AM , Rating: 1
Nice try masher2, but it just goes to show statistics, lies and more damn lies.
Australia can be divided in two. The tropical north and the rest. Its true lots of rain falls in the tropics. But the rest of the country where the majority lives is now on borrowed water. Damming all this water would utterly destroy the barrier reef and most of the great fishing grounds off the coast. It is also inhospitable in the dry and unstoppable in the wet. Its like trying to harness a cyclone. The environment up north is finely tune to the seasons. Any large scale damming is going to be on a knife's edge.
In the past we built dams everywhere and that is a major reason why we are in a terrible state now - we didn't know what we were doing. We assumed the good times would keep rolling on forever.
Studies have been made to see if the water can be redirected and the figures come back as many times more expensive than desal.


RE: Swank.
By masher2 (blog) on 7/24/2008 8:49:02 AM , Rating: 2
> "Damming all this water would utterly destroy the barrier reef and most of the great fishing grounds off the coast."

Stuff and nonsense. First of all, you you don't need to dam anywhere near "all" this water, or even 1% of it. As I demonstrated, Australia receives nearly 2000 times as much water as it needs...you only need to dam a small part of it to solve your problems.


RE: Swank.
By andrinoaa on 7/24/2008 6:22:04 PM , Rating: 2
You seem to like to get to the tiniest of peices and pick holes but you don't get the big picture. Daming the water while technically possible, is beyond our country's financial capacity. It was already tried out west. It is called the Ord river dam. Its a total fiasco.It has lots of water but it is so far away from the population centres, it may as well be on the moon. This was the main point, the environment was a byproduct. But it seems you would be perfectly happy to defecate in your own cereal bowl. Small children do that.
You always seem to missunderstand the big picture, masher2.
My posting was about using WAVE power to run desal. The new membrane would be ideal!


RE: Swank.
By mmatis on 7/24/2008 9:27:27 PM , Rating: 1
Quelle surprise! Another left-wing butt-wipe spewing their lies. Why don't you go suck Osama like the rest of your media buddies are doing?


RE: Swank.
By andrinoaa on 7/24/2008 6:57:48 PM , Rating: 2
"besides the fact that desalination is still many dozens of times more expensive than simply building more dam capacity."

You devalue your cache when you exaggerate like this.
$1.5 billion for 300 megaliter desal plant. A new dam would have to be of this size to be warranted. We don't have any more rivers of any consequence in Victoria. How much does this cost? Nothing because its VAPOURWARE!!!!


RE: Swank.
By andrinoaa on 7/24/2008 7:00:48 PM , Rating: 2
Sorry , that should read 300 Gigaliters. ( in a hurry)


RE: Swank.
By andrinoaa on 7/24/2008 7:04:33 PM , Rating: 2
SORRY again, having a bad hair day.
the latest figures. $3.1 Billion for 150 billion litres per year plant


RE: Swank.
By mmatis on 7/24/2008 9:30:57 PM , Rating: 2
You aren't related to Goebbels, are you?


RE: Swank.
By andrinoaa on 7/24/2008 7:07:15 PM , Rating: 2
SORRY again, having a bad hair day.
the latest figures. $3.1 Billion for 150 billion litres per year plant
Its a pitty we cannot retract postings when we realise we stuffed up, lol.


RE: Swank.
By mmatis on 7/24/2008 9:28:59 PM , Rating: 2
And you have the guts to claim masher can't get his facts straight! Putrid stench of filthy maggot swill...


RE: Swank.
By Alexstarfire on 7/23/2008 4:57:14 PM , Rating: 2
Ummm, can't we use some plastic and the SUN to desa;inate water? I know that I got this info out of a TV show, but it really does seem to make logical sense.


RE: Swank.
By Solandri on 7/23/2008 5:11:01 PM , Rating: 2
That suffers from the same problem as solar power - it requires too much surface area and isn't fast enough. Heck, all the oceans undergo evaporation 50% of each day, with a large portion of the resulting fresh water falling onto land where it collects in lakes, rivers, and aquifers. And it's still not enough. A few desalination ponds aren't even a fraction of a drop in the bucket compared to all that. It may work for a small town or village by the ocean, but for any sizeable urban area it's not space-effective.


RE: Swank.
By rcc on 7/23/2008 5:50:21 PM , Rating: 1
Uh, 50% of the ocean's evaporate everyday? I think you better check that.


RE: Swank.
By ggordonliddy on 7/23/2008 6:13:47 PM , Rating: 1
Maybe he meant that they evaporated only during half of the day (12 hours average)?

Does evaporation occur when there is little or no sunlight?


RE: Swank.
By masher2 (blog) on 7/23/2008 7:19:16 PM , Rating: 3
> "Does evaporation occur when there is little or no sunlight? "

Sure. Put a shallow pan of water out on your porch overnight...in the morning it'll be gone (depending on your local relative humidity, of course)


RE: Swank.
By bdewong on 7/24/2008 2:22:58 PM , Rating: 2
I did, but the cats drank it all


RE: Swank.
By mles1551 on 7/23/2008 2:05:45 PM , Rating: 2
Don't forget about LA & San Diego.


RE: Swank.
By Seemonkeyscanfly on 7/23/2008 6:05:51 PM , Rating: 2
Why? Really anything worth saving out that way?? :P


RE: Swank.
By TomCorelis on 7/24/2008 1:20:07 AM , Rating: 2
Why does everyone have to hate on Southern California? That's my homeland you're talkin' bout, pal.


RE: Swank.
By iamezza7 on 7/24/2008 12:26:12 PM , Rating: 2
maybe because you can't take obvious jokes?


RE: Swank.
By theapparition on 7/24/2008 1:08:13 PM , Rating: 2
Your homeland is now a northen extension of Mexico.


RE: Swank.
By 16nm on 7/23/2008 3:38:04 PM , Rating: 1
quote:
Considering the state of affairs in places like Phoenix and Las Vegas just for starters, it might be time to be thinking about putting up some de-salination plants in key areas on the US coastlines too.


I guess conservation would be a stupid idea. It sure would be hard to imagine fewer golf courses and water fountains in desert regions like these.


RE: Swank.
By FITCamaro on 7/23/2008 4:23:34 PM , Rating: 2
It's always about giving up things to some people.


RE: Swank.
By andrinoaa on 7/23/2008 7:11:47 PM , Rating: 1
as I posted elseware. Surely a good sized meal is better for you than supersizing? What are you giving up by using a little sense and not burning eveything JUST BECAUSE you can? Its all part of living in a society. give a little , take a little. If its all take, no one ends up with anything. Didn't your papy teach you anything?


RE: Swank.
By masher2 (blog) on 7/23/2008 7:20:16 PM , Rating: 2
In the particular case quoted by the OP, you're giving up golf courses and water fountains.

Why give up anything at all -- if we don't have to?


RE: Swank.
By 16nm on 7/23/2008 10:12:20 PM , Rating: 1
Not giving up ALL golf courses and fountains but giving up some. I'm practical, not radical.


RE: Swank.
By masher2 (blog) on 7/24/2008 9:06:33 AM , Rating: 2
When its your own particular course on the chopping block, you might feel differently.

In any case, you didn't answer the question. Why give up anything, if you don't need to?


RE: Swank.
By 16nm on 7/24/2008 11:12:01 PM , Rating: 2
The OP was using the present tense as was I. If water is limited in these regions then conservation is wise. When water becomes plentiful then conservation will not be needed, right? It is a simple matter of adjusting to the situation at hand. It is like with gasoline. It is expensive and supposedly in short supply so we use less of it. We are conserving. I don't know why I had to spell it all out for you.

quote:
Why give up anything, if you don't need to?


There is a need to. If you've ever been to Lake Mead then you'd know this. Hopefully, this won't be the case when this new technology is available. We will just have to wait and see. Until then, conserve! The sooner you conserve then the less you have to.

http://www.reuters.com/article/domesticNews/idUSN1...


RE: Swank.
By Seemonkeyscanfly on 7/23/2008 6:17:27 PM , Rating: 2
I was going to say the desert is not exactly the best place to put a home.
It kind of reminds me of some third world country in Africa (first thing that comes to mind not picking on the countries of Africa) where 1,000's are starving. I keep thinking pick up your stuff and move to where the food is and stop waiting for it to come to you....I know not nice but there is some truth in the thought...you want food be near food, you want fresh water be near fresh water.

Though I must say it is a good thing to develop water plants like this....


RE: Swank.
By andrinoaa on 7/24/2008 7:08:43 AM , Rating: 2
Thats how the Israel/Palestine war came about. Some one assumed that the people who lived there didn't mind some one coming over and TAKING OVER!!
Have you seen the refugee camps in the news? Its because the local population doesn't want foreigners taking over.
Not as easy to implement as it seems.


"I'd be pissed too, but you didn't have to go all Minority Report on his ass!" -- Jon Stewart on police raiding Gizmodo editor Jason Chen's home

Related Articles













botimage
Copyright 2014 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki