Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
×
Earth Sci-Fi Science

Frank Herbert's Moisture Traps May Be a Reality 226

Omomyid writes "In the seminal science fiction book 'Dune,' Frank Herbert envisioned the Fremen collecting water from the air via moisture traps and dew collectors. Science Daily reprints a press release from the Fraunhofer Institute in Stuttgart, where scientists working with colleagues from Logos Innovationen have developed a closed-loop and self-sustaining method, no external power required, for teasing the humidity out of desert air and into potable water."
This discussion has been archived. No new comments can be posted.

Frank Herbert's Moisture Traps May Be a Reality

Comments Filter:
  • Still suits next? (Score:5, Insightful)

    by icebike ( 68054 ) on Tuesday June 09, 2009 @07:15PM (#28272971)

    If you extract moisture from already very dry are do you not create a dead zone down wind?

    There is life everywhere in the desert, most of which is tuned to live on very little water, but all of which need water from some source occasionally.

    Pushing humans into these areas where the only source of water is minimally moist seems rather pointless and ill advised.

    Would it work on mars?

    • Re:Still suits next? (Score:4, Interesting)

      by ShadowRangerRIT ( 1301549 ) on Tuesday June 09, 2009 @07:22PM (#28273039)
      Practically speaking, I doubt these traps could extract enough moisture from the air to have any effect on the humidity more than a few meters from the device. Even in huge numbers, the amount of air that comes in contact with one is negligible compared to the volume of air over the desert (the devices are on a roughly 2D plane, the atmosphere is 3D). Since the water would likely be used in the immediate vicinity (this doesn't look efficient enough to actually allow the export of water), whether it is used for crops or people, it will be added back into the local water cycle soon enough. At worst it will create minor, artificial oases. Remember, this air eventually passes over bodies of water which are more than capable of replenishing any moisture lost.
      • Re: (Score:3, Interesting)

        by Chyeld ( 713439 )

        Do you know why it's illegal to collect rainwater in a barrel in Utah and Colorado?

        If there is only a gallon of water in the air over an acre of land, removing a quart does in fact change the balance of things.

        • by Bester ( 27412 ) on Tuesday June 09, 2009 @07:59PM (#28273329)
          From a quick googling it seems that the reason that water tanks are illegal in the above states is not to do with affecting the local environment but more to do with the fact that it 'deprives' downstream users of their share.

          I get the feel from the articles that downstream providers are farmers and not parched wildlife.

          Charles
          • Not quite (Score:3, Informative)

            by WindBourne ( 631190 )
            It is not about downstream rights, but PRIOR rights. Big difference. Out here in the west, our saying is:
            Whiskey is for drinking, and water is for fighting.
            Sadly, it seems like Texans and Easterners want to come here and pollute our water (which we have precious little of).
            But all that MAY be changing. We, as individuals, have been prevented from capturing the runoff due to western water law. However, some lawyer and engineers have recently figured out that due to all concrete, farm lands, etc and our
        • Re:Still suits next? (Score:5, Informative)

          by compro01 ( 777531 ) on Tuesday June 09, 2009 @08:00PM (#28273345)

          I think you're off by a few orders of magnitude.

          According to http://www.nationalatlas.gov [nationalatlas.gov], the driest parts of Colorado get about 7" of rain annually (average rainfall is about 15"). that comes to 190,080 gallons per acre and would provide the total (drinking, washing, etc.) annual water usage (approximately 100 gallons per day per person, according to the US geological survey [usgs.gov]) of 5 people.

        • Re:Still suits next? (Score:5, Informative)

          by larry bagina ( 561269 ) on Tuesday June 09, 2009 @08:00PM (#28273347) Journal
          It's illegal because their water rights are based on a first come (excluding Indians) basis. Conventional wisdom (since disproven) was that collecting rainwater prevented it from going to it's rightful owners. More recent scientific studies have demonstrated that only 3% of rainwater ends up in the waterways.
        • Re: (Score:3, Insightful)

          It seems like if you are able to collect a quart of rainwater in a reasonably sized, "barrel", then there is a lot more than a gallon of water in the air over that acre.

        • by SuperBanana ( 662181 ) on Tuesday June 09, 2009 @08:22PM (#28273537)

          Do you know why it's illegal to collect rainwater in a barrel in Utah and Colorado? If there is only a gallon of water in the air over an acre of land, removing a quart does in fact change the balance of things.

          That's a load of pseudoscience, backing up a law that exists only for revenue, cronyism, and political control. If you store water off your roof or that falls from the sky, and then use it in your home or for irrigation, you're returning that water right back into the water table...in fact, use in the home returns it more effectively, because it is reintroduced a few feet under the soil by your septic system. You're not 'stealing' water- it doesn't go anywhere.

          If you want to know the real reason laws like that exist, read The Milagro Beanfield War [wikipedia.org] (annoyingly, that link is about the movie, not the book.) I read it in middle school, and it gave me great insight into how big business pushes citizens around.

          Also, you can take a look at what the Israelis are doing to all of the rivers that feed into or border Palestine for a great example of how water is controlled for racial oppression and political power.

        • by jandoedel ( 1149947 ) on Tuesday June 09, 2009 @08:22PM (#28273539)
          Only a gallon of water over an acre of land? I doubt it. I'm not really used to the Imperial System, but I'll try my best to do the calculation in it. 1 acre = "how much a man with an ox can manage in 1 day" 1 gallon = "1 eights of a bushel" 1 bushel = "the volume of a pile of wheat which weighs 64 tower pounds" 1 tower pound = "5400 troy grains" 1 troy grain = "64.79891 milligrams" 1 quart = "a quarter of a gallon" density of wheat = 950 000 karat / hogshead average humidity in Colorado = 40% assume a humidity of 40%, and you get about 40 gallons of water in the furlong of air over an acre of land. A quart doesn't really seem to make that much of a difference.
          • by jandoedel ( 1149947 ) on Tuesday June 09, 2009 @08:25PM (#28273567)

            (forgot the line breaks)

            Only a gallon of water over an acre of land? I doubt it.

            I'm not really used to the Imperial System, but I'll try my best to do the calculation in it.
            1 acre = "how much a man with an ox can manage in 1 day"
            1 gallon = "1 eights of a bushel"
            1 bushel = "the volume of a pile of wheat which weighs 64 tower pounds"
            1 tower pound = "5400 troy grains"
            1 troy grain = "64.79891 milligrams"
            1 quart = "a quarter of a gallon"
            density of wheat = 950 000 karat / hogshead
            average humidity in Colorado = 40%

            assume a humidity of 40%, and you get about 40 gallons of water in the furlong of air over an acre of land. A quart doesn't really seem to make that much of a difference.

        • by Idaho ( 12907 ) on Wednesday June 10, 2009 @04:55AM (#28276837)

          Do you know why it's illegal to collect rainwater in a barrel in Utah and Colorado?

          Because it is hard to tax the collection of rainwater?

          Maybe I'm too cynical but I just cannot honestly imagine that this has anything to do with any actual environmental concern.

    • Re: (Score:3, Interesting)

      by msobkow ( 48369 )

      I don't think they'll be down to the level of a still suit for quite a few years yet. Equipment like the urine/water recycling system on the space station or the article's desert "dehumidifier" are bulky.

      Plus we just don't have any real economic incentive for creating still suits -- we don't have a lot of people who want to live in the deep deserts.

      • Re:Still suits next? (Score:4, Informative)

        by Hatta ( 162192 ) on Tuesday June 09, 2009 @07:51PM (#28273291) Journal

        Last I checked, there were millions of people in Phoenix, Las Vegas, etc..

      • Actually, if the article's right and people could start using the Negev as a water source, I can think of several million people with a real economic incentive to use these things.

      • How about mining? I'm sure there is a lot of interesting stuff lying under the desert sands.

        There are plenty of reasons for people wanting to live in the desert. If only because the rest of the world is getting quite full.

      • All but the most barren deserts on this planet usually have a replenishing water supply somewhere. A pump, a cistern, and some plastic bottles is much easier to maintain (not to mention more comfortable) than a still suit will ever be.

    • It certainly would reduce the amount of humidity downwind. Luckily, downwind is where some poor bastard who isn't you lives. Handy, isn't it?

      (In a less "caricature of a Fremen libertarian" vein, I imagine that this sort of tech, on a large scale, could indeed have unpleasant effects for those downwind of it. Looking at the stark difference in climate of otherwise similar regions, one in front of the big mountain range that blocks moist air, and the other behind it, is pretty much geography 101 stuff, the
    • I don't think this will be used on a large enough scale to seriously affect the environment

      • Re: (Score:3, Insightful)

        by ls671 ( 1122017 )

        Hmm... I suspect that has been said about technologies that after a while ended up being used on a large enough scale to affect the environment.

        Note that I am not saying that this specific technology would end up being used on a large enough scale. I am just reminding history.

    • Forget the still suit, I'm trading my ticket for passage to Alderan for a used land speeder so I can become a moisture farmer!

      Now, if I could only find a droid who speaks the binary language of moisture evaporators...
  • by levicivita ( 1487751 ) on Tuesday June 09, 2009 @07:18PM (#28273009)
    How do they expect to keep such large structures safe from worms? I guess this is a typical melange bull market phenomenon. As soon as the price of spice jumps past $70 these people start building unsustainable castles in the sand. I for one will continue diligently keeping urinating into my stillsuit with the water recycling conservatively set on 'maximum.'

    Walk without rythm, fellow travelers.

  • When I was 12 they taught us how to make a moisture trap with a can and some cellophane. Granted we weren't in a desert, but I am surprised if this "new" development surprises anybody.
    • by gstoddart ( 321705 ) on Tuesday June 09, 2009 @07:57PM (#28273321) Homepage

      When I was 12 they taught us how to make a moisture trap with a can and some cellophane. Granted we weren't in a desert, but I am surprised if this "new" development surprises anybody.

      Clearly, this is on a larger scale and far more impressive than what you did when you were 12.

      Seriously, just because you did something which is conceptually similar, doesn't mean that this isn't an advance. Conceptually, flight hasn't changed since the Wright Brothers. Practically, it obviously has.

      Cheers

  • by scourfish ( 573542 ) <scourfish@@@yahoo...com> on Tuesday June 09, 2009 @07:25PM (#28273065)
    What I really need is a droid that understands the binary language of moisture vaporators.
    • Re: (Score:2, Funny)

      by Anonymous Coward

      It's amazing how many articles pass through this forum to which this is a perfectly appropriate response.

    • These are not the droids you are looking for.

      Move on.

  • by Chyeld ( 713439 ) <chyeld.gmail@com> on Tuesday June 09, 2009 @07:26PM (#28273069)

    Daily reprints a press release from the Fraunhofer Institute in Stuttgart.

    So in a decade when these are ubiquitous and most of the world is a desert, suddenly the Fraunhofer Institute will announce they had a patent on this and anyone drinking the water will have to pay licensing fees. [wikipedia.org]

    Great, just... great.

  • Isn't this what Luke Skywalker's uncle did for a living? I thought it was a given that you could condense water out of thin air.... My refrigerator does this all the time.

    • by fuzzyfuzzyfungus ( 1223518 ) on Tuesday June 09, 2009 @07:55PM (#28273307) Journal
      The trick in TFA is pulling water out of the air without keeping parts of your apparatus below the dew point, which takes a fair bit of energy. There are still some active parts, looks like mostly pumps, and some solar heating; but no refrigeration is required.

      If you have massive energy to throw at the problem, it is trivial(like a great many problems), solving it with relatively little energy is the real trick.
  • by jdb2 ( 800046 ) * on Tuesday June 09, 2009 @07:32PM (#28273131) Journal
    There was a story posted about fog capture for drinking water -- "fog nets" -- back in 2000 :

    Fog Collection As Sustainable Water Source [slashdot.org]

    jdb2
  • by CuteSteveJobs ( 1343851 ) on Tuesday June 09, 2009 @07:36PM (#28273163)

    > Frank Herbert's Moisture Traps May Be a Reality

    No Kidding. The Jihad is a reality too.

  • by Dasher42 ( 514179 ) on Tuesday June 09, 2009 @07:46PM (#28273241)

    Here in California our snow packs are dwindling year after year, which means our valleys are likely to revert to their natural desert climate. That's where a full third of our nation's food comes from. We might want to consider some windtraps, not growing rice in a desert, or maybe borrow some Australian expertise to do something cool [youtube.com].

    • "That's where a full third of our nation's food comes from. "

      That does not necessarily mean that it should come from there forever. Just as the Rust Belt de-industrialized over decades, California could reduce the amount it farms. The employees can go back to Mexico and the owners can invest in something (or someplace) different.

    • by Hadlock ( 143607 )

      When we finally raze detroit to the ground we'll have acres and acres of prime farming land just minutes away from the largest source of fresh water on the continent.

  • active vs passive (Score:5, Interesting)

    by TheSHAD0W ( 258774 ) on Tuesday June 09, 2009 @08:17PM (#28273487) Homepage

    The problem with this design is it requires electricity, which means expensive solar cells and periodic maintenance to clean them off.

    The moisture traps mentioned in Dune already do exist, and are entirely passive. You need an underground chamber with a few vents in the sides, and vent in the top with a chimney. The air rises in the chimney creating a constant flow of air into the chamber, and moisture condenses due to the cooler conditions in the chamber than outside.

    • Re: (Score:2, Insightful)

      A system based on these principles wouldn't require energy in the form of electricity, despite the mention of photovoltaic cells. The energy needed to lift the brine to the collectors can be provided by the dilute solution leaving the collectors headed for the underground distillation section. More mass leaves the collectors than enters them, compensating for some energy lost to friction. Given the effects of the salinity of the solution and the availability of solar energy for heat, I don't think the vacu
  • don't trust them. they'll let the concept out then they'll hit you up for license fees later on.

    "its a trap"

  • This method seems to result in pure distilled water which is generally considered harmful as your sole water supply. It's lacking in minerals that the body uses and also will turn acidic naturally. I guess since you're IN a desert though, they could scoop up a few spoonfuls of dirt and mix it in with your nice clear glass of fresh water. :-)

    • This method seems to result in pure distilled water which is generally considered harmful as your sole water supply. It's lacking in minerals that the body uses and also will turn acidic naturally.

      I learned this in geology class, but apparently it's not universally accepted as true anymore. If you can find a reliable cite to support it, I'd be interested in reinstating my previous belief though.

  • by petrus4 ( 213815 ) on Tuesday June 09, 2009 @08:46PM (#28273707) Homepage Journal

    I live in southeastern Australia, and down here, we haven't had regular rainfall now since 1995. Melbourne's water reserves are currently sitting at around 25%. The government's been talking about dredging the Yarra, the city's river, and that is only about a third of peak level at the moment as it is.

    This tells me that the long term trend for Victoria is desertification. Queensland is getting floods these days, while we get barely a drop. Unless we're planning on abandoning the entire state, we're going to need technologies exactly like these, in order to be able to continue to live here.

  • by PhantomHarlock ( 189617 ) on Tuesday June 09, 2009 @10:00PM (#28274197)

    When I read this article I was expecting to see another machine based on the ammonia absorption cycle. I was pleasantly surprised to see something new. This is interesting and should be followed to see if it becomes reality.

    It's been possible to build an air-water condenser using the ammonia absorption cycle since the 1800s. Blow air across the cold outer surface and the heat exchange causes condensation. A gentleman proposed "oasis machines" which would be a condenser hidden in a decorative pool / fountain from which local villagers could draw water. It was self contained and needed no outside electricity, perhaps solar. He proposed it as a solution to providing water to villagers in Africa, etc. A poster above did mention the problem of the water lacking in mineral nutrients.

  • by Anonymous Coward

    ...was to effectively trap the wind emerging from slashdotters.

  • Quite a lot... (Score:4, Interesting)

    by johndmartiniii ( 1213700 ) on Wednesday June 10, 2009 @06:06AM (#28277219) Homepage
    ...of water in the desert air, apparently.

    The caretaker of my building in Cairo directs the water that condenses in all of the air-conditioner units in the building into the gardens. While it isn't energy efficient AT ALL, I am always surprised by how much water gets to the garden. And as the weather gets hotter, the residents use their air-con more meaning more water for the garden. Again, it's not energy efficient in any way, but it does save water by reclaiming it from the air, and quite a lot of it.
    • Re: (Score:3, Interesting)

      by evilviper ( 135110 )

      I am always surprised by how much water gets to the garden.

      Humidity is relative. A desert can have much more moisture in the air than a much colder, much more humid area. It's just that, at 50C degrees, the air can hold much more water than it can at 10C degrees. So the same amount of water that makes the desert 15% relative humidity, can result in rain (100% relative humidity) in colder climate.

      It's the same thing that allows far more sugar/salt/jello/etc. to dissolve in warm water than cold...

  • Beware, It's a trap !

    (sorry)

  • by Catbeller ( 118204 ) on Wednesday June 10, 2009 @01:00PM (#28281629) Homepage

    Frank Herbert, while speaking in a radio interview on a call-in show around 1984, said that he saw a pilot project of a desert moisture collector while he was doing research as a journalist back in the Sixties.

BLISS is ignorance.

Working...