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Desalination new method

  1. Jun 22, 2015 #1
    If sea water is confined in a vacuum of 600 Pascal pressure it will boil and cool until ice forms. There are several problems designing a system using this process. But, when all the engineering is done and a practical system is developed this method will produce potable water from seawater far more efficiently at less cost than the best currently available system. How can interest in developing stuff like this be generated? thanks
     
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  3. Jun 22, 2015 #2

    billy_joule

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    That sounds like the traditional method for desalination to me;

    https://en.wikipedia.org/?title=Desalination
     
  4. Jun 22, 2015 #3
    Billy, This method you describe is not anything the same thing I am suggesting. The vacuum I am describing will produce ice as well vapor and has a operating temperature at ~-5/+5C. You need to study these systems to see how well they really work.
     
  5. Jun 22, 2015 #4

    billy_joule

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    Maybe you could provide a link or more information on your proposed system?
    My intuition tells me making ice when you want water will not be competitive, efficiency wise, with traditional desalination. I don't see how reducing the temp and/or pressure until freezing occurs will be of much benefit, the enthalpy of fusion will be wasted energy (unless of course the icebox comes back into vogue!).
     
  6. Jun 22, 2015 #5
    Your instincts are right if you a think about it in conventional ways like they say when using in use methods. I am saying that by making the vacuum and then using raw seawater or waste water or brackish water the ice can be made as vapor is removed and condensed. I never posted anything on line about this as far as I recall, but I did write the DOE several times. They never commented because it was not will enough developed. It's a big job as you might know involving millions and lots of engineering. Lately I've been working on some of the details like how gravity can be involved in the vacuum chamber and how to get the ice out. I know how the vapor needs to be removed as well as about how much energy is required to do the job.
     
  7. Jun 22, 2015 #6

    berkeman

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    Yes Jim, you need to post links to published works about the method you want to discuss. What is your training in engineering and thermodynamics so far?
     
  8. Jun 22, 2015 #7
    Hi Billy, as I implied in my posts here as far as I know nothing has ever been published about this.
     
    Last edited by a moderator: Jun 22, 2015
  9. Jun 22, 2015 #8

    berkeman

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    Okay, Jim, if nothing has been published about it before, and your idea is unique, non-obvious and useful, you should be careful about talking about it in public forums. That can nullify any patent possibilities for the process. It's important that you protect your idea as you develop it, so that you can profit from your ideas when they work. I'd recommend that you talk to a local consulting engineer to help develop your idea. He or She would be able to talk through the thermodynamics of your idea, and let you know if your idea has merit or not. If it has merit, the consulting engineer will help you keep your idea private until the patent applications are filed.

    This thread is closed.
     
  10. Jun 24, 2015 #9

    berkeman

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    Thread re-opened at the request of a subject matter expert. :smile:
     
  11. Jun 24, 2015 #10
    Hi Expert, As an expert you know these systems have been around a long time and the best system is nature's own powered by solar. We humans don't hold a candle to natural ways of purifying water. Many types of systems have been designed and all of them cost too much for general use.The least costly way currently available is R.O. for stand alone systems. It seems to me a much more efficient(cost wise) way to make potable water is a freeze system. This method has never been researched in any depth because water has never been that great a problem. We just wait for rain or make canals the Romans would be proud to own or just move to greener pastures. Anyway, I don't have any intellectual property worth patent protection or money to invest in pursuit of it. I do know the physics indicates what I have posted above can be obtained with current state of the art and potable water can be produced at a much lower cost than it is being done at this time by the best man made systems.
     
  12. Jun 24, 2015 #11
    Firstly, I am not the expert, but I am following this topic.
    I would like to know why it is that freezing the water after having purified it has an advantage,
    or is the freezing necessary as part of the purification method?
     
  13. Jun 24, 2015 #12
    Freezing purifies water just as vaporizing does.
     
  14. Jun 24, 2015 #13
    Are you sure about that?
    Sea water freezes naturally in polar regions, and the resulting ice contains a lot of NaCl seasalt plus other impurities.
    Maybe you have a special method of freezing though, and if so you won't want to reveal the details before having patented the process.
     
  15. Jun 24, 2015 #14
    Quite sure of this fact. Sea ice has all kinds of stuff not related to the fusion of liquid to solid.
     
  16. Jun 24, 2015 #15
    Hmm, yes I did quick fact check on sea ice, and it seems that although newly formed sea ice has a high salt content, if it remains frozen for several years the impurities slowly leech out of it.
    If you have discovered a way to accelerate that process to be effective in few days rather than years it does seem plausible.
    Let's wait and see what the expert who asked for this thread to be reopened has to say.
     
  17. Jun 24, 2015 #16
    Rootone, I just said there is nothing new and therefore patentable here. The area has never been explored much like most of our planet which is undersea-but I digress. I don't have time or money to pursue intellectual rights. As for the salt problems-they are minor compared to real problems engineering might resolve in time.
     
  18. Jun 24, 2015 #17

    russ_watters

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    I'm not the expert either, but I also think this is wrong and would like an explanation.

    Vaporizing water is, itself, a purification process: when the water evaporates, it leaves the impurities behind. Not so with freezing: when water freezes, most impurities freeze with it.

    So if you have a method for removing the impurities from ice that is already formed, that would be a wholly different (and useful) thing. Is that what you are suggesting?
     
  19. Jun 24, 2015 #18
    Hi Russ, Try a simple experiment you can do at home-put a quart of milk or orange juice in the freezer compartment of you refer. In a day or so you will find ice on top and muck on the bottom-the ice can be examined anyway you wish and it will be pure H2O. What I am suggesting is developing a method of moving heat from seawater by evaporation cooling it to a point where ice forms. Nothing more than that. It is a very simple well researched process.
     
  20. Jun 24, 2015 #19

    russ_watters

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    I have done this: in my freezer right now is a bag of Gatorade Cubes I use for biking. When I freeze them, a small portion remains muck and I use that in the next batch. The rest is frozen Gatorade.

    Kids also make popcicles this way.
     
    Last edited: Jun 24, 2015
  21. Jun 24, 2015 #20
    Hi Russ, OK you win-its something I did as a kid too. The ice in the Popsicle is still ice as is the ice in the gator aid and the sweet stuff in not ice. This is a very interesting bit of physics best for some other thread. Its really way off the point here.
     
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