Distilling salt-water?

Discussion in 'Water Filtering & Storage' started by Raven348, Oct 22, 2008.

  1. Raven348

    Raven348 Active Member

    If I'm stuck on an island with no water is it feasible to boil salt water and collecting the steam for drinking (after the steam has cooled down it will be distilled water) or would that take forever make all the water one needs?
  2. Blister

    Blister Active Member

    Yes. Anywhere there's water, there's the possibility of distilling it provided you have the materials. You'll need a heat source, container for boiling, some type of collector and a condenser to condense the steam back into water. Unfortunately, that stuff may not be on your island. The best bet would be to go to the center of the island and try to dig down to water or look for another natural source like rain puddles, ponds or streams but remember, there's a high probability of parasitic infection drinking from standing water pools.

    It would probably take far too much wood (fuel) to condense enough water to sustain yourself without proper equipment though. Probably not the best method if you're randomly stranded.

  3. android

    android Guest

    I was watching survivorman and he found some garbage, and made a solar distiller thingy i.e. basically found a cup, put the cup in the center of found container, poured water in the container thing, covered with plastic, then pressed the center of the plastic so all the evaporation would drip into the cup...

    Best way would be collect dew or rain
  4. JeepHammer

    JeepHammer Well-Known Member

    I lived in the Fla. keys, and all the 'City' water there has to be piped in from the mainland... It's EXPENSIVE!

    Most of us had rain water catchment systems...
    Lots of smooth tile, slate or metal roofs, and lots of storage 'Cisterns' like the older homes before the days of 'City Water' had...

    It's basically a 'Tank Well',
    Large storage tank underground or set on the ground designed to catch all the CLEAN rain water it can.

    That is used as is for household water, washing dishes or cloths
    (hence my habit of sloshing some bleach in the dishwater that I do to this day)
    And running it through a commercial filter before drinking or using it for ice...

    Most 'Drinking Water' is 'City Water', most 'Utility' water is from the cistern.

    Boiling water and condensing the steam (water vapor) is called 'Distilling' and it's wildly ineffective way to either remove parasites or salts from drinking water, but it's still done to this day...

    Instead of boiling water to distill it, try a 'Solar Still'...
    Works the same way, little different arrangment, and takes NO fuel except the sun to work.
  5. JeepHammer

    JeepHammer Well-Known Member

    Diagram of simple solar stills,

  6. Blister

    Blister Active Member

    Thanks for the diagram JH. That's awesome. Yet another reason to have packaged plastic stored with our other goodies.
  7. JeepHammer

    JeepHammer Well-Known Member

    No problem man! I was meaning to diagram these out and take some pictures for my own 'Survival' section of my web site, and I though I'd add it here for you guys...

    Last one I made was with a 99¢ rain poncho from Wally-World.

    The one before that was a garbage bag split down one side.
  8. Raven348

    Raven348 Active Member

    I have researched solar stills now and the concept is way better than making a fire for heat. Even though its slower one can simply make more or bigger stills.
  9. JeepHammer

    JeepHammer Well-Known Member

    Doesn't matter if the solar still is the size of the porch roof, if it's up out of the way, and it works without anyone messing with it, then what is the issue?

    We use one about the size of a large folding table and it produces about 5 gallons a day in summer heat,
    It's design and construction was optimized for what it is doing!

    Black interior, angled to the sun, super clear glass on top, all the things you can't ensure from a survival solar still.

    You can't expect that kind of production from a makeshift 'survival' still!

    The one draw back to a solar still I can think of,
    You production goes WAY down in cold weather,
    And you can't use the above ground type in real cold weather.
    This is a '3 Season' type of thing...
  10. seagrape

    seagrape Active Member

    I remember from years ago that, in a survival situation, you can use plant material as your source of water. Never tried it but, as I remember, you dig a pit, place a container in the middle of it, add plant material into the pit. Then place your plastic over the top of the pic and press the center of it down into your catchment container. The water in the plant material will evaporate, condense on the plastic and drain down into your container.
  11. Emerald

    Emerald Well-Known Member

    You can encapsulate whole branches of living plants and have a catchment at the bottom of the plastic and during the day the plant it self will give off moisture and it will collect in the bottom of the catchment. the best thing to do with it is run it thru some charcoal if you can. and yes there will be bugs in it.
    I watched a show a long time ago on what can you do in desert to make drinkable water. They all had the same charcoal filter and each scientist had to find a way to get water.. Some dug dry waterways till they hit mud and some did the night moisture condensation and the all did something different.. the one lady did the plant/plastic. Not only did she get the most water but when it was all passed thru the filters the one that tasted the best was the plant water.

    But if on a desert island with no water.. you can do the solar still at the edge of the beach. dig big pit till you hit water.. sure it will still be salty at this point and do the cup/plastic tent thing in full sun.. the salt water will evaporate and if you put a rock/weight on the plastic right over the cup and every so often tap the plastic lightly to get it to fall into the cup.
  12. Londoner

    Londoner Well-Known Member

    Most commercial desalination plants use Reverse Osmosis but you are not going to find the bits to build a plant on an island. However, its worth reading up on RO systems. You can get small domestic systems. even if you do not ever use one all knowledge is power
  13. BlueZ

    BlueZ Well-Known Member

    Its not that difficult to set up a distillation process.
    Just remember that the resulting water willbe distilled and probaly benefit from having a tiny amount of the sea salt added back to it
  14. JSank80

    JSank80 Newbie

    I think the biggest issue will be what do you have on hand on the island, and how long do you think/hope/plan on being there. Limited supplies and time, solar still is very quick and effective. If you have the materials to set up a still, your only limited to how much fuel you have, because it's not like you're going to run out of salt water.
  15. readytogo

    readytogo ExCommunicated

    clean water




    Everybody needs water, spend six years in the field, swamps, rivers ,snow, all kinds of filters and ways to cook water, but to be honest salt water is not easy to deal with, you will need some kind of tool to make it drinkable,and before you search for water or start digging a well you better have some water or you will not make it.
  16. BillS

    BillS Well-Known Member

    Distilling salt water is very fuel intensive. It also means you'll need a fire going for a long time and the smoke could give away your location.
  17. LincTex

    LincTex Jack of all trades?

    Long term, no good solutions. All plastic breaks down in the sunlight, some won't even last a year. I hope help is on the way :(

    I keep thinking of Cast Away and how hard that situation would TRULY be to endure.
  18. helicopter5472

    helicopter5472 Well-Known Member

    I'd say if your plans to BO on an island, are your plans, prepare now, they make smaller units for boats, these of course take electricity, so think of all you may need, ie; small genset/fuel or solar and batteries, and manual generator, like a pedal bike, ect. get backup stuff to make solar types and all the stuff you need to survive on an island. Be prepared like a Boy Scout, (well keep an eye out for some of them if ya know what I mean) If this is just a random possibility of island hopping, refer back to the Boy Scout thing, and bring lots of water. Plan B- hope for lots of rain, or plan on movin on. Cause Plan C probably isn't very pleasant and doesn't end well :D
  19. Highwater

    Highwater Highwater Filters

    If you've got plenty of fuel, the Vortex is a good way to go.

    Katadyn makes reverse osmosis desalinator but they are very expensive.
  20. readytogo

    readytogo ExCommunicated

    You mean you never distill collected water for drinking, that is a wasted.