How to Desalinate Seawater





Introduction: How to Desalinate Seawater

I can't believe there's a whole ocean full of water but we can't use it.So here's a way to desalinate seawater.It is best to try it on a sunny day early at sunrise;it will be done more or less in the afternoon.

Step 1: Prepare the Container

Use the big container and put the round black lid inside it.This is to atract sunlight.

Step 2: Add Recepticle

Place the small cup in the middle of the container on the black lid.

Step 3: Add Saltwater.

Add some seawater that you want to desalinate in your container but don't spill it in your cup.

Step 4: Cover With Plastic

Put the plastic over the container and fasten it with your elastic band.

Step 5: Small But Very Important Modification.

Add a small weight on the plastic right above the cup so that the plastic points down to your cup.

Step 6: Wait.

Wait for the water to evaporate, condensate on the plastic and trickle down and into the cup for you to drink.



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    i will try this if right well this can be a very money saveing for me

    Definitely a useful tool in a survival situation, but a solar still isn't something I would recommend solely relying on for water in a survival situation. They take a long time to purify a comparatively small amount of water and you're more likely to end up with far less water to drink than you expend over the course of waiting for it.

    A relatively simple way to expedite the process is to use a double boiler over a fire made of two metal containers ( you can substitute soaked birch bark cups or leather hides in an outdoor emergency, or really any container that won't burn or melt. ) and any sort of cone ( again, whatever yo can come up with. ) that you seal to the container with whatever you can find to keep the steam from leaking. By putting the whole deal over a fire, you will lose some evaporation through the seams in your makeshift still, but the increased efficiency of the whole thing will more than make up for it, with the added bonus of giving you a warming/signal/cooking fire to work with through whatever disaster you find yourself in.

    Awesome. Do you think you could do an instructable showing this process. And i have a simple question. Can you drink rain water collected or would it be wise to filter that as well. Thank you for your response

    Drinking rain water should usually be safe, but if you have the ability to distill or purify it, you should still do so. While it will generally be "clean" of pathogens, it does collect some level of dirt and other impurities like heavy metals as it falls to your collection vessel and in a survival situation, you're not going to be sure that your collection tools are clean. So while you can drink rainwater without a big risk, the number of things it contacts between falling out of the sky and going into you can result in potential sickness. Part of the point of purification that's often overlooked in discussion and survival guides is that you're not only purifying your drinking water, but also purifying the container you're drinking out of.

    You can't always afford to make fire, in survival situations.


    I don't understand. Do you mean that the enemy might find you?

    I believe he's referring to situations like being stranded at sea, or similar where fire would be either too difficult or dangerous to make, but those sorts of situations are VERY far and few between. As a rule, a fire is one of the best things you can have under survival conditions for a variety of reasons.

    Yes i completely agree. But. And this of course is a big but. If you were in end of times say and it was all out anarchy. She makes a valid point. What would be a trick for a fire to do the water desalination and keep the fire hidden. IE no smoke no signals that i dont want people to see that im there and have supplies for you to kill me for. Far fetched but valid.

    Here is something that I was taught in the survival course when I was in flight school: 1.) In beach situations find the high tide mark, 2.) Pace off 100 "yards" inland from that point, 3.) Dig down into the soil until you hit "water", 4.) Collect that "water" [it should only be a ~.5% to 1% saline solution (normal salinity is 3.5%)], 5.) Filter that collected water through any piece of wadded up cloth, 6.) Then if possible construct a solar still using that "water", 7.) Your solar still will be much more efficient & the untreated water can be used for cooking and personal hygiene.

    Awesome response. Taking notes my friend