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In this instructable, I will show you how to purify abit of water when you are in the wild and trying to survive with 2 water bottles.
Step 1: Things you need
You need 2 water bottles. (If you find any in the wild)
Some duct tape or masking tape ( always carry some in any kind of outdoor trip)
Some dirty water or urine (really!)
Alot of sunlight
Step 2: Step 1
First take 1 bottle and fill it up with dirty water. Make sure that it does not leak outside the opening of the bottle when on its side.
Step 3: Step 2
Tape the other bottle to the opening of each other. Make sure that none of the contaminated water or liquid flows or leaks into the empty bottle.
Step 4: Step 3
Place the taped bottles in a area where sunlight is always shinning. Place the 2 bottles at a leveled area where there no slopes or leveled ground. EDIT: Sometimes you want to place the clean bottle abit upward so the evaporation can collect more better. But just a little bit so the purified water doesn't drain back to the dirty bottle.
Step 5: Step 4
Wait for most of the water to evaporate into the other bottle. (This might take more then 12 hours)
Step 6: Enjoy!
Carefully cut open or peel open the tape and drink the fresh water in the bottle that does not have the contaminated liquid.
Step 7: Wondering how this works?
Wondering how this works? Well....the contaminated water will go into evaporation because of the sun, the evaporated water will collect in the other bottle giving you fresh water.
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Nevertheless the point made elsewhere that if you have a source of heat to evaporate the water is a valid one, much quicker than the Sun. I think though that if you were dying of thirst you would risk a few of someones bacteria. (Probably safer than a kiss.) Or you could discard the first collection.
What worries me is why the water would selectively condense in the clean bottle. The primary bottle would always be cooler because of evaporation. I would cover the contaminated bottle with something black and cover the clean bottle with a wet cloth or wet soil (wet with contaminated water would do). In the wind this would evaporate and cool the clean bottle.
A tried and true trick is to cover a small container of dirty water standing in a bowl with a closed cylinder cut from a plastic bottle. Standing in the sun; the water condenses on the plastic and runs down into the bowl. This can be tuned with bits of damp cloth to be quite efficient. Except for the bowl you can make this all from one 2 liter bottle. Obviously several of these would be required to keep a person alive.
good one