How is water de-salinated, and how can it be accomplished?

Question

without the need of some purification system, in other words, if I was stuck in the middle of nowhere, how would i de-salinate water.

Answer 1

With the help of a process called distillation

Answer 2

Boil it and collect the steam given off, and condense (cool) it off and, hey presto, palatable drinking water.

Answer 3

Stanners has it about right. Other methods may include a solar still. Same idea, except less work. Dig a hole near but above the high tide line, put you cup in the bottom, put a non permeable material over it, like plastic from a bag. Put a small stone in the middle right over the cup. Do this all where it is in the sun.  The sun will vaporise the water, the water will condense on the non permeable surface (the plastic) and will condensate and run down hill (the low point created by the stone) and drip into the cup. Makes about 1 cup a day per solar still. You will be so happy that the beach is covered in washed up plastic bags and tarps, the hard part will be finding something to use for a cup. But then some old Styrofoam cups should be on the beach too.

On my boat I have a reverse osmosis water maker. It drives the water through the membrane leaving the salt behind. But on the boat I don't have a beach to work from. These solar stills can be made so they float and work too. They used to sell an inflatable model for use on life rafts.

Answer 4

Large scale desalination plants works on two principle.Multistage flash evaporation.Where salt water is heated from the exhaust steam of a turbine,boiled under low pressure,then condensed to water.The other method is Reverse osmosis. Here water after first filtering through a fine filter,pumped through membranes at high pressure.

This removes salt.