Beth Conrad, a 12 year old female from Hong Kong asks on October 7, 2003,How can I build a water purifier?
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A quick search of the Internet turned up a number of possibilities. In developing countries around the world people are making ceramic water purifiers. These take a bit of work, but they are very cheap, costing less than one dollar to make. Details on how to make one at home are available here.
A standard way of purifying water is to distill it. You boil it, then condense the steam and collect the water. A simple distillation aparatus can be made with a kettle and a coil or column of tubing. A typical setup can be seen at Journey To Forever, based on a design first published in Mother Earth News.
A cheap way to distill water uses the sun's energy to evaporate the water which condenses on a sheet of glass. Plans for such a still can be found at PermaPak. Variations of all these ways, such as making a still from a black paper cup and a plastic bag, are all possible and are left to your imagination.
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