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What is the fastest most energy efficient way to evaporate seawater on a small scale and collect the salt that reminds? Answered

I tried standard sun evaporation in trays (1 gallon) and it takes far too long (not to mention all the debris that collects in the water during the evaporation process). Heating it over the stove uses too much energy. I am thinking a solar fan / heat combination. Your thoughts? (Note: The goal is to collect the sea salt.)



7 years ago

Buy a solar still like this:

For 60$ you could get 1,5 liters/day of clear water with standard procedures.

I know that the price should be lowered a lot for third world consumption, but at least it is a product that works!


In Hawai'i its done on a rock bowl shape for the white salt or right in the Red Dirt for the red salt. Google around

The sun, exactly but as water is 'clear' a method of having a flat try, with a dark bottom, covered with glass to trap the reflected light, but with air moving between them (like you say with a fan) to evaporate the water. A fresnel lense or solar death ray could concentrate the sun into a piping hot insta-boil solution for small quantities at a time.

If you cover it with glass, the water will condense and go back into the solution, but I like that idea. Try a solar still. Those are made to trap heat and evaporate water efficiently while separating the water.

I would leave out the fan-it's going to cool the sea water off and reduce evaporation. After concentrating the salt, I'd boil off the rest by putting it in the oven so that the bottom of the pan doesn't get hot enough to scorch-probably when cooking something else so as not to 'waste' any power : ) Or, you could use the wicking effect, but I'd use something very clean and thin with a fan on it, then wring out the concentrate or carefully scrape the crystals off the edge.

just if the container is covered, the water will re-condense back into solution - it would only need to be a small fan, like gpu fan size (5cm) running on far less than a watt to ensure fresh air flow.

Suspend over the tray a piece black cloth folded into many layers, with the bottom edge lying inside the tray. Evaporation will take place quickly on the large surface area of the cloth, and capillary action will draw up new seawater to replace it.