Earlier quoted context omitted.
Regarding remote locations- they usually lack water altogether. A long time ago, as a kid i read about a experiment in a GEO-magazine harvesting water directly from air. The used idea was a hygroscopic chemical (Silicagel) collects the moisture from the air. Sunlight heats the silica gel- which releases the moisture as steam- which then condenses in a destil. It was very little water for a lot of effort, but the comp…
You can make a solar still without desiccants. Dig a hole somewhere that will get sunlight most of the time, drop a cup in the bottom to catch water, and create a funnel with a plastic sheet. (If you don't have a plastic sheet, branches can work.) There are various ways to optimize it, but a single water trap isn't going to keep a person alive.
Simple, solar-powered water desalination
151–160 of 205 posts
Re: Simple, solar-powered water desalination
#152Earlier quoted context omitted.
One fascinating (well, to me) component of modern RO desalination systems is the rotary pressure exchanger. Such a simple device, but so important. It looks like something from the 19th century, but the base patent was issued in 1988. https://en.wikipedia.org/wiki/Pressure_exchanger
I found this video which seems to animate the concept nicely: https://www.youtube.com/watch?v=udffed4Pq3g
Re: Simple, solar-powered water desalination
#153Efficiency in desalination is measured by comparing the energy expenditure to the enthalpy of vaporization of water (basically the energy required to distill water by boiling it). The current state of the art reverse osmosis desalination plants use about 3.2 KWh of electricity per cubic meter of fresh water ( https://pdfs.semanticscholar.org/d4d7/821d585699719289dddd10... ). This technology uses about 173 KWh of sola…
> For large-scale desalination, however, it is almost certainly more cost-effective to use solar panels, batteries, and large scale reverse osmosis systems. For large scale desalination, you need to attach tiny magnetic particles (think nano-scale) to the salt, and then extract it with magnets. And as a byproduct, you'll get Lithium.
Re: Simple, solar-powered water desalination
#154"than 1.5 gallons of fresh drinking water per hour for every square meter of solar collecting area." Units, people. Units. Be imperial. Be metric. Hey! Be both!
Re: Simple, solar-powered water desalination
#155Re: Simple, solar-powered water desalination
#156"than 1.5 gallons of fresh drinking water per hour for every square meter of solar collecting area." Units, people. Units. Be imperial. Be metric. Hey! Be both!
It comes out to about 0.4 liters per square foot, for those of you who are confused.
Re: Simple, solar-powered water desalination
#157Re: Simple, solar-powered water desalination
#158Re: Simple, solar-powered water desalination
#159Several pollutants I have in mind are VOCs and fluorine compounds.
Hopefully there is someone here that is qualified to answer this question.
Re: Simple, solar-powered water desalination
#160When I was in Boy Scouts loooong ago, there were instructions and diagrams for making solar stills out of a sheet of plastic, a cup, rocks and dirt.
It surely would require fairly specific conditions to work well; a wet ground and low humidity.