Chemical sea-water desalination
Are there any known/designable liquid chemicals that can be added to sea-water that would absorb water into its molecular composition whilst density dispersing the saline impurities to enable seawater desalination an affordable means of obtaining clean drinking water?
QUOTE (momentito+Jan 8 2008, 09:47 AM)
Chemical sea-water desalination
Are there any known/designable liquid chemicals that can be added to sea-water that would absorb water into its molecular composition whilst density dispersing the saline impurities to enable seawater desalination an affordable means of obtaining clean drinking water?
yes there is, and already invented, new tablets have been made that enable ANY liquid , let it be pee, to transform into drinkable water
click here to see the website
also here
these websites may be lies, but i have seen a vid on tv!!!
Are there any known/designable liquid chemicals that can be added to sea-water that would absorb water into its molecular composition whilst density dispersing the saline impurities to enable seawater desalination an affordable means of obtaining clean drinking water?
yes there is, and already invented, new tablets have been made that enable ANY liquid , let it be pee, to transform into drinkable water
click here to see the website
also here
these websites may be lies, but i have seen a vid on tv!!!
Vacuum solar desalination.
In coastal desert regions where temperatures are high, water could be evaporatively distilled with the heat of sunlight shinning into plastic tanks of seawater in a vacuum. With zero atmospheric pressure the water would boil very quickly with solar power. The steam would be condensed in a water refinery as clean drinking water.
In coastal desert regions where temperatures are high, water could be evaporatively distilled with the heat of sunlight shinning into plastic tanks of seawater in a vacuum. With zero atmospheric pressure the water would boil very quickly with solar power. The steam would be condensed in a water refinery as clean drinking water.
I prefer the "Waterworld" method...ha... 
QUOTE (einstienear+Jan 8 2008, 03:09 AM)
yes there is, and already invented, new tablets have been made that enable ANY liquid , let it be pee, to transform into drinkable water
click here to see the website
also here
these websites may be lies, but i have seen a vid on tv!!!
let it be pee???
hehe, a great thing to have if your lost in the desert I suppose?
click here to see the website
also here
these websites may be lies, but i have seen a vid on tv!!!
let it be pee???
hehe, a great thing to have if your lost in the desert I suppose?
When in times of trouble...Mother Mary comes to me....there will be an answer....let it pee ...let it pee lol
~~~when ye find yourselves in times of trouble...mother Mary comforts thee! bringing words of wisdom...let it peeeee~ let it pee!thanks for the laugh...and to think I was off looking for something to bring back on the water desalination in Milolii Hawaii. How boring am I?
You are making buns? Ferry funny!
Distillation by sun heat can be a very simple means of getting a little bit of drinking water on a lifeboat.
To get more significant amounts, optimized units work at several pressures (hence temperatures) so that the condensation heat of distilled water evaporates sea water at a somewhat lower pressure. You need heat from the Sun only once.
Planning such a project generally involves producing also electricity and home heating from the steam.
However, distillation methods are always expensive, because water absorbs an awful lot of heat to vaporize.
All modern processes use reverse osmosis:
http://en.wikipedia.org/wiki/Reverse_osmosis
as it takes far less energy since the water isn't vaporized.
Alas, even reverse osmosis is expensive. Some of Spain's tourist cities (on the Costa Lotta) use it to feed (¿apastecer?) homes, as this is a requisite to attract tourists. Adelaide, in Australia, has such plans. But agriculture can't rely on this - emirates do have some farms, but profitability isn't their prime goal.
Distillation by sun heat can be a very simple means of getting a little bit of drinking water on a lifeboat.
To get more significant amounts, optimized units work at several pressures (hence temperatures) so that the condensation heat of distilled water evaporates sea water at a somewhat lower pressure. You need heat from the Sun only once.
Planning such a project generally involves producing also electricity and home heating from the steam.
However, distillation methods are always expensive, because water absorbs an awful lot of heat to vaporize.
All modern processes use reverse osmosis:
http://en.wikipedia.org/wiki/Reverse_osmosis
as it takes far less energy since the water isn't vaporized.
Alas, even reverse osmosis is expensive. Some of Spain's tourist cities (on the Costa Lotta) use it to feed (¿apastecer?) homes, as this is a requisite to attract tourists. Adelaide, in Australia, has such plans. But agriculture can't rely on this - emirates do have some farms, but profitability isn't their prime goal.
Milolii uses solar to desalinize about 1000 gallons a day for the small fishing village.
http://www.ibiblio.org/london/permaculture...2/msg02525.html
http://www.ibiblio.org/london/permaculture...2/msg02525.html
Whoever invents the cheap simple method on a large scale will rule the world. Water availability will eventually be our greatest challenge. "Global Warming" will be a non sequitur. If ever a scientist wanted to make a pile of money, this is it.
Milolii: Nice project.
However, complete computations support the idea of converting sunlight to electricity by a thermal means, and use the electricity in reverse osmosis.
Not quite as direct and elegant... But better efficiency per m2 and per $.
There are also projects to produce electricity from temperature differences between surface and depth in the oceans (tested in Hawaii as well, I think). Many of the processes make fresh water as a by-product, which is seen as a decisive advantage.
One stupid obstacle is that as soon as you have pumped cool water from deep in the ocean, people don't let you use it to produce electricity: they want it immediately to keep the air and the lobsters cool in their restaurants.
However, complete computations support the idea of converting sunlight to electricity by a thermal means, and use the electricity in reverse osmosis.
Not quite as direct and elegant... But better efficiency per m2 and per $.
There are also projects to produce electricity from temperature differences between surface and depth in the oceans (tested in Hawaii as well, I think). Many of the processes make fresh water as a by-product, which is seen as a decisive advantage.
One stupid obstacle is that as soon as you have pumped cool water from deep in the ocean, people don't let you use it to produce electricity: they want it immediately to keep the air and the lobsters cool in their restaurants.
we use desalination plants here. good value for yen per water unit. recommended they are please. You must try.
QUOTE (einstienear+Jan 8 2008, 10:09 AM)
yes there is, and already invented, new tablets have been made that enable ANY liquid , let it be pee, to transform into drinkable water
these websites may be lies, but i have seen a vid on tv!!!
Where did you find info, that these tablets will make FRESH water from SEA water?
these websites may be lies, but i have seen a vid on tv!!!
Where did you find info, that these tablets will make FRESH water from SEA water?
Forget chemicals - generally speaking, dry places are areas which receive lots of solar energy. Why not utilise this energy to evaporate pure H2O from saline source, condense, and pump to where required?
In the most recent issue of Discover magazine they show the price of fresh water versus desalinated water. They show the price curves moving towards each other steadily over time. In fact, they show them nearly approaching each other in the present time.
I was really curious if this was an accurate bit of reporting, or hyperbole. But if it is accurate reporting it means that we are already at the point where it makes sense. A small amount of research right now indicates that they were probably ignoring the distribution costs for the desalinated water, and counting distribution costs for rain/pumped water, so it was not entirely honest.
googling today it appears the cost of 1 cubic meter of drinking water depends on the country. In some countries, the cost is about 2 bucks for this meter of water, and the cost of desalinating is 0.5 bucks for that meter if it is in a suitable location.
It appears the 2 bucks is largely for distribution costs of the original meter of water. Thus, we can see that it already is pretty cost effective- at least in Germany, it is only increasing the price by around 12%
In the United States, it roughly doubles the cost of the water to desalinate it. So it is all a matter of price. As the available supply of fresh water diminishes, more and more will be desalinated.
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