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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default Potable Water - The Third Way.

Brian Whatcott wrote in
:


You've heard all about distilling water, and you've heard all about
reverse osmosis, but you haven't heard about low-cost, low energy
stills: they are brand new.

Briefly:
Take one forty ft vertical tube filled with saline.
Take one forty ft vertical tube filled with fresh water.
Connect them with a little engineering help - at the top.

The boiling point of water at sea level pressure is about 100 deg C

The boiling point of water at the top of a sealed 40 ft column of
water is near ambient.
So, it doesn't take much heat to boil the brackish water, and have it
pass to the fresh column where it is slightly cooled to hold the near
vacuum conditions at the boiling level.

[An engineering effort of a U of Utah group I think]

Brian Whatcott Altus OK


My deepest apologies to the engineers who may be rolling under their
desks, crushing their pocket protectors. It took me a while to stop
chortling. I nearly lost my Chinese dinner!

Psst...Brian....40'? What about the lake above 40', it's 400' deep and
above 40' ASL. It hasn't boiled away in millions of years from all that
pressure and lack of pressure.

In Tehran, Iran, my apartment was about 7000' ASL. Water DID boil at a
lot lower temperature. Making a cake at 7000' altitude is simply
amazing! ONE little cake mix makes 4 cakes!.....er, ah, after you clean
out the oven from putting ALL the cake mix in the pan, filling the oven!

But, alas, even at 7000', the water in my glass didn't boil itself at
ambient temperature, even at 110F out on the lawn!

Every engineering firm across the planet is going to be a jolly place
after hearing about this on Monday...(c;

Larry
--
Sure glad it doesn't work that way! We'd all be DEAD!