I don't know about him in Central FL but in South GA the water you pump
stinks, literally! Its loaded with H2S. Also with more people pumping the
ground water the more problems there are.
Or maybe 5/8 m^2, with 8 effects.
How about a stack of transparent trays with sun shining into the top?
Water evaporates from each lower pond and condenses under the pond above.
Would you believe a factor of 8? :-)
Hodges, C N, Thomson, T L, Groh, J R [who also worked on insulating
greenhouses by filling the poly pillows with soap bubbles], and
Frieling, D H, (1966), "Solar Distillation Utilizing Multiple Effect
Humidification," Environmental Research Laboratory, University of
Arizona, Tucson AZ, a 159 page report.
A partial description from Meinel and Meinel's "Applied Solar Energy":
An efficient multiple-effect solar distillation system was designed by
Hodges et al (1966)... A pilot plant constructed at Puerto Penasco,
Sonora, Mexico, produced 19,000 liters/day (5000 gal/day) from a simple
solar collector of 1000 m^2 (10,400 ft^2). The solar collector [was]
a series of long shallow ponds of water covered by a single layer of
plastic [with another floating layer]... stretched tight because the
air pressure inside the collector was slightly above atmospheric...
[ie the top layer was statically inflated with a small blower. The bottom
layer was black polyethylene plastic, lying on leveled desert sand.]
The multiple effect in this system was obtained not by pressure gradients
but by simply reusing the airstream that was dehumidified by the cooling
water [incoming sea brine, which was heated by outgoing condensate.] After
a first pass through the hot water in the evaporating tower, the water
vapor was condensed out by the cooling water system, this "dried" air
being again passed through the warm water in a lower section of the tower
and rehumidified for subsequent condensation in the cooling portion of the
system. The net result was a multiple-effect system that effectively used
***one eighth*** of the heat of vaporization to distill one gram of water.
The Mexican system used a 50' tall tower packed with 3" plastic rings for
the evaporator, and a tower full of fin-tube pipe next to it as the condenser,
in a counterflow system with multiple horizontal "bleed through" air ducts
at 5 different heights connecting the two towers. Is there a simpler way, eg
one with a plastic film greenhouse and wastewater ponds and plants?
thanks Duane, I am going to build this for sure. distilled water is by far
the best to drink. I had thought about building the trough on a purpose
built cart, so i can move it around, to saftey in canes.
i would have the trough on a two axis mount, one a tracker and one a maual
My wife is a good cad operator, so will flesh this out a bit more for
everyone to critasize.
You might not need a second axis adjustment if your trough is oriented
north-south, tracks east-west and has a mirror on one end.
I am still of the opinion that a trough is overkill to distill water.
You don't need the high temperatures a trough will provide to evaporate
water and a less complex device has fewer things to go wrong.
If you can distill enough water, you might want to consider using it
for bathing, or at least washing out hair. Water cleans better when
it isn't full of stuff already.