[Stoves] solar still

[frank]

See Images at: http://www.bioenergylists.org/en/shieldsstill 

Pictures:
1) four units lined up
2) reflector placed in position on back
3) electric heater we added so it would work later into the night (not
necessary)
4) back side of reflector. Has a light weight structure frame to maintain
its shape. Reflector is just shinny metal.
5) U shape collector and pipe to remove the distilled water to storage tanks
6) Inflow pipe on left side, out flow on right
7) picture of all from other end


Stovers and clean water people;

I found some more info on the solar distillation unit we installed in 1985
and used until we moved into a larger building.

Each unit is 6' X 3'

The slope is from the box being 5.25" along the back long side down to 3"
along the front long side. So 0.75" per foot" The glass is 'ground glass' on
the underside.

The collecting is along the lower front in a stainless steel U.

There is a reflector along the long high side to reflect the sun onto the
glass. The water tray inside is stainless steel and left shinny (not black).

It works by a pool of water that is heated from the sun then condenses on
the underside of the glass due to cooler air flowing over the surface. The
water hangs onto the glass and slowly moves down the slope to drop into a
stainless steel U. The unit is complete sealed with silica glue.

This is what the contract stated:
The unit will generally give 2 gallons per day.
An automatic feed water system, time clock operated, connected to your
municipal water supply Brine flush lines to waste Product (distilled) water
to your reservoir.

The solar still feed and brine flush water requirement is approx. 12 gal per
day.  Will work for up to two days without power then the feed water can be
hand filled if needed to prevent the pan from drying out. In the event the
glazing will lose its hydrophilic quality ammonia hydroxide is added to the
feed water and approx two weeks needed to re-establish properties. (note: we
never had this problem once the two weeks got it started. for the several
years we used it.)

If seawater is used the daily feed water requirement increases from 12 gal
to 18 gal per day..

We used four units and got about 9 gal per day total in this Calif climate.
We also added low watt heaters to keep the units running later into the
night before the flushing and feed water replacement.

I have pictures of the abandoned units that have been left on the roof if
anyone is interested.

Frank
-- 

Frank Shields
Soil Control Lab
42 Hangar way
Watsonville, CA  95076
(831) 724-5422 tel
(831) 724-3188 fax
frank at compostlab.com
www.compostlab.com