Guy_Incognito
Inactive
I've been looking at ways of improving your basic solar water still.
Say you have a bore/well with bad water in it. You get some water out of it and want to purify it. Now, a 20 or 30 foot column of water will lower the pressure enough that the water at the top of that column will boil at 50 or 60 degrees C or so.
If you :
- take an enclosed container/still full of dirty water, painted black in the sun.
- put a tap at the top, run a hose (coiled and cooled/shaded) into another sealed container.
- put a tap at the bottom of the container with a hose attached.
- drop the hose back down the bore to the water level.
- open the taps.
You'll end up with a partial vacuum in the top of the still, dependant on how deep your bore is. With that partial vacuum, you lower the boiling point / increase the evaporation rate of the water. So after you get the initial vacuum, you turn off the bottom tap for a while. You might be able to leave the bottom tap open in use, I dunno.
So you end up with vapour in the top of the still which will (er, should) condense out the cooler top pipe into your container. Vapour will still head towards the container, as it's sealed, and the same partial vacuum as the rest of it. When you want the clean water, you turn off the taps and take the clean container off.
The same sort of thing without the well could be done by hoisting the still up into a tree, or post. In that case, you might even be able to get away with just running the top hose back down to below the level of the bottom hose, leaving it plugged and draining it every now and then when the level in the hose goes up.
In theory, this should be more efficient than your standard solar still. In practice... well, has anyone tried something like this? Or do I have to go out and tinker?
Say you have a bore/well with bad water in it. You get some water out of it and want to purify it. Now, a 20 or 30 foot column of water will lower the pressure enough that the water at the top of that column will boil at 50 or 60 degrees C or so.
If you :
- take an enclosed container/still full of dirty water, painted black in the sun.
- put a tap at the top, run a hose (coiled and cooled/shaded) into another sealed container.
- put a tap at the bottom of the container with a hose attached.
- drop the hose back down the bore to the water level.
- open the taps.
You'll end up with a partial vacuum in the top of the still, dependant on how deep your bore is. With that partial vacuum, you lower the boiling point / increase the evaporation rate of the water. So after you get the initial vacuum, you turn off the bottom tap for a while. You might be able to leave the bottom tap open in use, I dunno.
So you end up with vapour in the top of the still which will (er, should) condense out the cooler top pipe into your container. Vapour will still head towards the container, as it's sealed, and the same partial vacuum as the rest of it. When you want the clean water, you turn off the taps and take the clean container off.
The same sort of thing without the well could be done by hoisting the still up into a tree, or post. In that case, you might even be able to get away with just running the top hose back down to below the level of the bottom hose, leaving it plugged and draining it every now and then when the level in the hose goes up.
In theory, this should be more efficient than your standard solar still. In practice... well, has anyone tried something like this? Or do I have to go out and tinker?