I might be too stupid to understand why the described thing below not should work.
I´m sure there is someone that can give it thumbs up or down.
Before reading the thing below it might be a good thing reading the thread started by Anjou : Water
water everywhere around , the thread inspired me into a lot of thinking in if we can get our freshwatersupply in a new way.
Let´s start with the general idea. Water
heated by the sun boiling of stem that is condensed back to pure water.
I started in looking at what lowpressure is possible to get using a very low cost pump such as a reversed tire pump for your bike or a tirepump 12V for your car or why not a danfoss compressor
from the refrigerator
not working any more..
I got the result that the lowpressure achivable will make water boil in the 50-60 degrees celcius range! A lot better than I first thought .
I belive this temperature is very easy to achive with sun energy!
Getting the lowpressure ( Vacuum) is easy but you shuld not really have to be pumping all day to keep the low pressure as the water boils away so this little problem needed solving.
I belive this is fairly easy on a Sailing boat with a 12 Meter + high mast
What I´m thinking of is using a thin tube high up connected to a coarse tube ( some 15 cm diameter) down below with a watertight piston within that is free to move upwards but can not fall out in the bottom.
You would start by filling this tower with potable water some 9 meters high. Next you pump out untill reaching your low pressure of aprox - 26 inches mercury
and this way you will be lifting the watercolumn that will keep the lowpressure in the system with its own weight.
How will it work ones the water starts to boil?
The vapour will go in a tube from the "sun boiler" to the top of the fine tube in the mast
. As this happens the watercollumn will start to sink keeping the low pressure. Vapour is around 16000 times bigger when it comes to volume than water. This fact works both ways and it will contract
just as much ones it is cooled back to water in the column.
The thing will have to be restarted ones you have produced enough fresh water and the movable piston hits the lower restriction.
At this point you tap of the produced water and start all over again.
To Easy to work??