Here’s an idea I had:

Consider how a rocket stove works..

There is an inlet where wood is fed into the stove and an outlet for which the exhaust can vent. Very simple but very effective.

Now apply that idea toward a water collection device:

Instead of using fire and wood use a heating element or alternatively you could use a fresnel lense heating a metal surface with focused concentrated sunlight.

The hot air would rise out the outlet of the stove and I believe this would draw in air into the inlet of the stove. Not sure whether a constriction at the top of the outlet would be ideal to create a pressurized release of heated air that may draw in even more air into the inlet or whether that would lessen the ability.

Zeolite rocks could be placed into where the wood would normally be stacked such that the air would be drawn through the porous material. This would cause the water to bead up and accumulate. You could make a drip pan to divert the water off into a container at that point.

So my question is:

With wood burning stoves and rocket stoves, there is a lot of air drawn into the stove and often in a lot of airflow (several CFM.)

Is this condition possible to recreate absent consumables? Could just heating the air make this possible? I know that smoke and the various release of different hydrocarbons have more mass then air alone so that would create more of a draft. Also when fire burns it consumes the oxygen in the air.

The ideal condition is to have a high rate of airflow going through the device so that water in the air will accumulate in the zeolite and be harvested. With heating air alone in the above described arrangement (absent consumables) is this possible to create a high rate of airflow?


1 Answer 1


Dry zeolite will absorb water vapour, as indeed will many solids. However once the zeolite is saturated with water it will stop absorbing any further water. Water will not condense on the zeolite and drip off.

There is nothing wrong with the principle of pumping air through some mechanism for collecting water. This is basically what happens with fog collection systems used for example in South America. But these only work because the air becomes supersaturated in water vapour when the temperature falls in the early morning. In your case the air will be sub-saturated with water and the water cannot be collected this way. Your mechanism isn't going to work without some way of cooling the incoming air to below the dew point.


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