Production Of water from atmospheric air

Extracting Pure water From Atmospheric Humidity

Pure water, not only pure but usable surface water is going to be, or is a big threat to the existing living system on earth. That is the reason now we are spending considerable amount of time and money to find an alternate planet with water and other livable conditions. The scenario may different like, we can migrate to new space or we can transport water from there to our reservoirs. But my gut feeling is, we have spent more time to think, how we can reduce the use of water, how we can avoid wastage of water, and more importantly how we can produce water.



Production of water from air humidity

 

Production of water from atmospheric air

This is a very hot topic to discuss and a lot of research and investment is going on this topic. Even in hot and dry area, there is a lot of moisture available in air. And due to increasing in global warming, the moisture content in the air is going to more in future and surface and ground water availability will go down.

This idea will succeed only if the production cost is nominal and the technology is simple and affordable. In future our main target is developing a renewable source of water and fuel production.

There are mainly two process involve in water production from atmospheric air.

1.    Absorption of humidity from air

2.    Separation and condensation (desorption)

 

Absorption of water from atmospheric air

 


Absorption of atmospheric humidity

In order to make the absorption of the air humidity in the saline solution as efficient as possible, a large interface with the air and a long contact time are necessary. This is done by allowing the saline solution to flow slowly down sorption strings in tower-shaped, naturally ventilated plant modules and to absorb the water from the air. By means of a special design of the sorption strings an efficient mass transfer is achieved and the saline solution is diluted by the substantial absorption of water.

Desorption : distillation and condensation

The water has to be separated from the circulating saline solution (desorbed), and so a distillation process follows. The distillation is effected by means of gravity-assisted, multiple-stage vacuum evaporation. To do this, the saline solution, diluted with water, is subjected to a vacuum, which considerably reduces the evaporation temperatures. The advantage of this is that these temperatures can be achieved with simple solar thermal collectors or also with waste heat. Since the plant works with a negative pressure, it is also possible to use the thermal energy employed several times in various evaporation stages with different pressures. The water vapor produced in the distillation is condensed and can be used as high-quality drinking water.

A combined tower-construction for the sorption and desorption makes it possible to use the gravity of the process flows to create the required vacuum. Energy-intensive vacuum pumps are no longer needed.

This is an exaple of pracal application of the technology Biilsboard that produce water in Peru.