Development of Atmospheric Water Harvesting

Project Title

Development of Atmospheric Water Harvesting

Project Area of Specialization Mechanical EngineeringProject Summary

The increasing of the world population without increasing the natural resources caused water shortage in many regions around the world. Herein is a review of a new freshwater resource depending on harvesting the moisture of the atmospheric air. There are two main methods for extracting water from the ambient air: including composite materials method and cooling the air to the dew point. In the first method, the composite materials absorb the atmospheric air’s moisture and regenerate it into drinking water under certain conditions. The second method requires just cooling of the atmospheric air until its moisture gets condensed. Power sources based on renewable energy have been developed to drive various techniques, such as vapor compression cycles, absorption cycles, and Peltier effect-based devices. Therefore, researchers have come out with new methods for freshwater production as a starting to get rid of the water and energy crises. There is a good and available source of water, which is the moisture in the air, and there is a fact that water can be extracted from air by approximately 1000 m3/day. In addition, it is a high-quality renewable source of water production. The absorption–regeneration technique depends on extracting water from the air by means absorbent materials at night; then the water is extracted by evaporation and condensation at the day. The diurnal extraction process is conducted using solar energy that leads to evaporation of the absorbed water, which is condensed at the cover to be collected. Poly diallyl dimethyl ammonium chloride G-PDDA absorbed moisture from the air at night and the heat generated by the absorption process transferred to a thermoelectric module to generate electricity. Then, G-PDDA was exposed to the sunlight to raise the temperature of the composite material (G-PDDA) and the absorbed water starts to evaporate and condense on a cold cover to be collected in a container as water drops. On the other hand, the residual heat from regeneration process transferred to the thermoelectric module to generate electricity. The best results of this experiment were that it made one complete cycle in 22 min, during the moisture capture process at a relative humidity of 60%, 6.6 mW/m2 and during the water release process, the model device could achieve an output power density of 520 mW/m2 under 1 kW/m2 solar irradiation.

Project Objectives

Extracting water from the ambient air particularly for arid areas with a excess of water and Solar energy.

Project Implementation Method

First, various composite materials are used to absorb the moisture from the air at night; then, the absorbed moisture is extracted by the processes of evaporation and condensation during the day.
Although these methods are very proper for wet areas, they cannot be effectively used in dry areas. Hence, other methods have been developed to produce water in areas with low humidity. The second method requires just cooling of the atmospheric air until its moisture gets condensed. Power sources based on renewable energy have been developed to drive various techniques, such as vapor compression cycles, absorption cycles, and Peltier effect-based devices. Therefore, researchers have come out with new methods for freshwater production as a starting to get rid of the water and energy crises. There is a good and available source of water, which is the moisture in the air, and there is a fact that water can be extracted from air by approximately 1000 m3/day. In addition, it is a high-quality renewable source of water production. The absorption–regeneration technique depends on extracting water from the air by means absorbent materials at night; then the water is extracted by evaporation and condensation at the day. The diurnal extraction process is conducted using solar energy that leads to evaporation of the absorbed water, which is condensed at the cover to be collected.

Different AWH technologies are used for water harvesting; each has its advantages and disadvantages. The standard technique is the active refrigeration AWH technologies, which usually utilize a vapor compression cycle that consumes high-grade energy sources in the form of electricity to reduce the humid air temperature below its dew point to condense its water vapor content. The main disadvantages of these technologies are their energy-intensive nature and unfeasibility for low relative humidity and low-temperature regions. Another AWH technology that attracted researchers and companies in the last few decades is the sorption-based AWH. This technology uses sorption materials, such as the stated aforementioned materials, to collect and adsorb water vapor from humid air. To attain freshwater from adsorption materials, thermal energy is used to raise the temperature of the material to start the desorption process and release the adsorbed water that can be condensed and collected then. The main advantages of the sorption based AWH technologies are their ability to operate in a low relative humidity environment and be powered by solar energy, which helps reduce the operation cost and makes it environmentally friendly.

Benefits of the Project

Recently, the shortage of freshwater has become a serious world challenge the main aim to provide water in the desert areas.

1. It is cost-effective.
2. Harvest the water from atmosphere for use of Cholistan area.
3. A source of water for drinking purpose and landscape irrigation.
4. It is a simple method and easy to practice.
5. It reduces soil erosion and pollution of water bodies due to fertilizers and pesticides.

Technical Details of Final Deliverable

There are two main methods for extracting water from the ambient air: including composite materials method and cooling the air to the dew point. In the first method, the composite materials absorb the atmospheric air’s moisture and regenerate it into drinking water under certain conditions. The second method requires just cooling of the atmospheric air until its moisture gets condensed. Power sources based on renewable energy have been developed to drive various techniques, such as vapor compression cycles, absorption cycles, and Peltier effect-based devices. The absorption–regeneration technique depends on extracting water from the air by means absorbent materials at night; then the water is extracted by evaporation and condensation at the day. The diurnal extraction process is conducted using solar energy that leads to evaporation of the absorbed water, which is condensed at the cover to be collected. Different AWH technologies are used for water harvesting; each has its advantages and disadvantages. The standard technique is the active refrigeration AWH technologies, which usually utilize a vapor compression cycle that consumes high-grade energy sources in the form of electricity to reduce the humid air temperature below its dew point to condense its water vapor content. The main disadvantages of these technologies are their energy-intensive nature and unfeasibility for low relative humidity and low-temperature regions. Another AWH technology that attracted researchers and companies in the last few decades is the sorption-based AWH. This technology uses sorption materials, such as the stated aforementioned materials, to collect and adsorb water vapor from humid air. To attain freshwater from adsorption materials, thermal energy is used to raise the temperature of the material to start the desorption process and release the adsorbed water that can be condensed and collected then. The main advantages of the sorption based AWH technologies are their ability to operate in a low relative humidity environment and be powered by solar energy, which helps reduce the operation cost and makes it environmentally friendly.

Final Deliverable of the Project Hardware SystemCore Industry Energy Other Industries Health Core Technology Clean TechOther Technologies OthersSustainable Development Goals Clean Water and Sanitation, Affordable and Clean EnergyRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	79100
Desiccant Dehumidifier	Equipment	1	30000	30000
Refrigerant R600a	Equipment	1	12000	12000
Solar plates	Equipment	1	23000	23000
Acrylic sheet	Equipment	5	500	2500
Angle Iron	Equipment	8	200	1600
Visit to Cholistan Desert	Miscellaneous	4	1000	4000
Visit to Market in different cities	Miscellaneous	4	1000	4000
Visit to water purifier plant	Miscellaneous	2	1000	2000