Improved ambient water condenser system

Abstract

An ambient water condenser system is disclosed having a condensation chamber that at least partially contains or surrounds a fluid reservoir that contains a volume or mass of a hygroscopic aqueous solution for condensing water from ambient air, and a distillation process for extracting water from the solution. The fluid reservoir has a heat source, a lower porous hydrophobic membrane, and an upper porous hydrophobic membrane. The heat source causes the hygroscopic solution near the top of the reservoir to have a higher temperature, which causes it to have a higher water vapor pressure, whereby the water vapor that passes through the upper porous hydrophobic membrane and enters the condensation chamber condenses into liquid water.

Description

[0001] Related Applications

[0002] Applicants claim the benefit of U.S. Provisional Application No. 62 / 829,077, filed on April 4, 2019, entitled “Ambient Water Condenser,” pursuant to 35 U.S.C. §119(e), which is incorporated herein by reference. Technical Field

[0003] The present invention generally relates to an improved ambient water condenser apparatus, system and method. More particularly, the present invention relates to an improved ambient water condenser apparatus, assembly, method and system having components configured to provide potable water extracted from ambient air. Background Art

[0004] Although approximately 71% of the Earth's surface is water, more than 95% of it is in the oceans and seas, which are not drinkable. The remaining approximately 15% of the Earth's water is in rivers, lakes, ice sheets, glaciers, groundwater, aquifers, and water vapor. As the Earth's population exceeds 7 billion people, there is an increasing need to provide a source of fresh drinking water, especially in arid climates and underdeveloped regions where water resources are scarce.

[0005] Devices that extract water from the surrounding atmosphere would be useful in many applications. Applications range from supplying drinking water in geographic locations where fresh water is scarce to home use applications, such as a practical device for keeping home flower plants watered. For example, it is more practical to make an electrical connection to the flower plants in a building where distributed power sources are generally available. In this application, there is no need to connect water lines to the flower plants, only an electrical connection is required. The device uses thermal energy to drive the extraction process. Depending on the application, heat can be provided from a range of sources. For example, for large-scale production of drinking water in arid climates, solar energy would be an attractive heat source. On the other hand, for smaller-scale applications, such as water production in building dehumidification, electrical power may be optimal.

[0006] Atmospheric moisture generators utilizing water condensation systems are commonly used to extract water from the surrounding atmosphere. However, many such systems are expensive, requiring bulky, inefficient components that operate in large water condensation systems. Other solutions for creating drinking water include water desalination systems and mist collectors. However, many of these solutions are quite cumbersome, inefficient, and expensive.

[0007] Therefore, there remains a need for improved, efficient, inexpensive atmospheric moisture extraction systems. Devices that extract water from the ambient atmosphere are useful in many applications, such as supplying drinking water in geographic locations where fresh water is scarce and keeping household plants watered. Various aspects of the present invention satisfy this need and other needs. Summary of the invention

[0008] An improved ambient water condenser is provided. In accordance with the purposes of the present invention, as presented and described herein, in one aspect, the present invention relates to an improved ambient water condenser system, such as an apparatus for extracting water from ambient atmosphere. In a further aspect, an improved ambient water condenser apparatus, system and method are provided to supply drinking water in geographical locations where fresh water is scarce. The present invention relates to a hygroscopic solution for condensing water from ambient air and a distillation process for extracting water from said hygroscopic solution, wherein said hygroscopic solution is a desiccant.

[0009] The ambient water condenser comprises a hygroscopic solution reservoir containing a hygroscopic aqueous solution; at least one porous hydrophobic membrane configured so that the hygroscopic aqueous solution does not pass through the pores of the membrane, while a gas (e.g., water vapor) freely permeates the porous hydrophobic membrane; a condensation chamber configured to convert water vapor into liquid water via a condensation process; a dropper configured to receive condensed water flowing out of the condensation chamber; a heat collector; a heat transfer member, wherein the heat collector can be thermally coupled to the interior of the hygroscopic solution reservoir; and a heat source. In a further aspect, the hygroscopic solution reservoir has an inlet and an outlet, wherein the hygroscopic solution can be contained in the hygroscopic solution reservoir. The inlet of the hygroscopic solution reservoir can be coupled to the external ambient air via a first porous hydrophobic membrane. The hygroscopic solution can absorb moisture from the external ambient air at the inlet of the hygroscopic solution reservoir. The outlet of the hygroscopic solution reservoir is coupled to the interior of the condensation chamber, and can include a second porous hydrophobic membrane coupling the outlet of the reservoir to the condensation chamber. A heat source may be coupled to the hygroscopic solution at the outlet of the hygroscopic solution reservoir to heat the solution and evaporate water therefrom. The condensation chamber may be thermally coupled to the external ambient air to limit its temperature rise, thereby promoting condensation of water evaporated from the hygroscopic absorber at the outlet of the solution reservoir. The absorption rate may be such that the hygroscopic solution at the inlet may maintain a water partial pressure close to equilibrium with the external ambient air. In operation, the device absorbs moisture from the ambient air at the inlet and evaporates the absorbed water into the condensation chamber, where it is condensed into a liquid and released for external use.

[0010] The present invention provides an atmospheric moisture extractor with a variety of applications. For example, in one or more aspects, the present invention can facilitate large-scale production of drinking water in arid climates. In this and other cases, solar energy can be the primary heat source. In other cases, the power source can be the best power source for producing water in smaller scale applications such as watering domestic flowers and plants or dehumidifying buildings. The device can use thermal energy to drive the water extraction process. In one or more instances, depending on the application, heat can be provided from a range of sources including solar energy, thermal energy, power stations, electric current and other devices.

[0011] In still a further aspect, the improved ambient water condenser apparatus further comprises a heat source operative to increase the temperature of the hygroscopic solution proximate the outlet of the hygroscopic reservoir to evaporate water from the hygroscopic solution, wherein the evaporated water is subsequently condensed in the condensation chamber.

[0012] In yet a further aspect; the present invention further comprises a hydrophobic membrane for containing a hygroscopic solution while providing passage of water vapor into and out of the hygroscopic solution.

[0013] Other aspects, objects, features and advantages of the present invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a perspective view of a preferred form of an ambient water condenser system of the present invention.

[0015] Figure 2 is a perspective view of another preferred form of an ambient water condenser system of the present invention.

[0016] Figure 3 is a perspective view of another preferred form of an ambient water condenser system of the present invention.

[0017] Figure 4 is a perspective view of an ambient water condenser system in yet another preferred form of the present invention. DETAILED DESCRIPTION

[0018] Referring now to the accompanying drawings, there is shown an ambient water condenser system 1 of a preferred form of the present invention. The ambient water condenser system may also be referred to as an atmospheric moisture extraction device. The condenser system 1 comprises a condensation chamber 10 having an outer wall 10' which at least partially contains or surrounds a fluid reservoir 2. The condensation chamber 10 has a lower end coupled to a drip tube 12 and in fluid communication with the drip tube.

[0019] The condensation system 1 also has an infrared transparent cover 14, which together with the condensation chamber 10 forms a heating chamber, and a heat collection surface or collector 16, which is below the cover 14 and within the heating chamber. The collector 16 is coupled in thermal communication with a heat transfer member 17, which extends through the top end of the condensation chamber 10 and into the reservoir 2. The heat transfer member 17 is a heat conductive material, such as copper or aluminum, or it can be a heat pipe or other heat transfer device.

[0020] The fluid reservoir 2 contains a volume or mass of a hygroscopic aqueous solution 8 for condensing water from the surrounding air, and a distillation process for extracting water from the solution. The fluid reservoir 2 comprises a lower porous hydrophobic membrane 4 and an upper porous hydrophobic membrane 6. The properties of the hydrophobic porous membranes 4 and 6 are such that the hygroscopic solution 8, which is an aqueous liquid, does not wet or pass through the pores of the membranes; however, gases such as water pass freely in their vapor phase, while liquid water is prevented from passing through. The lower porous membrane 4 connects the reservoir 2 to the external surrounding air (water vapor source). The hygroscopic solution 8 at the reservoir inlet or lower end proximity exchanges moisture with the source through the lower membrane 4 so as to approach water vapor pressure equilibrium with it. The upper porous membrane 6 connects the reservoir 2 to the interior of the condensation chamber 10.

[0021] The infrared transparent cover 14 and the collector 16 are used to radiate heat, such as solar energy. The cover 14 encloses the collector 16 to prevent the heat collected by 16 from being lost to the surrounding air via convection heat transfer. In this way, the collector 16 and the heat transfer member 17 can be maintained at an elevated temperature by heat 18 collected from an external source. Operation is such that the heat 18 (Q) captured by the collector 16 is transferred to the hygroscopic solution 8 through the heat transfer member 17, as shown by arrows 21.

[0022] The higher temperature of the hygroscopic solution 8 near the top of the reservoir 2 causes it to have a higher water vapor pressure. Water vapor evaporates from the hygroscopic solution 8 and leaves the reservoir 2 through the upper porous hydrophobic membrane 6, as shown by arrow 11. The wall of the chamber 10 is thermally coupled to the surrounding air and is maintained at a lower temperature than the hygroscopic solution 8 near the top of the reservoir 2. Water vapor leaves the reservoir 2 through the upper porous hydrophobic membrane 6 at a higher temperature and partial pressure than water outside the condensation chamber 10. In this way, the water vapor leaving the reservoir 2 condenses onto the inner surface of the condensation chamber 10 while transferring the condensation heat to the inner surface of the condensation chamber 10, as shown by arrow 20. The condensation heat 20 is in turn coupled to the external surrounding air. The resulting condensed water flows out of the condensation chamber 10 through the dropper 12.

[0023] The density of the hygroscopic solution 8 increases as the water it contains evaporates. The natural tendency is for the high density solution to drift toward the bottom of the reservoir 2 and displace the lower density, higher water content hygroscopic solution. The displaced low density hygroscopic solution rises to the top of the reservoir where it is heated, causing it to release the absorbed water. The hygroscopic solution 8 flowing from the top to the bottom of the reservoir 2 cools and subsequently absorbs water to reach thermodynamic equilibrium with the temperature and water vapor partial pressure of the surrounding air, to which the bottom of the reservoir 2 is thermally coupled. As it cools, its water vapor pressure decreases to a level below that of the external ambient air, which causes it to absorb water vapor from the atmosphere through the hydrophobic membrane 4. Thus, the replenishing solution continuously drifts upward due to its lower density, and as the water is depleted, the higher density solution continuously drifts downward, thereby forming a continuous circulating flow. The operation causes water to be continuously extracted from the surrounding air and supplied to the drip tube 12, which in turn empties the water into the holding container 40, as shown in FIG. Figure 2 As displayed.

[0024] Figure 2 An alternative embodiment of the invention is shown in which the hygroscopic fluid 8 is heated near the top of the reservoir 2 by applying power to the heater 24. Figure 2 An optional second heater 30 is added. The optional heater 30 increases the bulk temperature of the hygroscopic fluid, thereby inhibiting atmospheric moisture absorption by raising its temperature and thus the water vapor pressure. It protects the device in very high humidity conditions, where the hygroscopic solution would otherwise absorb more water than is needed, or more than can be accommodated in the reservoir 2.

[0025] Figure 3 An embodiment of the present invention is shown which includes a clearance chamber 34 for accommodating changes in the equilibrium state of the total water content of the hygroscopic solution 8. The excess volume 36 allows the solution 8 to expand and contract as needed due to its average water content varying with the surrounding humidity conditions. Under high humidity conditions, as the solution 8 absorbs water from the surroundings through the membrane 4a, its volume expands to a point where the water vapor pressure of the solution 8 in the lower portion of the reservoir 2 equals the water vapor partial pressure of the surrounding air. Conversely, under low humidity conditions, the solution 8 contacts as water evaporates therefrom until the solution 8 in the lower portion of the reservoir 2 reaches a water vapor pressure equal to the water vapor partial pressure of the surrounding air. The clearance chamber 34 protects the device under very high humidity conditions where the hygroscopic solution absorbs more water than can be contained within the reservoir 2. The clearance chamber 34 maintains the solution at the inlet and outlet of the reservoir 2 even though the actual volume of the solution may vary.

[0026] In addition, this embodiment demonstrates the use of a single diffusion membrane 4a extending downward from the top of the reservoir 2 within the condensation chamber 10 to the bottom of the reservoir 2 exposed to the ambient air. The hygroscopic fluid 8 is heated near the top of the reservoir 2 by applying power to the heater 24. The heat supplied near the top of the reservoir 2 causes the vapor pressure of the water in the solution to rise to a level that causes it to evaporate from the solution and leave the reservoir 2 by diffusion through the top area of ​​the membrane 4, as shown by arrow 11. When the chamber 10 is thermally coupled to the surrounding ambient air, the walls of the chamber 10 are maintained at a temperature lower than the hygroscopic solution heated in the reservoir 2. The water vapor leaves the reservoir 2 through the membrane 4a in a superheated state, temperature, and partial pressure relative to the lower temperature and vapor pressure on the walls of the condensation chamber 10. In this way, the water vapor diffuses through the portion of the membrane 4a extending into the chamber 10, condensing onto the inner wall of the condensation chamber 10 as it transfers the condensation heat 20 to the condensation chamber 10. The condensation heat 20 is then coupled to the external ambient air. The generated condensed water flows out of the condensation chamber 10 through the drip tube 12 .

[0027] The density of the hygroscopic solution 8 increases as the water it contains evaporates. The natural tendency is for the high density solution to drift toward the bottom of the reservoir 2. In doing so, it displaces the lower density, higher water content solution. The displaced low density solution rises to the top of the reservoir, where it is heated, causing it to release the absorbed water. The concentrated solution at the bottom of the reservoir 2 cools due to heat transfer to the surrounding air. As it cools, its water vapor pressure decreases to a level below the water vapor partial pressure of the external ambient air, which causes the solution 8 to absorb atmospheric water vapor 22 through the portion of the membrane 4a exposed to the ambient air. Thus, the solution replenished with water continuously drifts upward due to its lower density, and when the water is exhausted, the higher density solution continuously drifts downward, cooling the absorbed ambient water. The operation causes water to be continuously extracted from the ambient air and supplied to the drip tube 12. An alternative heat source, such as solar energy or other suitable heat source, may be used in place of the heater 24.

[0028] Figure 4An alternative configuration utilizing convection circulation to promote more efficient operation of an atmospheric moisture condenser is shown. The hygroscopic solution reservoir 2a is configured as a flow loop, which is composed of a heated substantially vertical column 55 and a cooled substantially vertical column 57, wherein the heated substantially vertical column 55 is heated by a heat source 24a, and the cooled substantially vertical column 57 dissipates heat 30a to the external environment. When heat is supplied to the column 55 and removed from the column 57, the hygroscopic solution 8 circulates in the reservoir 2a under natural convection flow, as shown by arrows 59. The more concentrated, cooled, dehydrated, low water vapor pressure hygroscopic solution 8 leaves the column 57 and circulates through the membrane 4. When passing through the porous hydrophobic membrane 4, it absorbs atmospheric moisture 22. The solution 8 then enters the vertical column 55, where it is heated, causing water vapor 51 to evaporate from the solution. In this example, the condensation chamber 10a is configured as a flow loop that shares a common conduit 58 with the reservoir 2a. Heating solution 8 in column 55 causes water vapor 51 to evaporate from solution and rise to substantially vertical column 56, wherein dewatered solution 8 enters conduit 58. Gas contained in condensation chamber 10a circulates under natural convection force, as shown in arrows 53 and 63. Said circulation is driven by water vapor 51 of heating that flows upward in column 56, and then is cooled when it flows downward in section 54. When gas cools in part 54 of condensation chamber 10a, water vapor condenses as mixture flows downward. Section 54 is thermally coupled to surrounding environment, thereby condensation heat 20 is discharged. As shown in the figure, the condensed water obtained is collected by pipe 12a.

[0029] It can thus be seen that there is now provided an ambient water condenser system which is more efficient and simpler in form. Although the invention has been described in detail with particular reference to preferred embodiments thereof, it will be appreciated that numerous modifications, additions and deletions other than those explicitly described may be made thereto without departing from the spirit and scope of the invention as hereinbefore described in the appended claims.

Claims

1. An ambient water condenser system, comprising: One volume of hygroscopic solution; a fluid reservoir containing the volume of the hygroscopic solution, the fluid reservoir having an outlet, an inlet in fluid communication with ambient air, and a first air-permeable hydrophobic membrane mounted at the inlet, the first air-permeable hydrophobic membrane having a first side exposed to the ambient air and a second side disposed opposite to the first side and exposed to the hygroscopic solution, the first air-permeable hydrophobic membrane allowing water vapor from the ambient air to pass therethrough and reach the hygroscopic solution and preventing liquid water from passing therethrough, and a second air-permeable hydrophobic membrane mounted at the outlet allowing water vapor from the hygroscopic solution to pass therethrough and preventing liquid water from the hygroscopic solution from passing therethrough; a heat source in thermal communication with the hygroscopic solution within the fluid reservoir; a condensation chamber in fluid communication with the fluid reservoir through the outlet and the second gas-permeable and hydrophobic membrane; Thereby, the hygroscopic solution near the inlet of the reservoir absorbs water vapor, and the heat source operates to increase the temperature of the hygroscopic solution to raise its vapor pressure so as to release the water vapor into the condensation chamber where it then condenses.

2. The ambient water condenser system of claim 1, further comprising a second porous hydrophobic membrane positioned to allow water vapor to pass through the outlet and prevent liquid water from passing through the outlet.

3. The ambient water condenser system of claim 1, wherein the heat source is positioned to heat the hygroscopic solution adjacent the outlet and away from the inlet.

4. The ambient water condenser system of claim 1, wherein the heat source is a solar thermal source.

5. The ambient water condenser system of claim 1, wherein the heat source is an electrical resistance heat source.

6. The ambient water condenser system of claim 1, wherein the condensing chamber is thermally coupled to a water source to maintain a temperature below the temperature of the hygroscopic solution adjacent the reservoir outlet.

7. The ambient water condenser system of claim 1, further comprising a clearance container in fluid communication with the reservoir.

8. The ambient water condenser system of claim 1, further comprising a drip tube coupled to the condensing chamber.

9. The ambient water condenser system of claim 8, further comprising a water holding container coupled to the drip tube.

10. An atmospheric moisture extraction device, comprising: a hygroscopic solution reservoir having a water vapor inlet located at a lower portion of the hygroscopic solution reservoir and an outlet located at an upper portion of the hygroscopic solution reservoir; a hygroscopic solution contained within the reservoir; a condensation chamber in fluid communication with the hygroscopic solution reservoir; and a heat source in thermal communication with the hygroscopic solution; The water vapor inlet of the reservoir is in fluid communication with external ambient air, The outlet of the reservoir is in fluid communication with the interior of the condensation chamber, a breathable hydrophobic membrane installed in the water vapor inlet and the outlet, and The hygroscopic solution reservoir and the breathable hydrophobic membrane prevent the hygroscopic liquid from directly contacting the external ambient air, Thereby, moisture from the ambient air is absorbed by the hygroscopic solution at the water vapor inlet of the reservoir so that the hygroscopic solution maintains a moisture partial pressure close to equilibrium with the ambient air, and the heat source operates to increase the temperature of the hygroscopic solution near the outlet of the reservoir, the moisture evaporates from the solution, and the evaporated moisture condenses in the condensation chamber.

11. The atmospheric moisture extraction device of claim 10, wherein the air-permeable hydrophobic membrane comprises a first air-permeable hydrophobic membrane mounted to the water vapor inlet.

12. The atmospheric moisture extraction device of claim 11, wherein the air-permeable and hydrophobic membrane further comprises a second air-permeable and hydrophobic membrane mounted to the outlet.

13. The atmospheric moisture extraction device of claim 10, further comprising a clearance container in fluid communication with the reservoir.

14. A device for extracting moisture from ambient atmosphere, the device comprising: a hygroscopic solution reservoir having an inlet and an outlet; a hygroscopic solution contained in the hygroscopic solution reservoir; a first hydrophobic moisture vapor permeable membrane; Condensation chamber, and Heat source, The first hydrophobic moisture vapor permeable membrane covers the inlet of the reservoir and connects the solution therein to the surrounding atmospheric air, The outlet of the reservoir is coupled to the interior of the condensation chamber, The heat source is thermally coupled to the hygroscopic solution, The condensation chamber is thermally coupled to the surrounding air, Thus, diffusion of ambient air moisture through the first hydrophobic moisture vapor permeable membrane causes the hygroscopic solution near the inlet of the reservoir to maintain a partial pressure close to equilibrium with the ambient atmospheric water vapor, and the heat source operates to increase the temperature of the solution near the outlet of the reservoir so as to raise the partial pressure of moisture therein, thereby causing it to evaporate from the solution into the condensation chamber and condense at a temperature close to the ambient temperature of the condensation chamber.

15. The atmospheric moisture extraction device according to claim 14, further comprising a second moisture permeable membrane installed at the outlet of the reservoir and connecting the outlet of the reservoir to the interior of the condensation chamber, Thus, water evaporated from the solution enters the condensation chamber by passing through the second moisture permeable membrane.

16. The atmospheric moisture extraction device of claim 14, wherein the first hydrophobic moisture vapor permeable membrane is a porous hydrophobic material.

17. The atmospheric moisture extraction device of claim 15, wherein the second moisture permeable membrane is a porous hydrophobic material.

18. The atmospheric moisture extraction device of claim 14, further comprising a drip tube connected to the condensation chamber.

19. The atmospheric moisture extraction device of claim 14, further comprising a clearance chamber for accommodating changes in the equilibrium state of the total water content of the hygroscopic solution, Thus, as the average water content of the interstitial chamber varies with the surrounding humidity, it allows the solution to expand and contract as needed.

20. The atmospheric moisture extraction device of claim 14, wherein the first hydrophobic moisture vapor permeable membrane couples the reservoir to the condensation chamber and the surrounding air, whereby water vapor passes from the surrounding air through the first hydrophobic moisture vapor permeable membrane into the hygroscopic solution and evaporates from the hygroscopic solution through the first hydrophobic moisture vapor permeable membrane into the condensation chamber.

Images