Air-to-water generation system

Abstract

The present invention provides an air-to-water generation system comprising a water extraction unit for extracting water from an airflow. The water extraction unit comprises: an arrangement for implementing a refrigeration cycle, wherein the arrangement comprises a first evaporator and a second evaporator; a first water collection conduit, for collecting water from the first evaporator; and a second water collection conduit, for collecting water from the second evaporator. The system further comprises a storage tank for receiving and storing water from the first and second water collection conduits and a water treatment and dispensing unit. The water treatment and dispensing unit comprises: a dispensing unit, comprising a dispensing outlet controllable to dispense water responsive to input received via a user control interface, the dispensing outlet in fluid communication with the storage tank; and a controller operative to control operation of the dispensing unit.

Description

[0001] Air-to-water generation system

[0002] Technical Field

[0003] The present invention relates to an air-to-water generation system. In particular, but not exclusively, the present invention relates to an air-to-water generation system, comprising multiple evaporators and multiple collection points, and to a water extraction unit that forms part of the air-to-water generation system.

[0004] Background

[0005] The provision of water, particularly clean water, is essential in virtually every aspect of life. In regions of adequate rainfall and in developed regions which have access to piped water this is normally not a problem. However, many regions of the world have inadequate rainfall and are often great distances from water sources. In addition, the much-reported changes in global climate have further reduced rainfall in many regions, often in regions which already had inadequate rainfall.

[0006] The United Nations has predicted that by 2025, 1.8 billion people will face absolute water scarcity and two thirds of the world's population could be living under water-stressed conditions. It has also been estimated that 663 million people, roughly one in 10 of the world's population, lack access to safe drinking water.

[0007] Water from ground sources (e.g. reservoirs, aquifers, wells, etc.) comprise one source of potentially potable water for a population. However, the above issues have an impact on these limited sources of water.

[0008] Whilst water from ground sources is commonly bottled for distribution and sale to consumers, the bottles typically employed for containing the water are plastic bottles. There are currently concerns around the overuse of plastic in everyday life.

[0009] One way of supplying clean water in areas of water scarcity is by means of an air-to- water generator, sometimes known as an atmospheric water generator. Such generators can be used anywhere where the air has high humidity and a temperature consistently above 25° C. The water-containing air is passed over refrigerated coils, thereby condensing the water which can then be collected for later use.

[0010] Some types of air-to-water generation systems, or atmospheric water generation systems are configured to extract water vapour from air by condensation. Indeed, condensing systems are the most common technology in use. In such systems, a compressor is used to circulate refrigerant through a condenser coil and then an evaporator coil that cools the surrounding air. Once the air temperature reaches its dew point, water condenses into a collection tank. A fan is arranged to draw air into the system, which then passes over the evaporator coil.

[0011] The evaporator coil has a fixed surface area available on which water from the air can condense. Once water droplets form on the evaporator coil, they run, under the influence of gravity, along the coil to a lower edge thereof, from which point they drop from the coil into a collection conduit. In this type of coil, i.e., where air flows in a vertical direction across / around the coil (from above the coil to below the coil), it will be appreciated that as air moves across / around the coil from an upstream end of the coil to a downstream end of the coil, it will encounter more and more droplets, which are progressing to the downstream end of the coil (under the influence of gravity). It will be appreciated that less surface area may be available for condensing toward the downstream end of the coil (or lower edge of the coil), compared with that of the upstream end of the coil (or upper edge of the coil), because the space is occupied with water droplets that are running toward the lower edge of the coil. It may be said that the “extraction efficiency” of the evaporator coil, i.e., the free surface area space available on which moisture from the air can condense, potentially decreases from the upstream end of the evaporator coil (or upper edge of the coil) to the downstream end of the coil (or lower edge of the coil).

[0012] The present invention has been devised with the foregoing in mind.

[0013] Summary

[0014] According to an aspect of the present invention, there is provided an air-to-water generation system comprising a water extraction unit for extracting water from an airflow. The water extraction unit comprises: an arrangement for implementing a refrigeration cycle, wherein the arrangement comprises a first evaporator and a second evaporator; a first water collection conduit, for collecting water from the first evaporator; and a second water collection conduit, for collecting water from the second evaporator. The system further comprises a storage tank for receiving and storing water from the first and second water collection conduits and a water treatment and dispensing unit. The water treatment and dispensing unit comprises: a dispensing unit, comprising a dispensing outlet controllable to dispense water responsive to input received via a user control interface, the dispensing outlet in fluid communication with the storage tank; and a controller operative to control operation of the dispensing unit.

[0015] The provision of an additional evaporator (i.e., second evaporator) potentially increases the water extraction efficiency of the water extraction unit, compared with a water extraction unity that employs a single evaporator. That is, water extraction efficiency for a pair of evaporators, with each evaporator having a water collection point, may increase over that of a single evaporator, which has the same length as the combined lengths of the pair of evaporators and which has a single water collection point.

[0016] Optionally, the system may further comprise a user control interface for receiving user input.

[0017] Optionally, the user interface may be operative, responsive to received user input, to control operation of a dispensing valve to dispense water from the dispensing outlet.

[0018] Optionally, the dispensing valve may operate to cause water to be dispensed from the dispensing outlet in direct response to input received via the user control interface.

[0019] Optionally, the user control interface may comprise a mechanical element.

[0020] Optionally, the mechanical element may comprise a tap, lever, handle and / or button. Optionally, the user control interface may comprise an electronic element.

[0021] Optionally, the electronic element may comprise a button, a display a touch-screen display, and / or a motion sensing element.

[0022] Optionally, the user interface may be operative to communicate a user input instruction to the controller.

[0023] Optionally, the controller, responsive to a received user input instruction, may be operative to control operation of a / the dispensing valve to dispense water from the dispensing outlet.

[0024] Optionally, the dispensing valve may operate to cause water to be dispensed from the dispensing outlet in response to a signal received from the controller, the signal output by the controller to the dispensing valve responsive to input received at the controller via the user control interface.

[0025] Optionally, the arrangement may further comprise a third evaporator, and wherein the water extraction unit may further comprise a third water collection conduit, for collecting water from the third evaporator.

[0026] The provision of a yet further evaporator (i.e., third evaporator) potentially increases the water extraction efficiency of the water extraction unit further still, compared with a water extraction unit that employs a single evaporator.

[0027] According to another aspect of the present invention, there is provided a water extraction unit for an air-to-water generation system, the water extraction unit for extracting water from an airflow. The water extraction unit comprises: an arrangement for implementing a refrigeration cycle, wherein the arrangement comprises a first evaporator and a second evaporator; a first water collection conduit, for collecting water from the first evaporator; anda second water collection conduit, for collecting water from the second evaporator.

[0028] Optionally, the arrangement may further comprise a third evaporator, and wherein the water extraction unit may further comprise a third water collection conduit, for collecting water from the third evaporator.

[0029] Brief Description of the Drawings

[0030] One or more embodiments of the present invention are described further hereinafter, by way of example only, with reference to the accompanying drawings in which:

[0031] Fig. 1 schematically illustrates an air-to-water (ATW) generation system according to one or more embodiments of the present invention; and

[0032] Fig. 2 schematically illustrates an ATW generation system according to an optional arrangement.

[0033] Detailed Description of the Invention

[0034] Fig. 1 illustrates an air-to-water (ATW) generation system 10 according to one or more embodiments. The ATW generation system 10 comprises an air-to-water (ATW) generator 12 and a water treatment and dispensing unit 14.

[0035] ATW generator 12 comprises a water extraction unit 13, which, in the embodiment illustrated in Fig. 1, comprises a cooling condensation type generator. ATW generator 12 operates in a manner where moist air is drawn into a conduit 16 of the ATW generator 12 via an inlet 18 to the conduit 16. Air is discharged from the conduit 16 through an outlet 20 at an opposite end of the conduit 16 to the inlet 18. An air flow induction system is configured to induce a flow of air into and through the conduit 16. Air flow induction system comprises fan 21, which operates to draw air into the conduit 16 via inlet 18, and to expel air from the conduit 16 via outlet 20.

[0036] The ATW generator 12 further comprises first and second evaporators 22a, 22b, a condenser 24, a compressor 26 and a throttle device 28. Together, these elements operate to perform a refrigeration cycle in which compressor 26 circulates a refrigerant through condenser 24, throttle device 28, second evaporator 22b and first evaporator 22a.

[0037] The condenser 24 connects with an upstream end (i.e., with respect to a direction of refrigerant circulation) of the second evaporator 22b via the throttle device 28. A downstream end of the second evaporator 22b connects with an upstream end of first evaporator 22a, and a downstream end of first evaporator 22a connects with an upstream end of compressor 26. When the refrigerant leaves the condenser 24 and enters the throttle device 28, pressure of the refrigerant drops due to the constriction in the refrigerant flow-path presented by the throttle device 28. This causes the temperature of the refrigerant fluid to decrease. The relatively cold refrigerant fluid that exits the throttle device 28 is then routed first to second evaporator 22b, then from there to the first evaporator 22a.

[0038] After exiting the first evaporator 22a, refrigerant fluid within the refrigeration cycle is compressed by the compressor 26 and is pumped to the condenser 24, at which point the cycle begins again.

[0039] Arrows in the figure indicate direction of refrigerant flow through the circuit that comprises the elements that operate to perform the refrigeration cycle.

[0040] Warm, moist air drawn into the conduit 16 by the fan 21 first passes over the first evaporator 22a, which absorbs energy from the air, reducing the temperature of the air and resulting in condensation of water from the air on the surfaces of the first evaporator 22a. This water extracted from the air on the first evaporator 22a is collected in a first collection conduit 29a, which is configured to direct collected water to a first water storage unit 30a (discussed further below).

[0041] Following passage of the air flow over the first evaporator 22a, the air flow then encounters the second evaporator 22b and passes thereover. As with the first evaporator 22a, when the air flow passes over the surfaces of the second evaporator 22b this will cause water in the air flow to condense on the surfaces of the second evaporator 22b. This water extracted from the air flow on the second evaporator 22b is collected in a second collection conduit 29b, which is configured to direct collected water to a second water storage unit 30b (discussed further below).

[0042] In the ATW generation system 10 illustrated in Fig. 1, the ATW generator 12 also comprises (optional) air filter 27, which is located in conduit 16 upstream of evaporator 22a. The air filter 27 serves to remove, or reduce, particulate matter in an air stream reaching the evaporator, and may be further configured to remove, or reduce air-borne pathogens in the air stream and / or treat air-borne pathogens in the air stream.

[0043] In the ATW generation system 10 illustrated in Fig. 1, the first and second water storage units 30a, 30b form part of water treatment and dispensing unit 14.

[0044] The water treatment and dispensing unit 14 illustrated in Fig. 1 further comprises: a water storage tank 31, which receives water collected in the first and second water storage units 30a, 30b via conduit 32; a first (optional) pathogen treatment device 33 operative to treat water stored in the water storage tank 31; a dispensing unit 34 controllable to dispense water; a pump 35 for inducing flow of water from the water storage tank 31 to the dispensing unit 34; a user control interface 36; a second (optional) pathogen treatment device 38 operative to treat water in the dispensing unit 34; and a controller 40 operative to control operation of at least the first pathogen treatment device 33 and the second pathogen treatment device 38. An optional water filtration system 42 may also form part of the water treatment and dispensing unit 14.

[0045] Water collected in the water storage tank 31 can be pumped via pump 35 and water filtration system 42 to dispensing unit 34. Water can be dispensed from the dispensing unit 34 through a dispensing outlet of the dispensing unit. Control of dispensing of water from the dispensing unit is by way of operating a valve 44.

[0046] Water received in the water storage tank 31 from the ATW generator 12 can be rendered potable (i.e. safe-to-drink) by a treatment process implemented by the water treatment and dispensing unit 14. Initially, first pathogen treatment device 33 is operated to treat water stored in the water storage tank 31. In one or more embodiments, the first pathogen treatment device 33 comprises an ultra-violet (UV) radiation source configured to irradiate water stored in the water storage tank 31 with UV light. UV light rays emitted by the first pathogen treatment device 33 can kill pathogens (e.g. protozoa, bacteria, etc.) in water within the water storage tank 31.

[0047] The water treatment process continues at the water filtration system 42, which can be configured to remove, or reduce particulate matter in the water stream. Following passage through the water filtration system 42, the water undergoes further treatment in dispensing unit 34. The second pathogen treatment device 38 is operated to treat water in the dispensing unit 34. In one or more embodiments, the second pathogen treatment device 38 comprises an ultraviolet (UV) radiation source configured to irradiate water in the dispensing unit 34 with UV light. UV light rays emitted by the second pathogen treatment device 38 can kill any remaining pathogens in water in the dispensing unit in proximity to the point of dispensing. In the illustrated embodiment, a portion 46 of a water conduit in the dispensing unit 34 is transparent to permit the irradiation of water within that portion of the water conduit with UV light rays emitted by second pathogen treatment device 38.

[0048] Treated water can be dispensed from a dispensing outlet of the dispensing unit 34 by controlling valve 44. Valve 44 is controlled by input received via user control interface 36. In one arrangement, user control interface 36 may comprise a mechanical control element (e.g. a tap) to operate the valve 44. In another arrangement, user control interface 36 may comprise an electronic control element. In a further arrangement, user control interface 36 may comprise a combination of both mechanical and electronic control elements. The user control interface 36 may also be configured to allow a user to input instructions to control operation of the water treatment and dispensing unit 14. Such instructions input by the user control interface 36 are conveyed to controller 40, which operates, responsive to the input instructions to control one or more elements of the water treatment and dispensing unit 14. In one example, the dispensing unit 34 operates to dispense water in response to a signal received from the controller 40, the signal output by the controller 40 to the dispensing unit 14 responsive to input received at the controller 40 via the user control interface 36.

[0049] The provision of an additional evaporator (i.e., second evaporator 22b) potentially increases the water extraction efficiency of the water extraction unit 13, compared with a water extraction unity that employs a single evaporator. That is, water extraction efficiency for a pair of evaporators 22a, 22b, with each evaporator having a water collection point (29a, 29b), may increase over that of a single evaporator, which has the same length as the combined lengths of the pair of evaporators 22a, 22b, and which has a single water collection point.

[0050] Fig. 2 illustrates an air-to-water (ATW) generation system according to an optional arrangement. In Fig. 2, features common to one or more other embodiments of the present invention, as described above, are denoted by like reference numerals.

[0051] The ATW generation system 10 illustrated in Fig. 2 differs from that illustrated in Fig. 1 in that the system 10 comprises an additional evaporator, i.e., third evaporator 22c. Additionally, the system 10 of Fig. 2 comprises another water storage unit, i.e., third water storage unit 30c, and an associated third collection conduit 29c (for collecting water from the third evaporator 22c and routing the collected water to the third water storage unit 30c).

[0052] After the air flow has passed over the first and second evaporators 22a, 22b, the air flow then passes over the third evaporator 22c, which again will result in condensation of water from the air on the surfaces of the third evaporator 22c. This water extracted from the air on the third evaporator 22c is collected in the third collection conduit 29c, which is configured to direct collected water to the third water storage unit 30c.

[0053] The provision of a yet further evaporator (i.e., third evaporator 22c) potentially increases the water extraction efficiency of the water extraction unit 13 further still, compared with a water extraction unit that employs a single evaporator.

[0054] In further optional arrangements, additional evaporators may be included.

[0055] In the above-described one or more embodiments, the water storage units 30a, 30b (30c) are described as forming part of water treatment and dispensing unit 14. However, in an optional arrangement, the water storage units 30a, 30b (30c) may form part of ATW generator 12, with the water storage units 30a, 30b (30c) of ATW generator 12 in fluid communication with water treatment and dispensing unit 14 (e.g. via a conduit to convey water from the ATW generator 12 to the water treatment and dispensing unit 14). In a further optional arrangement, the water storage units 30a, 30b (30c) may be separate from both the ATW generator 12 and the water treatment and dispensing unit 14.

[0056] In the above-described one or more embodiments, the ATW generation system 10 comprises a single fan in the ATW generator 12. However, in an optional arrangement, the ATW generator 12 may comprise two fans: one downstream of the evaporators 22a, 22b (22c), but upstream of condenser 24; and the other downstream of condenser 24. In another optional arrangement, the ATW generator 12 may comprise greater than two fans operative to draw air into the conduit via the air inlet and expel air therefrom via the air outlet. The one or more fans may comprise centrifugal and / or axial fans.

[0057] In the above-described one or more embodiments, the ATW generation system 10 is illustrated, in the accompanying figures, with a single air filter 27. However, in an optional arrangement, the air filter 27 may comprise a plurality of air filter units. The plurality of air filter units may be the same in some arrangements, and may be different in other arrangements (e.g. some may be to remove particulate matter and others may be to treat airborne pathogens). In some optional arrangements, at least one air filter may comprise a HEPA filter. In other optional arrangements, at least one air filter may comprise a filter that comprises a pathogen treatment agent (e.g. the filter may be chemically impregnated with an anti-bacterial agent).

[0058] In one or more embodiments, the ATW generator 12 may be located remote from the water treatment and dispensing unit 14. The ATW generator 12 and water treatment and dispensing unit 14 may be in fluid communication by way of a conduit connecting the two. In one or more embodiments, the water storage units 30a, 30b (30c) may be in the ATW generator side and in other one or more embodiments, the water storage units 30a, 30b (30c) may be in the water treatment and dispensing unit side. In further one or more embodiments, the water storage unit 28 may comprise a split unit, with one portion located in the ATW generator side and another portion located in the water treatment and dispensing unit side.

[0059] In one or more embodiments, an agitator, or stirrer, may be provided in a water storage unit and / or storage tank(s), or in multiple water storage units (in those embodiments having multiple units) to prevent water in the storage units / tanks from “standing” for too long.

[0060] In one or more embodiments, the ATW generation system 10 may be configured for communicative coupling to a communications network. Parameters and messages relating to the system operation (e.g. water generated, power consumed, cost per litre of water, fault messages, chiller / heater temperatures and control, filter change alert, water storage unit level, ambient temp, relative humidity, etc.) may be conveyed to a remote device via the communications network. This may allow an ATW generation system 10 to be monitored remotely. Optionally, the ATW generation system 10 could also be controlled remotely via the remote device in such an arrangement.

[0061] In one or more embodiments, water-containing elements of the system (e.g. water conduits and / or water storage units / tanks) may comprise an anti-pathogen agent. Optionally, the anti-pathogen agent may be impregnated in material(s) forming the water-containing elements. Further optionally, the anti-pathogen agent may be contained in a surface coating of the water-containing elements. Such an anti-pathogen agent may inhibit biofilm and / or bacterial growth in the water-containing elements and / or may serve to kill pathogens in the water-containing elements.

[0062] Any references made herein to orientation (e.g. top, bottom, upper, lower, front, back, and rear) are made for the purposes of describing relative spatial arrangements of the features of the apparatus, and are not intended to be limiting in any sense.

[0063] As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

[0064] In addition, the terms “a” or “an” are employed to describe elements and components of the invention. This is done merely for convenience and to give a general sense of the invention. This description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is means otherwise.

[0065] In view of the foregoing description it will be evident to a person skilled in the art that various modifications may be made within the scope of the invention. For example, embodiments in accordance with the invention are not limited to any of the particular materials disclosed herein. Other materials suitable for performing the function described herein for a particular material may also be utilized in embodiments of the invention.

[0066] The scope of the present disclosure includes any novel feature or combination of features disclosed therein either explicitly or implicitly or any generalisation thereof irrespective of whether or not it relates to the claimed invention or mitigate against any or all of the problems addressed by the present invention. The applicant hereby gives notice that new claims may be formulated to such features during prosecution of this application or of any such further application derived therefrom. In particular, with reference to the appended claims, features from dependent claims may be combined with those of the independent claims and features from respective independent claims may be combined in any appropriate manner and not merely in specific combinations enumerated in the claims.

Claims

CLAIMS1. An air-to-water generation system comprising: a water extraction unit for extracting water from an airflow, the water extraction unit comprising: an arrangement for implementing a refrigeration cycle, wherein the arrangement comprises a first evaporator and a second evaporator; a first water collection conduit, for collecting water from the first evaporator; a second water collection conduit, for collecting water from the second evaporator; a storage tank for receiving and storing water from the first and second water collection conduits; and a water treatment and dispensing unit, the water treatment and dispensing unit comprising: a dispensing unit, comprising a dispensing outlet controllable to dispense water responsive to input received via a user control interface, the dispensing outlet in fluid communication with the storage tank; and a controller operative to control operation of the dispensing unit.

2. A system according to any one of the preceding claims, further comprising a user control interface for receiving user input.

3. A system according to claim 2, wherein the user interface is operative, responsive to received user input, to control operation of a dispensing valve to dispense water from the dispensing outlet.

4. A system according to claim 3, wherein the dispensing valve operates to cause water to be dispensed from the dispensing outlet in direct response to input received via the user control interface.

5. A system according to any one of claims 2 to 4, wherein the user control interface comprises a mechanical element.

6. A system according to claim 5, wherein the mechanical element comprises a tap, lever, handle and / or button.

7. A system according to any one of claims 2 to 6, wherein the user control interface comprises an electronic element.

8. A system according to claim 7, wherein the electronic element comprises a button, a display a touch-screen display, and / or a motion sensing element.

9. A system according to any one of claims 2 to 8, wherein the user interface is operative to communicate a user input instruction to the controller.

10. A system according to claim 9, wherein the controller, responsive to a received user input instruction, is operative to control operation of a / the dispensing valve to dispense water from the dispensing outlet.

11. A system according to claim 10, wherein the dispensing valve operates to cause water to be dispensed from the dispensing outlet in response to a signal received from the controller, the signal output by the controller to the dispensing valve responsive to input received at the controller via the user control interface.

12. A system according to any of the preceding claims, wherein the arrangement further comprises a third evaporator, and wherein the water extraction unit further comprises a third water collection conduit, for collecting water from the third evaporator.

13. A water extraction unit for an air-to-water generation system, the water extraction unit for extracting water from an airflow, the water extraction unit comprising: an arrangement for implementing a refrigeration cycle, wherein the arrangement comprises a first evaporator and a second evaporator; a first water collection conduit, for collecting water from the first evaporator; and a second water collection conduit, for collecting water from the second evaporator.

14. A water extraction unit according to claim 13, wherein the arrangement further comprises a third evaporator, and wherein the water extraction unit further comprises a third water collection conduit, for collecting water from the third evaporator.

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