WO2009073929A1

WO2009073929A1 - Solar distillation device

Info

Publication number: WO2009073929A1
Application number: PCT/AU2008/001832
Authority: WO
Inventors: Rodney Bourchier
Original assignee: H2Oasis Energy Pty Ltd
Priority date: 2007-12-13
Filing date: 2008-12-12
Publication date: 2009-06-18
Also published as: AU2008336266A1

Abstract

The present invention relates to a solar distillation/desalination device comprising an integral structure separated into two or more chambers. In the case of purifying saline water, the system created by the dual chamber pipe works using the principle of evaporation to produce desalinated water. Evaporated water that collects in the holding chamber will condense inside the chamber and flow along the sides of the pipe into separate collection chambers. Water can either be released at regular intervals for irrigation purposes or the water can be collected at designated locations along the pipe for drinking. The concentrated salt water that remains will then be returned to its source through proper placement of the pipe.

Description

Solar Distillation Device

The present invention relates to a solar powered water desalination and distillation device, specifically, distributed desalination for irrigation or drinking water.

BACKGROUND OF THE INVENTION

In large parts of the world fresh water resources are limited. Water for drinking and for irrigation therefore has to be produced from brackish water or sea water. The most common water purification methods to date have been designed for centralized use in locations along dry, ocean coasts. Inventions useful in the desalination of water have focused on complicated and expensive machinery to make water potable. Many previous inventions also rely heavily on electrical power to fuel the desalination process, further adding cost to the desalination process.

In recent years the focus in desalination has been to harness solar power for use in desalination of water, thus making potable water somewhat cheaper to produce. However, these recent inventions still rely on the concept of localized factory style processing plants for salinated water drawn from the ocean. This method of water desalination causes the costs for the production of complicated machinery and shipping of fresh water to keep desalination from being a viable option for many localities around the world.

One disadvantage of the known devices is that they are relatively bulky, expensive and stringent requirements must be met with respect to periodic maintenance. The construction of these known devices often requires trained construction crews to assemble.

Another disadvantage of these known devices is that they rely on a factory style paradigm for the creation of water. This has the effect of making the process of desalination centralized, and therefore fresh water created by a desalination process is created in one location.

It is an object of the present invention to overcome at least some of the aforementioned problems or provide the public with a useful alternative.

It is a further object of the present invention to provide a method of desalination that is mass producible by using single piece plastic extrusions. It is a still further object of the present invention to make it possible to desalinate water across large expanses of territory, without the need to incur additional distribution costs.

It is a yet further object of the present invention to improve upon previous desalination devices by decreasing the cost of desalination equipment as well as de-centralizing the process of desalination, thereby making the desalination of water efficient for irrigation as well as in the creation of potable water.

SUMMARY OF THE INVENTION

Therefore in one form of the invention there is proposed a device for treating liquid, said device characterised by: at least one chamber for holding said liquid; at least one collection chamber; a means of heating said at least one holding chamber to cause said liquid to evaporate; and a surface for forming condensate resulting from said evaporation, and directing said condensate into said at least one collection chamber.

Preferably said means of heating the liquid holding chamber is solar energy.

In preference said device further includes a means of assisting said heating of the holding chamber using solar energy.

In preference said means of assisting solar heating is in the form of a lens used to focus the solar energy onto said liquid. Preferably said lens is a Fresnel lens.

In preference said holding chamber includes a surface for absorbing some of said focused heat to prevent damage to said device.

Preferably said heat absorbing surface is a ceramic surface.

In preference said device further includes a means of removing treated liquid from said at least one collection chamber for use.

In preference said holding and collection chambers are housed inside a substantially enclosed, box-like structure. Alternatively, said holding and collection chambers are housed inside a substantially enclosed, extruded structure.

Preferably the cross section of said extruded structure is hemispherical in shape having a flat base, whereby said chambers are defined and separated by internal partitions upstanding from said base.

In preference said structure and said internal partitions are integrally formed.

Preferably said structure is constructed from heat resistant material such as Polyvinyl Chloride (PVC) or fibreglass.

Preferably said device is portable.

In preference said liquid is saline water, and the condensate collected in said collection chamber is treated, substantially desalinated fresh water.

In a further form of the invention there is proposed a solar distillation/desalination device for use in association with corrugated roof sheets having a plurality of peaks and troughs, said solar distillation device characterised by at least one elongated structure having a flat base and an upright body shaped to be housed inside a peak of said corrugated roof sheet, said elongated structure including at least one internal partition upstanding from said base separating at least one liquid holding area from at least one liquid collection area, whereby solar energy that is absorbed by said roof sheet heats the liquid holding area and causes evaporation of said liquid, said upright body including a surface to collect condensate resulting from said evaporation and direct said condensate into said liquid collection area.

In preference said flat base, upright body and internal partitions are integrally formed.

Preferably said upright body is a substantially enclosed hemispherical body, said condensation collection surface being a ceiling of said hemispherical body.

In a still further form of the invention there is proposed a solar distillation/desalination roof system including a solar distillation device as characterised above.

Preferably each peak of said corrugated roof sheets includes one of said solar distillation devices. Preferably said system further includes a liquid storage area adapted to store liquid which accumulates in each of said liquid collection areas.

In a yet further form of the invention there is proposed a solar distillation/desalination device for use in irrigating a ground surface, said device characterised by an extruded structure adapted to be placed in the proximity of said ground surface to be irrigated, said structure including a box-like cross section having at least one liquid holding area and at least one liquid collection area, whereby solar energy that is absorbed by said device heats the liquid holding area and causes evaporation of said liquid, said structure including a surface to collect condensate resulting from said evaporation, and direct said condensate into said liquid collection area.

Preferably said device further includes a means of dispersing liquid which accumulates in said liquid collection area into the surrounding ground surface.

Preferably said device further includes a means of assisting solar heating of the liquid holding area.

In preference said means of assisting solar heating is in the form of a lens used to focus the solar energy onto said liquid.

Preferably said lens is a Fresnel lens.

In preference said liquid holding area includes a surface for absorbing some of said focused heat to prevent damage to said device.

Preferably said heat absorbing surface is a ceramic surface.

The device of the present invention therefore consists of a one piece article of manufacture, which is essentially a pipe or a box partially separated into two chambers. This separation is achieved using one or more specially shaped and oriented dividers which are internal to an outer shell, yet forming part of the outer shell. In the case of purifying saline water, the system created by the dual chamber pipe works using the principle of evaporation to produce desalinated water. Water from a salinated water source for example, such as the ocean, is pumped from the source to inland areas. The water is then allowed to flow downhill through the bottom chamber of the apparatus. As the water flows down hill, the sun and radiant ground heat will cause the water to evaporate. Evaporated water that collects in the holding chamber will condense inside the chamber and flow along the sides of the pipe into separate collection chambers. Water can either be released at regular intervals for irrigation purposes or the water can be collected at designated locations along the pipe for drinking. The concentrated salt water that remains will then be returned to its source through proper placement of the pipe.

The present invention therefore represents a departure from previous desalination devices in its lower cost of manufacture, simplicity of construction and low operational costs. It further differs from previous devices in its non-local delivery of fresh water, making the system economically feasible for irrigation.

DESCRIPTION OF DRAWINGS

The above and other objects, features, and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment in conjunction with the accompanying drawings. In the drawings:

Figure 1 illustrates a cross sectional view of a solar distillation device according to a first embodiment of the present invention;

Figure 2 illustrates a cutaway perspective view of the solar distillation device of Figure 1;

Figure 3 illustrates a cutaway perspective view of a plurality of solar distillation devices according to a first embodiment;

Figure 4 illustrates a cross sectional view of a solar distillation device according to a second embodiment of the present invention;

Figure 5 illustrates a cross sectional view of a solar distillation device according to a third embodiment of the present invention;

Figure 6 illustrates in schematic perspective view a solar distillation device according to a fourth embodiment of the present invention; Figure 7 illustrates in schematic perspective view the solar distillation device of Figure 6 in an extruded form;

Figure 8 illustrates in schematic perspective view a plurality of the solar distillation devices of Figure 6; Figure 9 illustrates a cross sectional view of solar distillation devices according to a fifth embodiment of the present invention;

Figure 10 illustrates a cutaway perspective view of the solar distillation devices of Figure 9. Figure 11 illustrates a cross sectional view of a solar distillation device according to a sixth embodiment of the present invention; and

Figure 12 illustrates in schematic perspective view an extruded version of the solar distillation device of Figure 11 positioned around a tree.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Shown in the drawings is a solar distillation device 10a (Figures 1-3), 10b (Figure 4), 10c

(Figure 5), 1Od (Figures 6-8), 1Oe (Figures 9-10) and 1Of (Figures 11-12). In each case the devices operate on similar principles and have a number of features in common. In particular, each device works using the principle of evaporation and condensation to produce treated liquid. Where like features are described in the drawings, like numerals will be used to refer to these features. It is to be further understood that the device of the present invention has application in a wide range of environments and could be used to treat a wide range of liquids not limited to saline water.

The solar distillation devices 10a- 1Oe essentially comprise an outer shell 12 and at least one dividing element 14 which separates a chamber 16 containing untreated liquid 18 from chambers 20 containing treated liquid 22 resulting from the evaporation and condensation process described below. As will become apparent, the device is not intended to be limited to having only one of each of these chambers.

Turning firstly to device 10a in Figures 1-3, the outer shell 12 is in the form of an extrusion having a substantially hemispherical cross sectional shape. In the embodiment shown, there are two internal dividing elements 14 which extend in a curved manner from the inside corners of the hemisphere, inwardly and upwardly to just beneath the ceiling 24 of the outer shell 12. The outer shell 12 and dividing elements 14 are preferably integrally formed. As the arrows in Figure 1 indicate, when untreated liquid 18 in chamber 16 is heated, by way of solar energy 26 for example, the liquid evaporates to form gas particles 28 which rise to the ceiling 24, where they condense to form a liquid again, which flows down along the curved ceiling 24 into chambers 20. The resultant liquid 22, as those skilled in the art would realise, is of a more pure form than the untreated liquid 18 flowing through chamber 16.

If for example the untreated liquid in chamber 16 is salt water, the device 10a provides a means of evaporating the flow of salt water, collecting the evaporate, allowing the evaporate to condense, and collecting the condensate. Although not specifically shown in this embodiment, the condensed fresh water is adapted to be released for irrigation and drinking for example, whilst the highly saline water remaining in chamber 16 is removed from the system or released to return to its source. Figure 3 illustrates an example of where a plurality of such devices positioned adjacent one another could be used.

Devices 10b and 10c are illustrated in Figures 4 and 5 respectively and, as mentioned, work in the same way as device 1 Oa but are configured slightly differently. In particular, device 10b is still hemispherical but is located on an angled surface and includes only one of the curved dividing elements 14 of device 10a. Alternatively, device 10c includes a circular outer shell 12 having a dividing element which extends from one internal side thereof inwardly and upwardly in a similar fashion to the dividing elements of devices 10a and 10b.

While devices 10a- 10c may be in the form of extruded pipelines or hoses, the outer shell 12 of the device of the present invention could equally well be configured differently to suit particular environments, for example, when the present invention is used to treat water in the domestic environment. The embodiments shown in figures 6-10 illustrate such applications.

For example, Figures 6-8 shows a solar distillation device 1Od in the form of a surface- mountable structure. The outer shell 12 in this case is a box-shaped tank and the dividing element 14 is a plate which separates two chambers as per the previous embodiments. The surface which causes condensed liquid to flow into chamber 20 is the diagonal surface 24 of the outer shell 12. A further feature of device 1Od is that it includes a means of increasing the heat inside the shell 12 to facilitate evaporation. The heating means is in the form of a Fresnel lens 30, or other similar lens, which is positioned to focus heat from the sun onto the untreated liquid 18. There is an outlet 32 positioned at the base of chamber 20, and an attached hose 34 for releasing the treated liquid for use. Figure 7 illustrates an extruded form 36 of the device 1Od in which there are a plurality of lenses 30 used, while Figure 8 illustrates three devices 1Od mounted to a single surface, for example, a wall. Such configurations could be used in a home for example, where rain water could be stored in chamber 16 and evaporated and condensed using the method of the present invention to form treated water in chamber 20.

The solar distillation devices can be placed in areas where heat from the sun is at a maximum, for example, in the roof of homes. For example, Figures 9-10 illustrate devices 1Oe mounted beneath peaks of corrugated roofing panels 38 which absorb significant heat from the sun. The added benefit to this also is that the solar distillation devices 1Oe are hidden from view. In the embodiment shown, the roofing panel 38 is fixed to frame members 40 which are in turn fixed to supporting cross beams 42. The device 1Oe illustrated is similar to device 10a previously described in that it is hemispherical in shape and includes two internal dividing elements 14, however, it differs slightly in that the treated liquid chambers 20 include exit channels 44 at the base of the dividing elements 14 allowing treated liquid 22 to drip into storage chambers 46 suspended beneath the cross beams 42. Treated water can then be easily retrieved from the storage chambers 46.

A further embodiment could be that the roofing panels are configured so that rain water trickles down and ponds horizontally in small ponding chambers (not shown) extending horizontally along the roof surface. The chambers are configured so that water which ponds evaporates and condenses within the chambers according to the principles described above, and may then be run off for use.

Figure 11 illustrates a still further embodiment of the invention and Figure 12 illustrates a possible application of this embodiment. Although the configuration of the device 1Of is slightly different, it still works under the same principles as the devices 10a- 1Oe described above. The device 1Of includes a heating compartment 48 which is a box-like structure including a Fresnel lens 50 positioned to focus heat energy from the sun inside the compartment. Water inside the compartment 48 is dripped from a main line 52 which houses untreated water. The heating compartment is therefore configured to facilitate evaporation of the water from the main line 52. A ceramic dish 54 is located at the bottom of the compartment 48 to absorb concentrated hear from the Fresnel lens 50 and thereby prevent potential damage to the compartment surface, which is typically constructed of plastic material.

Evaporated gas travels up through port 56 and into a condensing dome 58 mounted above the compartment 48. Between the condensing dome 48 and the heating compartment 48 is a runoff chamber 60 having an angled lower surface for allowing condensed water from the condensing dome treated water to run off the sides of the condensing dome 58 to be put to use. In Figure 12 there is shown a tree 62 having an extruded version 64 of the device 1Of extending around the tree 62. There is shown a plurality of Fresnel lenses 50 for heating the water inside the heating compartment 48 which extends around the tree 62. Those skilled in the art would realise that treated water that is substantially free from salt can then be used to water the soil around the tree, by way of drip watering using treated water from the run-off chamber 60.

Modifications of device 1Of could also be used. For example, it could be constructed so that the main line is positioned around the condensing dome to provide cooling to the dome to facilitate condensation. Such configurations could also be applied in other environments, for example, in lawn watering systems. The heating compartment 48 described above could be used to preheat water at the surface utilising energy from the sun, such water than being transported to the solar distillation devices positioned beneath the surface. This would be especially beneficial in colder weather environments. The present invention is not intended to be limited to any one evaporating/condensing configuration.

The devices 10a- 1Of can be manufactured from any material that is suitable to carry water for human consumption. Material should also be chosen that will be able to stand the heat which will be produced by solar radiation, as well as radiant ground heat. The recommended material in terms of cost and relative endurance is Polyvinyl Chloride (PVC) or fiberglass. PVC will allow for cost effective construction by means of plastic extrusion. Lengths of individual sections of pipe can vary according to the methods of manufacture available for each material.

The length and diameter of the devices 10a- 1Of will depend on surrounding environmental variables, for example, whether it is industrially or domestically used. Precipitated salts and minerals can build up in the pipe and cause a backup of the system resulting in an overflow of the chambers, and for this reason it is recommended that the devices be flushed out at regular intervals. A larger diameter pipe will allow for a greater rate of evaporation as the surface area of the salt water flowing through chamber 16 will be increased.

The skilled addressee should now realise the potential benefits provided by the present invention. The invention has been described by way of example. The examples are not, however, to be taken as limiting the scope of the invention in any way. Modifications and variations of the invention such as would be apparent to a skilled addressee are deemed to be within the scope of the invention.

Further advantages and improvements may very well be made to the present invention without deviating from its scope. Although the invention has been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope and spirit of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus.

In any claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is used in the sense of "including", i.e. the features specified may be associated with further features in various embodiments of the invention.

Claims

1. A device for treating liquid, said device characterised by: at least one chamber for holding said liquid; at least one collection chamber; a means of heating said at least one holding chamber to cause said liquid to evaporate; and a surface for forming condensate resulting from said evaporation, and directing said condensate into said at least one collection chamber.

2. A device as characterised in claim 1 wherein said means of heating the liquid holding chamber is solar energy.

3. A device as characterised in claim 2 further including a means of assisting said heating of the holding chamber using solar energy.

4. A device as characterised in claim 3 wherein said means of assisting solar heating is in the form of a lens used to focus the solar energy onto said liquid.

5. A device as characterised in claim 4 wherein said lens is a Fresnel lens.

6. A device as characterised in claim 3 or claim 4 wherein said holding chamber includes a surface for absorbing some of said focused heat to prevent damage to said device.

7. A device as characterised in claim 6 wherein said heat absorbing surface is a ceramic surface.

8. A device as characterised in any one of the above claims further including a means of removing treated liquid from said at least one collection chamber for use.

9. A device as characterised in any one of the above claims wherein said holding and collection chambers are housed inside a substantially enclosed, box-like structure.

10. A device as characterised in any one of claims 1-8 wherein said holding and collection chambers are housed inside a substantially enclosed, extruded structure.

11. A device as characterised in claim 10 wherein the cross section of said extruded structure is hemispherical in shape having a flat base, whereby said chambers are defined and separated by internal partitions upstanding from said base.

12. A device as characterised in claim 11 wherein said structure and said internal partitions are integrally formed.

13. A device as characterised in any one of the above claims wherein said structure is constructed from heat resistant material such as Polyvinyl Chloride (PVC) or fibreglass.

14. A device as characterised in any one of the above claims wherein said device is portable.

15. A device as characterised in any one of the above claims wherein said liquid is saline water, and the condensate collected in said collection chamber is treated, substantially desalinated fresh water.

16. A solar distillation/desalination device for use in association with corrugated roof sheets having a plurality of peaks and troughs, said solar distillation device characterised by at least one elongated structure having a flat base and an upright body shaped to be housed inside a peak of said corrugated roof sheet, said elongated structure including at least one internal partition upstanding from said base separating at least one liquid holding area from at least one liquid collection area, whereby solar energy that is absorbed by said roof sheet heats the liquid holding area and causes evaporation of said liquid, said upright body including a surface to collect condensate resulting from said evaporation and direct said condensate into said liquid collection area.

17. A solar distillation/desalination device as characterised in claim 16 wherein said base, upright body, and internal partitions are integrally formed.

18. A solar distillation/desalination device as characterised in claim 16 or claim 17 wherein said upright body is a substantially enclosed hemispherical body, said condensation collection surface being a ceiling of said hemispherical body.

19. A solar distillation/desalination roof system including a solar distillation device as characterised in any one of claims 16-18.

20. A solar distillation/desalination roof system as characterised in claim 19 wherein each peak of said corrugated roof sheets includes one of said solar distillation devices.

21. A solar distillation/desalination roof system as characterised in claim 19 or claim 20 wherein said system further includes a liquid storage area adapted to store liquid which accumulates in each of said liquid collection areas.

22. A solar distillation/desalination device for use in irrigating a ground surface, said device characterised by an extruded structure adapted to be placed in the proximity of said ground surface to be irrigated, said structure including a box-like cross section having at least one liquid holding area and at least one liquid collection area, whereby solar energy that is absorbed by said device heats the liquid holding area and causes evaporation of said liquid, said structure including a surface to collect condensate resulting from said evaporation, and direct said condensate into said liquid collection area.

23. A solar distillation/desalination device as characterised in claim 22 further including a means of dispersing liquid which accumulates in said liquid collection area into the surrounding ground surface.

24. A solar distillation/desalination device as characterised in claim 22 or claim 23 further including a means of assisting solar heating of the liquid holding area.

25. A device as characterised in claim 24 wherein said means of assisting solar heating is in the form of a lens used to focus the solar energy onto said liquid.

26. A device as characterised in claim 25 wherein said lens is a Fresnel lens.

27. A device as characterised in claim 24 or claim 25 wherein said liquid holding area includes a surface for absorbing some of said focused heat to prevent damage to said device.

28. A device as characterised in claim 27 wherein said heat absorbing surface is a ceramic surface.