WO2012119182A1

WO2012119182A1 - Solar evaporation system

Info

Publication number: WO2012119182A1
Application number: PCT/AU2011/001484
Authority: WO
Inventors: Jonathan LIOW
Original assignee: Liow Jonathan
Priority date: 2011-03-09
Filing date: 2011-11-18
Publication date: 2012-09-13

Abstract

An exemplary embodiment of a solar-radiation water-evaporation- condensation system has an evaporation chamber having an enclosed internal space. A quantity of water can be held in the internal space and heated by solar radiation so as to be evaporated. The evaporation chamber has internal surfaces on which condensed-water from the water vapour can condense. The system also has an inlet through which the water is added into the internal space. The system has an outlet through which the condensed-water is removed and collected from the evaporation chamber. Portions of the internal surfaces are provided with an angled gutter that directs the condensed-water to the outlet.

Description

SOLAR EVAPORATION SYSTEM

Field of Invention

The present invention relates to solar-radiation evaporation-condensation system, particularly devices used on a small scale to provide potable water for one person or a very small number of people.

Background

Safe and accessible drinking water is a rare resource on the planet. As little as approximately 1 in 8 people in our world may not have access to potable water. A lack of potable water is said to be responsible for nearly 80% of sicknesses and diseases in the developing world.

Filtration methods, such as sand filters, charcoal filters and nano-membrane filters, may not be effective for removing contaminants such as f ioride, heavy metals and bacteria to a level required for good potable water, particularly in systems used in the community at grass-roots level in the developing world. Evaporation, however, is a process that is able to produce potable water by removing often up to 90% of contaminants, or possibly more.

Known evaporation systems may take the form of large structures or smaller personal devices. Of the latter, existing devices in the field may be either cumbersome to transport, complex requiring structural or technical setup, or may not function efficiently. Such known personal devices may require the user to dismantle the device in order to disperse the condensed water, thus, in the dismantling process, losing heat from the system.

An object of the present invention is to provide an improved alternative, and it is not necessary that the present invention solves each and every problem in the prior art.

Any discussion of prior art above and herein, either singly or in combination, is not to be construed as an admission of the state of common general knowledge of the skilled addressee. Summary of Invention

According to the present invention, there is provided a solar-radiation water- evaporation-condensation system comprising a combination of;

an evaporation chamber having an enclosed internal space that is able to hold a quantity of added-water therein such that, in use, any added- ater is able to be heated by solar radiation shining on the evaporation chamber and evaporated as water vapour into the internal space, and the evaporation chamber also having internal surfaces on which condensed-water from the water vapour can condense thereon; refill-means through which added-water is able to be added into the internal space; and

dispersion-means through which the condensed-water is able to be removed and collected from the evaporation chamber;

wherein portions of the internal surfaces are provided with an angled gutter that is able to direct the condensed-water to the dispersion-means.

Preferably, the angled gutter is able to collect the condensed-water therein.

Preferably, in use when the evaporation system is placed on a generally flat surface, the angled gutter is arranged so as to act as an inclined channel in which the condensed-water is able to flow down.

Preferably, the evaporation chamber comprises an upper-container-portion removably attachable to a lower-container-portion that is adapted to receive the added-water therein.

Preferabl , the internal surfaces of the upper-container-portion include flow- guide-means on which, in use when the evaporation system is placed on a generally flat surface, the condensed-water can condense thereon and which guide the condensed- water to flow thereon into the angled gutter.

Preferably, the flow-guide-means are curved.

Preferably, the evaporation chamber comprises a generally spherical shape, and preferably the angled gutter is circular and is arranged proximate a complete circumference of the generally spherical shape.

Preferably, the lower-container-portion forms a lower hemisphere of the generally spherical shape, and the upper-container-portion forms an upper hemisphere of the generally spherical shape, and the internal surfaces of the upper-container - portion comprise the flow-guide-means.

Preferably, the flow-guide-means also includes longitudinally radiating fins that project into the internal space from inner surfaces of the upper-container-portion commencing from the apex or from proximate the apex and longitudinally radiating a short distance therefrom.

Preferably, the upper-container-portion is removably attachable to a circular region on the lower-container-portion that, when attached, is proximate the angled gutter.

Preferably, the upper-container-portion is rotatable about the lower-container- portion on the circular region.

The upper-container-portion may be removably attachable to the circular region on the lower-container-portion using a bayonet-mount arrangement.

Alternatively, the upper-container-portion may be removably attachable to the circular region on the lower-container-portion using a screw-thread arrangement or a mechanical fastening arrangement.

Preferably, the lower-container-portion is provided with extra insulation means.

Preferably, the extra insulation means comprises a double- walled structure having at least two walls with an extra insulation region between the walls.

Preferably, the extra insulation region is filled with air.

Alternatively, the extra insulation region may have a vacuum therein or an insulating material.

Preferably, at least the upper-c ntainer-portion comprises transparent material. In an embodiment, at least the lower-container-portion may comprise opaque material.

The opaque material may be a black coloured material.

Preferably, in use, the system is able to receive the added- water, and disperse the condensed-water from the evaporation chamber, without the system having to be dismantled, lifted or tipped.

The refill means may comprise a refill point.

The dispersion-means may comprise a dispersion point.

The added-water may be contaminated water. Drawings

In order that the present invention might be more fully understood, embodiments of the invention will be described, by way of example only, with reference to the accompanying drawings, in which:

Figure 1 is a side cross-sectional view of an exemplary embodiment of a solar- radiation water-evaporation-condensation system when viewed from line A-A in Figure 4;

Figure 2 is a side cross-sectional view of a top-chamber of the embodiment of Figure 1 ;

Figure 3 is a side cross-sectional view of a bottom-chamber of the embodiment of Figure 1;

Figure 4 is a plan view of the embodiment of Figure 1 ; and

Figure 5 is a side view of the embodiment of Figure 1 , shown without cross- sectional representation.

In the drawings of the exemplary embodiment in Figure 1 to 4, internal components are shown as being visible through transparent parts of the apparatus. In Figures 1 to 4, the bottom-chamber is shown as if were made with transparent material so that features of the embodiment may be seen clearly, however. Figure 5 shows the embodiment as it appears where the bottom- chamber is made with opaque material.

Description oF Embodiments

Referring to the accompanying drawings, Figure I shows a side view of an embodiment of a solar-radiation water-evaporation-condensation system in the form of a solar water-purifier 10.

In Figure 1, the water-purifier 10 has an upper-container-portion in the form of a top-chamber 20, seen separately in Figure 2.

In Figure 1, the water-puriGer 10 also has a lower-container-portion in the form of a bottom-chamber 30, seen separately in Figure 3.

In Figure I, the top-chamber 20 is removably attached to the bottom-chamber 30 to form a structure that functions as an evaporation chamber in the form of evaporation housing 40A, 40B. The side view of Figure 1 , and the plan view of Figure 4, show that the solar water-purifier 10 is generally spherical in shape, although it is not perfectly spherical in that the sense that shaped-portions of the apparatus, for example at the base 60 and at an indentation 44 in the surface, mean that the overall water-purifier 10 is not a perfectly geometrical sphere.

The top-chamber 20 forms an upper hemisphere of the generally spherical shape of the water-purifier 10. The generally hemispherical shape of the top-chamber 20 enables solar radiation, coming from any angle, to shine into the evaporation housing as the sun moves across the sky during the course of each day. It also means that the water-purifier 10, in use in sunlight, does not need to be arranged in a certain orientation towards the sun, since the hemispherical top-cbamber is able to present a similar aspect of itself towards the sun largely irrespective of the angle of the rays of the sun during much of daylight hours, especially during those times of the day when solar radiation is most intense.

The bottom-chamber 30 forms a lower hemisphere of the generally spherical shape of the water-purifier 10. The hemispherical shape of the bottom-chamber 30 enables, throughout the day, as much as possible of the housing-inner-surface 41B of the bottom-chamber 30 to be arranged to receive the rays of the sun thereon. This enhances, as far as possible, the solar heating of the inner-surfaces 4 IB of the bottom chamber 30.

An advantage of a hemispherical-shaped bottom-chamber 30, in the embodiment of Figure 1, may be appreciated when contrasted with, for illustration, a cube-shaped chamber with vertical walls. When the sun is directly above a cube- shaped chamber, its vertical side walls would not be arranged to receive direct solar radiation, whereas a hemispherical chamber of similar width would present a greater surface area to be heated by the rays of the sun for a greater period of the day.

The evaporation housing 40A, 40B also has a generally spherical shape.

The flat base 60 of the water-purifier 10 enables the apparatus to be placed on the ground without it rolling. Figure I shows the side view of the solar water-purifier 10 as it appears when placed on level ground, with the flat base 60 seated on level ground. The base 40 may optionally be provided with a base-stand 41 having extended support arms 43 to provide further stability. In the plan view of Figure 4, the base-stand and its feet are shown, as if the bottom-chamber 30 were to be made from transparent material so that the stand 41 might be seen through the transparent bottom-chamber 30, however, in the embodiment where the bottom-chamber 30 is made from opaque material, such as black material, the base-stand 41 would not be visible in a plan view.

In Figure I, the outer surface of the bottom-chamber 30 may be provided with indentations 32 to facilitate the user gripping and handling the water-purifier 10 when it is being carried and transported. In Figure 1, the optional indentations are arranged in two rows around the outer surface of the bottom-chamber 30.

The evaporation housing 40A, 40B has an enclosed internal space that is made up of a combination of an internal space 40A of the top-chamber 20 together with an internal space 40B of the bottom-chamber 30. Together, the total internal space 40A, 40B in Figure 1 is in the form of a generally spherical volumetric region.

The internal space of the evaporation housing 40A, 40B is able to hold a quantity of added- water, typically in the form of contaminated or less-than-potable water. When water is added to the housing 40A, 40B, the water will collect at the bottom region 40C of housing. The shape of the bottom-chamber allows the bottom region 40C of the chamber to act as a reservoir for holding a quantity of added-water.

In use, the solar water-purifier 10 is placed in an open area so that solar radiation, or sunshine, is able to shine directly onto the water -purifier.

In the embodiment, the top-chamber 20 is made of transparent material such as, for example, a polycarbonate material or other suitable transparent material that can allow the solar radiation to shine into the interior of the water-purifier 10. In the embodiment of Figure 1, the bottom-chamber 30 is preferably made from an opaque material, such as a black or dark coloured version of the foregoing mentioned materials. Figure 5 shows a side view of the water-purified where the bottom-chamber 30 is made of opaque material and is not transparent.

In other modifications, the top and bottom chambers 20, 30 may alternatively be made from other materials such as polypropylene or polyethylene, and even optionally eco-recyclable materials such as corn-based plastics or bamboo-mixed plastics.

When solar radiation shines on the water-purifier 10, the evaporation housing 40A, 40B gradually heats up under the influence of the solar radiation. The housing 40A, 40B is an enclosed volumetric area, so the heated air inside the housing cannot readily escape from the water-purifier 10, which thus causes a gradual increase in the temperature inside the evaporation housing 40A, 40B. The increase in air temperature, inside the housing 40A, 40B, will also lead to a consequential increase in water-temperature of any added-water contained in the bottom region 40C of housing. Under such heating by the solar radiation, the water in the bottom region 40C will eventually evaporate as water vapour that will All the internal space of the evaporation housing 40A, 40B.

The solar water-purifier 10 is provided with refill-means in the form of a refill point 15. The refill point 15 of the water-purifier 10 is in the form of an aperture that is sealed with a removable cap 16 that has an internal screw thread. Added-water is able to be added into the internal space of the evaporation housing 40A, 40B.

Since added-water is able to be added through the refill point 15, it means that, when adding water, there is no need to neither detach the top-chamber 20 from the bottom-chamber 30, nor to tip or lift the purifier 10, so avoiding the loss of heat from the evaporation housing 40A, 40B which would otherwise occur from such detachment.

The evaporation housing 40A, 40B has internal surfaces in the form of housing-inner-surfaces 41A, 41B.

When the water vapour, that is in the evaporation housing 40A, 40B, cools as it contacts the housing-inner-surfaces 41 A, 41B, a result is that condensed-water from the water vapour can condense on the surfaces 41A, 41B that are above the waterline of the water at the bottom region 40C.

In Figure I, portions of the housing-inner-surfaces 41 A are provided with an angled gutter in the form of inclined-gutter 50. The inclined-gutter 50 is able to collect condensed-water that flows off the housing- inner-surfaces 41 A.

(n the embodiment, the inclined-gutter 50 is circular, and is provided around the circular rim of the top-chamber 20. Hence, the inclined-gutter 50 is also circular and ring-like in shape, In the embodiment of Figure 2, the inclined-gutter 50 is perferably arranged proximate the complete circumference of the generally spherical purifier 10 in the sense that the gutter 50 is circular and preferably completely circles the rim of the purifier 10.

In the midst of the ring-like inclined-gutter 50 is a circular open region 51. The internal space 40B of the bottom-chamber 30 and the internal space 40A of the top-chamber 20 are able to communicate through this circular open region 51.

The solar water-purifier 10 is provided with dispersion-means in the form of an exit- valve 70. The exit-valve is used to open and close an aperture opening that enables condensed-water, that has been collected in the inclined-gutter 50, to be removed and collected from the evaporation housing 40 A, 40B.

Since condensed-water is able to be removed through the exit-valve 70, it means that, when removing water, there is no need to neither detach the top-chamber 20 from the bottom-chamber 30, nor to tip or lift the purifier 10, so avoiding the loss of heat from the evaporation housing 40A, 40B which would otherwise occur from such detachment.

The inclined-gutter 50 is able to direct the condensed-water to the exit-valve 70. The exit- valve 70 is positioned proximate the lowest point of the inclined-gutter 50 so that all the condensed-water in the inclined-gutter 50 is able to flow out when the exit-valve 70 is opened.

In use, when the evaporation system is placed on a generally flat surface, the inclined-gutter 50 is arranged as shown in Figure 1 so as to act as an inclined channel in which the condensed-water is able to flow down towards the region of the exit- valve 70.

In the embodiment, the preferred use of a valve 70 enables condensed water to be removed, without opening up a substantially larger opening into the evaporation housing 40A, 40B which could otherwise lead to heat loss through such an opening.

In use, the evaporation system is able to receive the added-water, and disperse the condensed-water from the evaporation chamber, without the evaporation system having to be dismantled, lifted or tipped. In other words, there is no need to remove the top-chamber 20 from the bottom-chamber 30 which would otherwise cause loss of heat from the evaporation housing 40A, 40B. By avoiding such heat loss, it means there is no need for the evaporation housing 40A, 40B to be re-heated each time a portion of condensed water is dispensed from the apparatus, which would otherwise lengthen the time needed to condense a given amount of water. For example, a user may open the exit-valve 70 to pour one glass of water for himself without having to open up the entire apparatus to lose the heat that has built up in the evaporation housing 40 A, 40B.

The evaporation process leaves a substantial portion of contaminants, that were in the added-water, in the bottom region 40C, at least to the extent of allowing the condensed water to be in a potable state.

The interior of the evaporation housing 40A, 40B is not kept in a state of vacuum in the sense that its interior is open to the atmosphere through tiny openings in the structure which are small enough to avoid substantial temperature loss, but sufficient to keep the internet at ambient pressure. This avoids any inadvertent buildup of pressure inside the container through the heating process.

The refill-means is provided with a guide shaft 17 that guides the added-water to a point where it spills directly into bottom chamber bottom-chamber 30, with the guide shaft ensuring that the added-water avoids entering the inclined-gutter 50.

In use, when the solar water-purifier 10 is placed on a generally flat surface, as shown in Figure 1 and indicated in Figure 2, the housing-inner-surfaces 41A of the top-chamber 20 include flow-guide-means on which the condensed-water can condense and which guide the condensed-water to flow into the inclined-gutter 50.

In the embodiment of Figure 1, the flow-guide-means includes the housing- inner-surfaces 41 A of the top-chamber 20. Water condenses on these curved surfaces 41 A, and the water flows on these curved surfaces 41 A into the inclined-gutter 50.

The flow-guide-means may also include fins 42. In the embodiment of Figure 1, the fins project into the evaporation housing from inner surfaces of the ceiling of top-chamber 20, and commence from a region proximate but not directly on the apex 21 of the top-chamber. The fins longitudinally radiate for a short distance.

The fins at the apex 21 are able to guide at least some of the water, that condenses at the ceiling of the top-chamber 20, towards portions of the curved surfaces 41 A that have steeper angles of inclination, compared to the portion of the ceiling near the apex. When condensed water is guided to these portions, which have steeper inclination, at these locations there is less likelihood of the condensed water falling downwards and back to the bottom region 40C of the water-purifier 10.

In other embodiments, the fins may commence at the apex. In yet a further embodiment, longitudinally radiating fins may be found at lower portions of the inner-surfaces 41 A of the top-chamber 20.

In the embodiment of Figure 1, the top-chamber 20 is removably attachable to a circular region on the bottom-chamber 30 that, when attached, is proximate the inclined-gutter 50 of the top-chamber 20. In the embodiment of Figure 3, this circular region is in the form of a circular rim 31 of the bottom-chamber 30.

The circular rim 35 of the bottom-chamber 30 is perfectly circular, and the corresponding circular rim 25 of the top-chamber 20 is likewise perfectly circular. Both the upper and lower rims 25, 35 have the same diameter. The top-chamber 20 is rotatable about the bottom-chamber 30 on the circular region. In Figures 1 , 2 and 3, the top-chamber 20 is removably attachable to the circular region on the bottom-chamber 30 using a bayonet-mount arratigement Figure 3 shows a side view of a portion of a protruding flanged-claw 36 of the bayonet- mount arrangement. The flanged-claw 36 rotates in a circular groove 26 located the inner rim of the top-chamber 20.

In the embodiment, the circular rim 35 of the bottom-chamber 30 is arranged at an incline, rather than being horizontal, because the rims 25, 35 follow the inclination of the inclined-gutter 50.

In the embodiment of Figure 1, preferably the plane, in which the circular rims 25, 35 lie, passes generally through the centre point of the spherical shape of the water purifier 10. This positioning of the rims may offer a balance between providing sufficient volume for the inclined-gutter 50, versus providing sufficient volume for holding added-water in the bottom region 40C of the bottom-chamber 30. However, in other modifications, the plane that passes through the rims may either be raised or lowered relative to the centre point of the sphere, if required. Raising the location of the rims will allow more added-water to be stored in the bottom-chamber 30, while lowering the location of the rims relative to the centre point will increase the capacity of the inclined- gutter 50.

In the embodiment of Figure 1, the region near the rims of the top and bottom chambers may be provided with indication markings 28 to guide the user in the attachment and removal process. For example, the markings 28 may indicate to the user which way to twist the top and bottom chambers, relative to each other, in order to either open or close the apparatus. The markings 28 may include indications of whether rotation should start and cease, to avoid the user trying to twist the components beyond the point of ideal rotation.

In other modified embodiments, the top-chamber 20 may instead be removably attachable to the circular region on the bottom-chamber 30 using a screw- thread arrangement or a different mechanical fastening arrangement, such as a lever locking mechanism where the alignment is achieved by pin registration.

In the embodiment in Figure t , which is by way of example only, the diameter of the water purifier 10 is around 300 cm (i.e. with a radius of approximately 150 cm), and the exemplary apparatus without water weighs approximately 1.1 kg. Hence, the water purifier is sufficiently portable, and it is envisaged that such embodiments may be useful in developing world countries for producing small amounts of potable water for individuals or small groups of people.

In the embodiment of Figure 1, the bottom-chamber 30 is preferably provided with extra insulation means in the form of a double-walled structure having at least two walls 30, 30A with an extra insulation region between the walls.

In the embodiment of Figure 1, the extra insulation region is filled with air. The air gap acts as an insulator that minimises loss of heat from the bottom-chamber 30. By minimising heat loss from the bottom-chamber 30, there is a greater likelihood of a thermal difference between the top 20 and bottom 30 chambers, with the top chamber being more likely to be cooler than the bottom chamber, thus enhancing the likelihood of condensation forming on the surfaces of the upper chamber 20.

In other embodiments, the extra insulation region may have a vacuum therein or an insulating material. There are numerous insulating materials that may be used, such as fiberglass and other materials used in industry for insulation purposes.

In the embodiment of Figure 1, in order to enhance the insulation

characteristics of the bottom-chamber 30, the bottom-chamber 30 is preferably made from an opaque material, for example, a black-colored polycarbonate. The black material of the bottom-chamber 30, once it has been heated by the solar radiation, tends to retain the heat energy to a greater degree, as compared to lighter-coloured or transparent materials.

In other embodiments, the extra insulation means may be omitted and, for example, the bottom-chamber 30 may be made merely from a single outer layer 30 akin to the example of construction of the top-chamber 20.

Features of embodiments of the invention, by way of example, is summarized below:

Insulation of the contaminated water chamber (bottom-chamber) increases the speed of the evaporation process. Preferably, the insulation comprises a double wall 30, 30A, and the air between each wall retains the heat absorbed from the sunlight and from the ground.

The hemispherical form of the evaporation chamber (top-chamber) enables capturing of solar energy from every angle, and also allows condensation to flow down the entire surface area of the hemisphere.

The inner surface of the hemisphere may have fins or similar devices commencing at or near the apex of the ceiling that create a conduit for condensation which gathers on the wall of the evaporation chamber to drain into the collection gutter as opposed to dripping vertically back down into the contaminated water (bottom-chamber).

An embodiment of the evaporation system has two main parts; the hemispherical evaporation half (top-chamber 20), and the contaminated water half (bottom-chamber 30). These two chambers come apart for easy cleaning, as a build up of sediments and residue will be left in the bottom chamber over periods of continuous use.

This continuous purification system has two primary benefits. Firstly, it increases the efficiency of the evaporation process through mirumizing the loss of heat in the contaminated water chamber. Secondly, it enables the collection of purified water at any point of time in the evaporation process i.e. does not have to be collected only when all the contaminated water has been evaporated.

Finger indents 27 are preferably located on the sides of the device to aid in dismantling the two chambers, and putting them back together again.

The contaminated water chamber (bottom-chamber) is preferably

hemispherical overall in shape, with a flattened base to enable the invention to stand still when on a level plane.

The contaminated water chamber (bottom-chamber 30) may be constructed from black polycarbonate which is BPA safe, UV resistant, high-impact resistant, weather resistant, known for its ability to act as an insulator, and has an approximate lifespan of five years.

The dispersion valve 70, where purified water is dispersed, preferably has user symbols on the interface which indicate "open-close".

The re-fill lid 16, where contaminated water is inserted, preferably leads to a shaft 17 that acts as a conduit to ensure that contaminated water poured into the device flows directly into the contaminated water chamber and not the collection gutter, where purified water sits.

The collection gutter 50 preferably has a lip to reduce the risk that purified water will spill into the contaminated water chamber 40B.

The contaminated water chamber 40B preferably has a horizontal guiding line to indicate to users the most suitable amount of contaminated water to insert in order for the device to operate at maximum efficiency. There is preferably a bayonet fitting which secures the evaporation hemisphere (top-chamber) to the contaminated water chamber (bottom-chamber) which locks the two halves together securely, keeping the device sealed during the evaporation process.

Contaminated water is poured into the re- fill point 15 which is guided by the shaft 17 to the double-walled contaminated water chamber (bottom-chamber 40B). Direct sunlight and radiant heat warms up the device 10. As the temperature of the contaminated water increases, evaporation commences and condensation forms on the ceiling of the hemispherical evaporation chamber (top-chamber 20). The

condensation is guided by the fins and drips down the inside walls of the upper hemisphere to the collection gutter. The tilt of the collection gutter drains the purified water toward the dispersion point, Purified water is dispersed without the need to lift, tilt or dismantle the device. Contaminated water can be re-filled at any point during the evaporation process without dismantling the device.

The device provides an improved evaporation system that is simple, cheap, efficient, low- tech, low maintenance and enables continuous purification.

The embodiments have been advanced by way of example only, and modifications are possible within the scope of the invention as defined by the appended claims.

In a modified embodiment, the evaporation chamber need not be spherical, but may alternatively be oval-shaped, or even cube-shaped or other appropriate shape that can embody the features of the invention in its broadest aspect as defined by appended claim 1.

There can be a number of alternative mechanisms or structures to modify the refill point 15 and the exit- valve 70, which were given as examples. For instance, the refill-means may be embodied as a press-fit stopper with perhaps a mechanical lock, while the dispersion-means may be formed as a tap mechanism and according to other water valve designs.

In other embodiments, there may be two or more refill points or dispersion points,

In other modified embodiments, there is no need for a valve 70. Instead, the condensed water can flow continuously into an external collection reservoir. In other embodiments, there is no need for a cap 16. Instead, there can be a supply of incoming water that is stopped and started automatically by an electronic sensor system that detects the level of water remaining in the bottom-chamber 30.

In the specification, the use of the plural word surfaces has been chosen to describe the inner surfaces of the hemispherical chambers, given the choice of referring to a sphere having inner surfaces or an inner surface. Suffice it to say, the vise of the plural in the specification should not be used to import a physical limitation to the invention in its broadest aspect.

In this specification, the term solar radiation is used generally to mean that energy from the sun which is able to heat the water in the water-evaporation- condensation system.

The invention as defined by the appended claims excludes any art that does not make use of solar radiation in the process of producing potable water.

In this specification, where the words comprise or comprises or derivatives thereof are used in relation to elements, integers, steps or features, this is to indicate that those elements, integers, steps or features are present but it is not to be taken to preclude the possibility of other elements, integers, steps or features being present.

Claims

CLAIMS:

1. A solar-radiation water-evaporation-condensation system comprising a combination of:

an evaporation chamber having an enclosed internal space that is able to hold a quantity of added- water therein such that, in use, any added- water is able to be heated by solar radiation shining on the evaporation chamber and evaporated as water vapour into the internal space, and the evaporation chamber also having internal surfaces on which condensed-water from the water vapour can condense thereon; refill-means through which added-water is able to be added into the internal space; and

2. A system of claim 1 wherein the angled gutter is able to collect the condensed- water therein.

3. A system of claim 1 or 2 wherein, in use when the evaporation system is placed on a generally flat surface, the angled gutter is arranged so as to act as an inclined channel in which the condensed-water is able to flow down.

4. A system of any one of claims 1 to 4 wherein the evaporation chamber comprises an upper-container-portion removably attachable to a lower-container- portion that is adapted to receive the added-water therein.

5. A system of claim 4 wherein the internal surfaces of the upper-container- portion include flow-guide-means on which, in use when the evaporation system is placed on a generally flat surface, the condensed-water can condense thereon and which guide the condensed-water to flow thereon into the angled gutter,

6. A system of claim 5 wherein the flow-guide- means are curved.

7. A system of claim 5 or 6 wherein the evaporation chamber comprises a generally spherical shape,

and wherein the angled gutter is circular and is arranged proximate a complete circumference of the generally spherical shape.

8. A system of claim 7 wherein the lower-container-portion forms a lower hemisphere of the generally spherical shape,

and the upper-container-portion forms an upper hemisphere of the generally spherical shape,

and wherein the internal surfaces of the upper-container-portion comprise the flow-guide-means .

9. A system of any one of claims 5 to 8 wherein the flow-guide-means also includes longitudinally radiating fins that project into the internal space from inner surfaces of the upper-container-portion commencing from the apex or from proximate the apex and longitudinally radiating a short distance therefrom.

10. A system of any one of claims 4 to 9 wherein the upper-container-portion is removably attachable to a circular region on the lower-conlainer-portion that, when attached, is proximate the angled gutter.

1 1. A system of claim 10 wherein the upper-container-portion is rotatable about the lower-container-portion on the circular region.

12. A system of claim 10 or 1 1 wherein the upper-container-portion is removably attachable .to the circular region on the lower-container-portion using a bayonet- mount arrangement.

13. A system of claim l O or 11 wherein the upper-container-portion is removably attachable to the circular region on the lower-container-portion using a screw-thread arrangement or a mechanical fastening arrangement.

14. A system of any one of claims 4 to 13 wherein the lower-container-portion is provided with extra insulation means.

15. A system of claim 14 wherein the extra insulation means comprises a double- walled structure having at least two walls with an extra insulation region between the walls.

16. A system of claim 15 wherein the extra insulation region is filled with air.

17. A system of claim 15 wherein the extra insulation region has a vacuum therein or an insulating material.

18. A system of any one of claims 4 to 17 wherein at least the upper-container- portion comprises transparent material.

19. A system of any one of claims 4 to 18 wherein at least the lower-container- portion comprises opaque material.

20. A system of claim 1 wherein at least the opaque material is a black coloured material.

21. A system of any one of the preceding claims wherein, in use, the system is able to receive the added-water, and disperse the condensed-water from the evaporation chamber, without the system having to be dismantled, lifted or tipped.

22. A system of any one of the preceding claims wherein the refill means comprises a refill point

23. A system of any one of the preceding claims wherein the dispersion-means comprises a dispersion point.

24. A system of any one of the preceding claims wherein the added-water is contaminated water.