GB1603661A

GB1603661A - Water collection devices

Info

Publication number: GB1603661A
Application number: GB14707/77A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-05-26
Filing date: 1978-05-26
Publication date: 1981-11-25

Description

(54) IMPROVEMENTS IN AND RELATING TO WATER COLLECTION DEVICES (71) I, JAMES ARTHUR CRAB TREE, a British Subject of 4, Springhead, Ashwell, Hertfordshire, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: Field of invention: This invention concerns dew condensers and the use of such devices as irrigation aids. In particular the invention is intended to aid the growth of vegetation in arid conditions and typically combines apparatus for irrigation with a particular plant, the one complementing the other to assist in reclaiming desert and semi-desert terrain.

Objects of the invention It is an object of the present invention to provide a device for condensing airborne moisture to form dew with means for collecting and storing the dew so formed.

It is another object of the present invention to provide modifications of the basic device for use under varying climatic conditions.

It is another object of the present invention to provide a combination of irrigation device and plant which can be left unattended for years at a time and which will constitute the basic re-stocking of desert and semi-desert areas with plant life which once established will bind together the upper layers of the soil and reduce erosion and create shelter sufficient to allow other less hardy vegetation to gain a foothold. Once a certain level of vegetation has been established it is then relatively straightforward to irrigate the area concerned and establish less hardy vegetation and thereby gain areas of land which hitherto have been totally unsuitable for farming or the growth of any vegetation.

The invention According to the present invention a dew condenser comprises a support, at least one condensing surface carried by the support on which airborne moisture will condense under appropriate climatic conditions, collector means associated with the condensing surface into which the condensate will drain and means for conveying the condensate to a reservoir, at least the condensing surface being electrically insulated from earth to permit electrostatic charge to build up on the condensing surface.

Preferably the condensing surface is either vertical or at an angle of less than 90" to the vertical so that condensate formed thereon will drain naturally under gravity into the collecting means.

Typically the condensing surface is formed from a sheet of metal and the collecting means comprises a channel formed along at least one edge of the metal sheet into which condensate will drain off the surface of the sheet.

The metal sheet may be flat and in the form of a vane which itself is rotatable about the support to take account of prevailing wind conditions so that the condensing surface is not normally presented broadside to the wind but aligns with the direction of the wind so as to present the minimum surface area and enhance use of the electrostatic effect of wind friction to attract moisture. This is of considerable importance in areas of high wind velocity and is also of importance in sandy areas where the winds will produce drifting of the sand and will cause the sand to build up against any projection. By reducing the area exposed to the winds so the build-up of sand and the like under such conditions is reduced to the minimum.

In an alternative embodiment the condensing surface is an inverted conical surface which may be formed from a plurality of triangular segments so that natural drainage will occur towards the apex of the cone both on the inside and outside surface thereof.

The surface area is further improved by providing fins on the surface of the cone internally or externally or both.

Preferably the reservoir is situated below ground level and pipe means serves to convey condensate from the collector means to the reservoir.

Conveniently the support serves a dual purpose and at least in part constitutes a tube through which condensate can flow to the reservoir which as mentioned may be situated below ground level.

According to a preferred feature of the invention the reservoir comprises a sac of plastics material or the like having an opening through which condensate can pass which is sealed to the lower end of the tube leading from the collector means and the sac is situated in a subterranean chamber.

Where a natural subterranean chamber is not available, the latter is preferably formed by an underground explosion and the sac is introduced into the chamber so formed through the tube by which the explosive charge is introduced into the earth to create the explosion to form the chamber.

A chamber formed by an underground explosion in this way is called a camouflet chamber.

Where the reservoir of condensate is to provide life support water means is preferably provided for tapping the water contained within the sac and drawing off same.

To this end for example a small bore tube may be introduced through the pipe leading from the collector means to the subterranean chamber so as to pass through the opening in the sac into the interior thereof.

Water can then be withdrawn through the small bore tube by a withdrawal pump preferably of the self-priming type.

Where the apparatus is to be used for irrigation purposes, the sac may be formed at least in part from a porous material so that water collected in the interior of the sac can seep to the exterior and provide a source of moisture below the ground level which can be tapped by roots of plants situated within an appropriate distance from the underground chamber.

Alternatively the sac may be perforated to allow water to drain out through the perforations to provide irrigation.

According to a further feature of the present invention, the sac includes an aperture and a closure member which can be operated remotely from above the ground whereby water collected within the reservoir sac can be retained therein and discharged for irrigation purposes into the subsoil in a controlled manner. Preferably the closure device operates in such a way as to partially or completely close the aperture so that by adjusting the position of the closure device between the fully open and fully closed positions, varying degrees of flow rate can be obtained.

According to a particularly preferred feature of the invention an irrigation device for collecting airborne moisture and storing same in a subterranean reservoir, embodying the invention is combined with at least one hardy shrub planted in close proximity to the irrigation device, the plant being of the type which forms a large root system for collecting water before creating much if any top structure whereby the soil is bound together by the root system of the plant and erosion around the plant and in the immediate vicinity is reduced.

A preferred plant comprises the mesquite tree which is commonly found in Arizona and Central American deserts.

It is a characteristic of this tree that if provided with sufficient moisture for growth the plant establishes a complex root system which seeks out water to almost any depth before any top structure of the plant begins to grow. The plant is not confused by local irrigation but still sends down its tap root system to seek its own natural sources of water before the main shoot breaks the surface of the ground and in consequence long before the tree is established, the root system of the plant begins to bind the ground together and prevents the soil from being washed away or eroded by wind and the like.

According to another preferred feature of the invention, once the land has been reclaimed in the manner outlined and plants such as the mesquite tree have been established at least below ground level if not above, other shrubs and plants such as the hoboba shrub may be planted near and around the irrigation devices. The hoboba shrub produces beans which when crushed yield oil and a residue which has been found to be a nutritious protein.

According to another aspect of the present invention, an irrigation scheme for arid and semi-arid land in which the climatic conditions are such that water can be collected from airborne moisture by a condensing action, comprises a plurality of irrigation devices embodying the invention of the type described, the device being spaced apart over the area to be irrigated with the distance between adjoining devices being such that trees and shrubs planted in between the said irrigation devices can obtain sufficient moisture from the soil around the devices to promote growth.

Typically the devices are arranged at the intersections of an imaginary matrix of two orthogonal sets of parallel lines and the spacing between the imaginary intersections of the matrix and therefore the locations of the irrigation devices is selected having regard to the average quantity of water which each device is likely to collect given the climatic conditions prevailing in the area, the type of soil and the nature and number of plants which are to be irrigated.

The invention will now be described by way of example with reference to the accompanying drawings.

In the drawings: Figure 1 is a cross-section through the lower end of a support for a vane dew condenser and illustrates in cross-section a subterranean camouflet chamber, Figure 2 is a side view of a vane type condenser adapted to be rotatably mounted on the support of Figure 1, Figure 3 shows in cross-section the upper end of the vane type condenser and shows the connection between the condenser and the support, Figure 4 is a cross-section through the vane type condenser on the line A-A of Figure 3, Figure 5 is a cross-section through the lower end of the vane type condenser of Figure 2 and shows the swivel bearing for supporting the lower end of the condenser vane, Figure 6 is a cross-section on the line B-B in Figure 3.

Figure 7 is a cross-section through the line C-C of Figure 5, Figure 8 is a cross-section through the line D-D also of Figure 5, Figure 9 is a side view in cross-section of an alternative form of condenser in the form of an inverted cone, Figure 10 is a plan view from above of the conical condensing surface of the device shown in Figure 9. and Figure 11 is a cross-section of a dew condenser and underground growth initiation chamber, which may be constructed from pottery.

Referring first of all to the embodiment shown in Figures 1 to 8 a subterranean chamber 10 is formed by means of an explosive charge which is introduced into the ground at the lower end of a tube 12 having an expendable drilling head or nose cone 14. After detonation of the explosive charge, the resulting explosion produces a substantially spherical chamber known as a camouflet chamber 10 and the tube 12 is partially withdrawn to the position shown in Figure 1.

Although in some applications it would be possible to use the chamber without a liner, it is preferable to provide a liner or sac within the chamber for containing the condensate and to this end a sac formed from sheet plastics material is introduced into the camouflet chamber through the tube 12 in a furled condition. The sac can be expanded once introduced into the chamber 10 so as to form a lining bag or sac 16.

The sac includes a long narrow neck 18 the upper end of which receives the condensate and is typically sealed to the condensate collector to prevent loss of moisture.

The tube 18 is typically of metal or hard plastics material.

The section of the tube 12 which extends above the level of the ground consitutes a support for one or more condensing surfaces as will hereinafter be described and although not shown, support means may be located around the protruding tube 12 to contain the lateral forces which will be exerted on the tube 12 due to wind etc.

acting on the condensing surface or surfaces and typically a tripod type support may be situated around the protruding tube so as to dig into the surface of the soil around the protruding tube and additionally prevent the tube from being depressed down into the soil under the weight of the condensing surfaces.

Referring now to Figure 2, a preferred form of condensing surface comprises a triangular sheet of low density metal such as aluminium supported by a radial arm 20 pivotably joined to the upper end of an extension of the tube 12 generally designated 22 and having its lower apex supported by a swivel bearing generally designated 24 hereinafter described in more detail. The triangular sheet generally designated 26 may be duplicated to form a double condenser and in fact any number of such triangular sheets may be located angularly around the supporting core 22 but in practice two sheets as will hereinafter be described are found to be sufficient.

The design allows the triangular vane assembly to rotate about the vertical axis of the tubular support and the result is that the vane will align with the wind direction so as to reduce the area of contact presented broadside to the wind. In sandy and semidesert conditions this will reduce the buildup of sand and other airborne soil particles both on the surface of the vane and against the structure generally which would reduce its effectiveness very rapidly.

Figure 3 shows the preferred method for attaching the radial arm 20 and therefore the upper end of the triangular vane assembly to the supporting tube 22. The bearing comprises an inverted cup 28 attached to or formed integrally with the radial arm 20, the cup having an outer cylindrical sleeve 30 and an inner cylindrical sleeve of reduced diameter 32 for defining an annular space into which the upper end of the tube 22 can fit.

An annular ring of Nylon (registered trade mark) or similar hard-wearing bearing material is fitted over the upper end of the tube 22 to provide a bearing surface on which the inside of the cup member 28 can rest and rotate. This annular ring is generally designated 29.

Figure 4 is a cross-section on the line A-A of Figure 3 and shows the two triangular vanes 26 (visible in Figure 2) and 34 (which is hidden from view in Figure 2 by the other triangular vane 26). The two trianguler vanes or sheets 26 and 24 are riveted along their upper edges to a pair of parallel flanges 36 and 38 which form part of the radial arm 20 and which are joined at the bearing end by means of a bridge piece 40 (shown in Figure 3) and the remote end 42 (see Figure 2) by a similar bridge piece. Along the majority of the length of the arm 20 the two flanges 36 and 38 are separated by the gap 42' shown in Figure 4.

Figure 5 shows the detail of the support for the lower end of the triangular vane assembly. The tubular support 22 is formed in two parts an upper tube 44 and a lower tube 46 which are joined by an inner tube 48 which is threaded into the lower end of the upper tube 44 and the upper end of the lower tube 46.

The inner tubular member 48 includes an annular shoulder 50 intermediate its two ends which prevents the inner tubular member 48 from being screwed into the lower tube 46 by more than a given amount. In addition the shoulder 50 includes an annular lip 52 the upper circular periphery of which is covered by an annular ring 54 of hardwearing bearing material such as Nylon (registered trade mark) and a cylindrical sleeve 56 rests on the ring of bearing material 54 and includes an inner cylindrical protrusion 58 for radially locating the sleeve axially about the cylindrical assembly of the tubes 44, 46 etc. by bearing against an inner surface of the ring of bearing material 54.

The upper end of the sleeve 56 is formed with a radially extending inwardly directed lip 60 which is cut away at 62 to allow condensate to flow into the annular space between the sleeve 56 and the tube 40.

The condensate can drain past the lower end of the tube 44 between the inner surface of the sleeve 56 and the tube into the annular cavity between the lower end of the tube 44 and sleeve 56 and the annular shoulder 50. This annular space is generally designated 64. Ports shown at 66, 68 and 70 communicate between the annular space 64 and the interior of the tube 48 and thus the interior of the tubular assembly generally.

Under sandy conditions, the condensate will cause grains of sand to enter the annular space 64 and to this end one or more radial vanes 72 are provided on the inside of the lower end of the annular ring 58 to serve as sand ploughs for dislodging any sand which builds up within the annular cavity 64 and cause the sand to be discharged through the ports 66, 68, 70 etc. to drain down into the reservoir with the condensate.

It will be appreciated that although this will over a period of time reduce the volume of the reservoir available for storing water, by providing a sac of appropriate dimensions at the outset, and reducing the resistance to wind flow and therefore the catchment of sand to the minimum, the life expectancy of the complete apparatus can be made as long as is required and certanly a number of years before the reservoir becomes too clogged with sand to be useful.

It will also be appreciated that where the water is to be used for irrigation purposes, it is of relative unimportance that the sac shall become largely filled with sand since water entering the sac reservoir will simply filter through the sand and into the subsoil through the porous wall or apertures in the wall of the sac as will be described.

Figure 6 is a cross-section on the line B-B in Figure 4. This shows two triangular condenser vanes 34 and 26 which are reinforced along their upper edges and joined to the flanges 36 and 38 respectvely and the bridging member 40 which is in the form of an outer inverted cup is shown in section in Figure 6. This latter surrounds the outer cylindrical wall 30 of the cup 28 and the inner cylindrical wall is shown at 32. The tube 22 is shown sandwiched between the inner and outer cylindrical walls 30 and 32.

The sloping edge of the triangular vanes 26 and 34 is reinforced in a similar way to the reinforcement applied along the upper radial edges of the vanes and this reinforcement is best seen by referring to Figures 5, 7 and 8. The reinforcement comprises in each case a flange 74 and 76 which are secured by riveting or otherwise to the edges of the triangular plates 34 and 26 respectively. The flanges are formed integrally with channel sections 78 and 80 respectively which constitute drip trays and collection channels for collecting the condensate from the surface of the vanes 26 and 34 and conveying same to the annular space 82 within the circular sleeve 56 via the cutaway region 62 of the upper end of the sleeve 56.

Typically the tube 44 is formed from Duralumin and the triangular vanes 26 and 34 are formed from aluminium sheet.

The tube 48 is formed fron noncorrodable metal and the tube 46 is formed from non-corrodable metal or rigid plastics material.

Referring once again to Figure 5, it will be seen that the neck of the tubular neck of the reservoir sac is trapped between the lower end of the tube 48 and the annular shoulder 84 formed internally on the tube 46. Prefer ably the neck is reinforced typically by means of a metal ring or rigid plastics ring.

Although not shown a ring of electrically insulating material may be provided in the tube 46 (where the latter is formed from metal) so that there is no electrical connection between the inner tube 48 and remainder of the structure and earth. In this way the build up of static electricity on the assembly due to the continual passage of wind and sand particles etc. over the surface of the vane can go on unhindered and high electrostatic charges can be built up on the surface which will tend to assist in the condensing action.

It will be appreciated that where the lower tube 46 is formed from a rigid plastics material or where the tube 48 is formed from a plastics material no insulating ring electrically separating the upper section of the unit from the lower section need be provided.

It will be further appreciated that the only part of the assembly which need be electrically insulated from the ground is the triangular vane assembly and to this end the vane assembly is already electrically insulated from the main stem of the support by means of the two annular bearings 29 and 54. To reduce any risk of arcing between the upper end of the cylindrical sleeve 56 and the tube 44, the internal surface of the unturned end 60 of the sleeve 56 may be insulated or may be itself formed from the insulating material such as a plastics material. Thus electrical insulation of the vane assembly can be simply achieved and although this means that the support stem remains at earth potential at least the vane can rise to high voltages due to electrostatic charging.

An alternative form of condenser is shown in Figures 9 and 10. In this arrangement the condensing surface 100 is generally conical and supports twelve radial fins which serve to increase the surface area exposed to airborne moisture for condensing same.

Condensing moisture migrates towards the apex of the inverted cone through which the condensate can drain into an inner tube 106 which fits in an outer tube 108 leading for example to an underground reservoir of the type shown in Figure 1 and which also serves as a support for the structure.

The fins are of two types. Two triangular plates 96 and 98 are slotted so that the one can fit into the other to form a cross member which divides the cone 100 into four quadrants. In each quadrant is located a pair of fins such as 102, 104 formed from a single triangular sheet which is folded in half to form the two fins and is then splayed apart so that the two halves subtend angle of approximately 30 so that when dropped into the quadrant it can be located so as to divide the quadrant into three equal sections.

The cone and fin condenser shown in Figures 9 and 10 may be employed in semi-desert and arid conditions where there is little risk of sandstorms and the like.

Figure 11 shows how the principle of the invention may be applied to local conditions in which only basic materials such as pottery are available. The system shown will allow a mesquite seed 110 to germinate in a subterranean chamber 112 which is formed from pottery. Two glazed dew ducts in the form of narrow interfitting covers 114, 116 connect with the interior of the chamber 112 and extend from the drainage outlet 118 of an internally glazed shallow V-section dish 120 also formed from pottery, and which serves as a dew condenser. An outlet 122 in the bottom of the chamber 112 allows the root system of the germinating plant to escape.

WHAT I CLAIM IS: 1. A dew condenser comprising a support, at least one condensing surface carried by the support on which airborne moisture will condense under appropriate climatic conditions, collector means associated with the condensing surface into which the condensate will drain and means for conveying the condensate to a reservoir, at least the condensing surface being electrically insulated from earth to permit electrostatic charge to build up on the condensing surface.

2. A dew condenser as claimed in claim 1 in which th condensing surface is either vertical or at an angle of less than 90" to the vertical so that condensate formed thereon will drain naturally under gravity into the collecting means.

3. A dew condenser as claimed in claim 1 or 2 in which the condensing surface is formed from a sheet of metal and the collecting means comprises a channel formed along at least one edge of the metal sheet into which condensate will drain off the surface of the sheet.

4. A dew condenser as claimed in claim 3 in which the metal sheet is flat and in the form of a vane which itself is rotatable about the support to take account of prevailing wind conditions so that the condensing surface is not normally presented broadside to the wind but aligns with the direction of the wind so as to present the minimum surface area and enhance use of the electrostatic effect of wind friction to attract moisture.

5. A dew condenser as claimed in claim 2 or 3 in which the condensing surface is an inverted conical surface, so that natural drainage will occur towards the apex of the cone both on the inside and outside surface thereof.

6. A dew condenser as claimed in claim

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ably the neck is reinforced typically by means of a metal ring or rigid plastics ring. Although not shown a ring of electrically insulating material may be provided in the tube 46 (where the latter is formed from metal) so that there is no electrical connection between the inner tube 48 and remainder of the structure and earth. In this way the build up of static electricity on the assembly due to the continual passage of wind and sand particles etc. over the surface of the vane can go on unhindered and high electrostatic charges can be built up on the surface which will tend to assist in the condensing action. It will be appreciated that where the lower tube 46 is formed from a rigid plastics material or where the tube 48 is formed from a plastics material no insulating ring electrically separating the upper section of the unit from the lower section need be provided. It will be further appreciated that the only part of the assembly which need be electrically insulated from the ground is the triangular vane assembly and to this end the vane assembly is already electrically insulated from the main stem of the support by means of the two annular bearings 29 and 54. To reduce any risk of arcing between the upper end of the cylindrical sleeve 56 and the tube 44, the internal surface of the unturned end 60 of the sleeve 56 may be insulated or may be itself formed from the insulating material such as a plastics material. Thus electrical insulation of the vane assembly can be simply achieved and although this means that the support stem remains at earth potential at least the vane can rise to high voltages due to electrostatic charging. An alternative form of condenser is shown in Figures 9 and 10. In this arrangement the condensing surface 100 is generally conical and supports twelve radial fins which serve to increase the surface area exposed to airborne moisture for condensing same. Condensing moisture migrates towards the apex of the inverted cone through which the condensate can drain into an inner tube 106 which fits in an outer tube 108 leading for example to an underground reservoir of the type shown in Figure 1 and which also serves as a support for the structure. The fins are of two types. Two triangular plates 96 and 98 are slotted so that the one can fit into the other to form a cross member which divides the cone 100 into four quadrants. In each quadrant is located a pair of fins such as 102, 104 formed from a single triangular sheet which is folded in half to form the two fins and is then splayed apart so that the two halves subtend angle of approximately 30 so that when dropped into the quadrant it can be located so as to divide the quadrant into three equal sections. The cone and fin condenser shown in Figures 9 and 10 may be employed in semi-desert and arid conditions where there is little risk of sandstorms and the like. Figure 11 shows how the principle of the invention may be applied to local conditions in which only basic materials such as pottery are available. The system shown will allow a mesquite seed 110 to germinate in a subterranean chamber 112 which is formed from pottery. Two glazed dew ducts in the form of narrow interfitting covers 114, 116 connect with the interior of the chamber 112 and extend from the drainage outlet 118 of an internally glazed shallow V-section dish 120 also formed from pottery, and which serves as a dew condenser. An outlet 122 in the bottom of the chamber 112 allows the root system of the germinating plant to escape. WHAT I CLAIM IS:

1. A dew condenser comprising a support, at least one condensing surface carried by the support on which airborne moisture will condense under appropriate climatic conditions, collector means associated with the condensing surface into which the condensate will drain and means for conveying the condensate to a reservoir, at least the condensing surface being electrically insulated from earth to permit electrostatic charge to build up on the condensing surface.

6. A dew condenser as claimed in claim

5 in which the inverted conical surface is formed from a plurality of triangular segments.

7. A dew condenser as claimed in claim 5 or 6 in which the surface area is increased by providing fins on the surface of the cone internally or externally or both.

8. A dew condenser as claimed in any of the preceding claims in which the reservoir is situated below ground level and pipe means serves to convey condensate from the collector means to the reservoir.

9. A dew condenser as claimed in any of the preceding claims in which the support serves a dual purpose and at least in part constitutes a tube through which condensate can flow to the reservoir.

10. A dew condenser as claimed in any of the preceding claims in which the reservoir comprises a sac of plastics material having an opening through which condensate can pass which is sealed to the lower end of a tube leading from the collector means and the sac is situated in a subterranean chamber.

11. A dew condenser as claimed in any of the preceding claims further comprising means for tapping the water contained within the reservoir and drawing off same.

12. A dew condenser as claimed in any of the preceding claims in which the reservoir is below ground level and is formed at least in part from a porous material so that water collected therein can seep through the wall to the exterior and provide a source of moisture below the ground level which can be tapped by roots of plants situated within an appropriate distance from the underground chamber.

13. A dew condenser as claimed in any of claims 1 to 11 in which the reservoir is perforated to allow water to drain out to provide irrigation.

14. A dew condenser as claimed in claim 13 further comprising a closure member which can be operated remotely to open and close the aperture whereby water collected within the reservoir can be retained therein and discharged for irrigation purposes into the subsoil in a controlled manner.

15. A dew condenser as claimed in claim 14 in which the closure device operates in such a way as to partially or completely close the aperture so that by adjusting the position of the closure device between the fully open and fully closed positions, varying degrees of flow rate can be obtained.

16. A dew condenser as claimed in claim 1 or 2 in which at least the condensing surface is formed from pottery.

17. A dew condenser as claimed in any of the preceding claims when situated close to a shrub or tree of the type which forms a large root system for collecting water before creating much if any top structure whereby the soil is bound together by the root system of the plant and erosion around the plant and the immediate vicinity is reduced.

18. A dew condenser and plant as claimed in claim 17 in which the plant comprises the mesquite tree.

19. Dew condensers constructed arranged and adapted to operate substantially as herein described with reference to and as illustrated in the accompanying drawings.