GB2132997A

GB2132997A - Apparatus for and method of treating water and use of the treated water in plant irrigation

Info

Publication number: GB2132997A
Application number: GB08233283A
Authority: GB
Inventors: Oliver Charles Langdale
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-11-22
Filing date: 1982-11-22
Publication date: 1984-07-18

Abstract

An apparatus for treating water comprises:- a closed water conduit; a flow straightener for producing a laminar flow of water downstream thereof in the conduit; a venturi device downstream of the flow straightener for accelerating the laminar flow of water; and means for applying to the accelerated flow of water a magnetic field, transverse to the direction of flow of the water, located within said conduit, wherein the product of the velocity of the accelerated water (in metres per second) and the magnetic field strength (in Teslas) is at least 8, and a method of treating water by applying a magnetic field thereto. Water treated in the apparatus or by the method is used to irrigate plants, thereby to enhance plant growth.

Description

SPECIFICATION Apparatus for and method of treating water and use of the treated water in plant irrigation The present invention relates to an apparatus for and a method of treating water to make the water more suitable for irrigating plants.

The invention also includes the use of water treated by the apparatus or method in the irrigation of plants, whereby plant growth is enhanced.

It is known that, although water is essential for plant growth, it is possible to inhibit plant growth or, in some cases, kill plants by applying too much water to them. Many factors may contribute to the deleterious effects of over-watering of plants. It is believed that the following factors are of particular importance.

Water generally contains a substantial amount of mineral matter, normally in the form of salts dissolved out of the rocks through which the water either percolates into a well or flows from the source. When the water is applied to or around a plant, the water evaporates or is absorbed, leaving the mineral matter deposited on the plant or on the earth around it. The mineral water on the plant may interfere with the plant's metabolism and therefore have a deleterious effect on it.

The mineral matter on the earth may cause the earth to become less porous, thus making it difficult for water to penetrate into the earth to the roots of the plant. It is known that most of a plant's water is absorbed through its roots and therefore if the water cannot penetrate to the roots the plant will be adversely affected, even if there is a pool of water on the surface of the earth around it.

In general water is acidic, either due to the presence of minerals in the water or due to the emissions from the combustion of fossil fuels, which are absorbed into atmospheric water vapour and precipitated as 'acid rain'. A large number of plants are adversely affected by acid water and therefore application of large quantities of acid water, either by irrigation or by rainfall will have a deleterious effect on these plants.

It has been observed that plants, even if they have been subject to overwatering, generally appear to improve in condition after they have been watered by rain falling during a thunderstorm, even though they may deteriorate in condition after they have been watered by an ordinary shower or rain.

The present inventor has caried out investigations in order to discover the reason why plant growth is enhanced by rain falling during a thunderstorm, but not by ordinary rainfall, and to find a way in which the effect may be achieved in the absence of a thunderstorm.

It is accordingly an object of the present invention to provide an apparatus for and method of treating water to make the water more suitable for irrigating plants and to use the treated water to irrigate plants thereby to enhance their growth.

According to a first aspect of the present invention, there is provided an apparatus for treating water comprising: a closed water conduit a flow straightener for producing a laminar flow of water downstream thereof in the conduit; a venturi device downstream of the flow straightener for accelerating the laminar flow of water; and means for applying to the accelerated flow of water a magnetic field, transverse to the direction of flow of the water, located within said conduit, wherein the product of the velocity of the accelerated water (in metres per second) and the magnetic field strength (in Tesla) is at least 8.

According to a second aspect of the present invention, there is provided a method of treating water comprising: producing a laminar flow of water in a conduit; accelerating the laminar flow of water; and applying a magnetic field to the accelerated flow of water transverse to the direction of flow of the water, wherein the product of the velocity of the accelerated water (in metres per second) and the magnetic field strength (in Tesla) is at least 8.

The water may be conveyed from the conduit in an open channel such as a gutter or irrigation channel, but is preferably conveyed from the conduit in a closed pipe.

The conduit and pipe are preferably circular in cross-section and may be made from nonmagnetic or plastics materials.

In general water pumps are of the centrifugal type and impart to the water pumped out of it a swirling motion such that as the water travels along the conduit it follows a spiral path. If such a pump is used, it will be necessary to provide a separate flow straightener (which is also known as a laminar flow divider). These are knonw in the art.

A preferred form of laminar flow divider comprises an elongated member having a cross-shaped cross-section which divides the flow of water in the conduit into four equal parts and prevents flow of water through the centre of the conduit. The flow divider may be made from two intersecting plates or formed as a single piece of material, for instance in the form of a plastics extrusion.

Advantageously the flow divider produces a laminar flow in which the velocity distribution in the direction transverse to the flow direction is uniform.

Alternatively, the flow straightener may comprise a positive displacement pump which will generally cause the water it is pumping to flow in laminar fashion, or may assist such a positive displacement pump in providing such a laminar flow.

The flow straightener may also comprise the conduit itself, especially where the conduit is a pipe. It is known that, even if the pump imparts a swirling motion to the water, after travelling a certain distance, the water begins to flow in a laminar fashion. The disadvantage of this is that the velocity distribution is very uneven, the water at the centre of pipe travelling considerably faster than the water at the edge of the pipe. Generally, there is a layer of water at the edge of the pipe which is hardly moving at all due to the frictional effects of the pipe.

It will be appreciated that the use of the conduit as a flow straightener or the use of a flow straightener in the pipe may reduce the velocity of the flow of water to such an extent that it can no longer be suitably accelerated for treatment by the magnetic field. A skilled person will therefore appreciate that the water should be pumped at such a rate that its velocity after passing the flow straightener is sufficient for it to be suitably accelerated.

Venturi devices for accelerating a flow of water/or any other fluid are known in the art and any of these may be used.

A venturi device operates by reducing the cross-sectional area of the conduit so that the water flowing in the conduit has to travel faster through this region in order to maintain the same volume flow through the pipe. Thus the venturi device may be formed by reducing the diameter of the pipe or by inserting a member in the pipe to obstruct part of it.

The means for applying a magnetic field preferably comprises at least one pair of permanent magnets fixed such that a north pole of one magnet is held in spaced apart relationship with the south pole of the other. Conveniently there are at least two pairs of magnets.

Alternatively the field may be applied electromagnetically for instance by use of at least one magnetic coil. The coils may be supplied directly from a DC source or from an AC source via a rectifier circuit, for instance a diode rectifier circuit. Preferably the or each coil is located around a bar of magnetisable material.

Advantageously, magnetic pole pieces held on the bars or permanent magnets, located in the conduit, and shaped to act as the venturi device are used.

In a preferred embodiment, wherein the flow straightener is a cross-shaped member, the means for applying the magnetic field comprises four quadrant shaped magnetic pole pieces held in spaced apart relationship to define therebetween a flow channel having a cross-shaped cross-section, the flow channel being offset at about 45 to the flow straightener and the poles being alternately north and south poles.

Advantageously, there are two means for applying magnetic fields to the accelerated flow of water. In a preferred embodiment, each means comprises a four quadrant structure as set out above and the north and south poles in one structure are connected by a bar magnet, which may be a permanent magnet or a bar of magnetisable material surrounded by a coil, to a south or north respectively pole in the other structure. Preferably each bar magnet is circular in cross-section, although bar magnets of rectangular, hexagonal, octagonal, etc, cross-section may also be used.

Conveniently a second flow straightener is located in the conduit downstream of the or each means for applying the magnetic field.

Advantageously, where permanent magnets are used, they are held spaced apart relationship by being fixed onto the flow straightener(s).

Preferably, the magnetic field applied to the accelerated flow of water is about 1.25 Tesla and the accelerated water has a velocity of about 9 metres per second. However, it will be possible to vary these values as necessary as long as the product of them does not fall below the value given above.

A third aspect of the invention comprises the use of water treated in the apparatus or by the method described in the irrigation of plants, whereby plant growth is enhanced.

The present Inventor believes that the following theory can be used to explain why water treated in the apparatus or by the method of the present invention enhances plant growth. However, the Inventor does not wish the invention, the scope of which is set out in the claims appended hereto, to be limited to this theory.

The Inventor believes that rain falling during a thunderstorm enhances plant growth because its properties have been altered by the effect of the static electricity discharges, in the form of lightning, which occur during thunderstorms. The Inventor believes that the treatment of water according to the invention mimics the effects of these static electricity discharges.

Water, especially if it contains mineral matter in ionised form, is a conductor of electricity. It is known that if a conductor is moved across a magnetic field an electric current is induced in the conductor.-Thus, as the water flows through the magnetic field, it is believed that a current is induced therein and that this current affects the properties of the water in a similar manner to the effects of the static electricity discharges on rainfall.

The inventor believes that the effect of the magnetic field on the water changes the ionisation state of the water, increases its pH and affects the way in which the mineral matter in the water crystalises. These changes enable the water to be more easily absorbed by the plant, assist in preventing the build up of mineral matter on the plant, and causes the mineral matter to be deposited on the ground in such a manner that it does not prevent the water from reaching the roots of the plant to the same extent that untreated water does.

Moreover, the Inventor believes that the surface tension properties of the water are affected such that the water is able more easily to penetrate the ground and reach the roots of the plants. The treatment of the water therefore reduces the deleterious effects of watering.

Two embodiments of apparatus according to the present invention are now described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side view of a first embodiment of the apparatus with parts cut away for the sake of clarity, Figure 2 is a view along line 2-2 of Fig. 1; and Figure 3 is a similar view to Fig. 1 of a second embodiment of the apparatus with electrical connections shown schematically.

Referring now to Figs. 1 and 2 of the drawings, the first embodiment of the apparatus comprises a pipe (10) which is connected to a pump (not shown) for driving water from left to right as shown in Fig. 1.

A first flow divider (12), comprising a pair of intersecting plates (14, 1 6), is located in the pipe (10) and is fixed in position by welding to the pipe (10). Each plate (14, 16) has in it a slot extending half way along the centre line from one end for co-operation with the slot on the other plate. The flow divider (12) has a cross-shaped cross-section and is constructed of non-magnetic stainless steel.

A quadrant shaped pole piece (18, 20, 22, 24) of magnetic material, such as iron, is welded onto the downstream end of each of the arms of the flow divider (12). The poles (18, 20, 22, 24) are fixed onto the flow divider (12) by means of slots and are held in spaced apart relationship so as to define a cross-shaped flow channel (26) therebetween.

A well (28, 30, 32, 34) is formed in the face of each of the poles (1 8, 20, 22, 24 respectively) away from the flow divider (12) and has fixed therein one end of a rod shaped permanent magnet (38, 40, 42, 44 respectively).

The poles (18 and 22) are south poles and the ends of the permanent magnets (38 and 42) respectively therein are also south poles.

The poles (20 and 24) and end of magnets (40 and 44) therein are north poles. The poles are therefore of opposite polarity to those immediately adjacent each other. Thus a magnetic field is created across each arm of the flow channel (26) between adjacent north and south poles.

The magnets are of such a strength that the field strength between adjacent poles is 1.25 Tesla.

The cross-shaped flow channel (26) is of considerably smaller cross-sectional area than the pipe (10) and therefore acts as a venturi device for accelerating water flowing in the pipe (10).

The ends of the permanent magnets (38, 40, 42, 44) remote from the flow divider (12) are located in wells in further quadrants which in turn are held in spaced apart relationship by being welded onto a second flow divider (46) in the same manner as described above.

The second flow divider (46) is also welded onto the pipe (10). Thus the parts disposed in the pipe are symmetrical about a plane bisect ing the permanent magnets (38, 40, 42, 44) except that the poles at opposite ends of the permanent magnets must, of necessity, have opposite polarities.

Referring now to Fig. 3, there is shown a second embodiment of the apparatus which is similar in construction to the apparatus shown in Figs. 1 and 2. Like parts have therefore been given like reference numerals.

However, the magnetic pole pieces (18, 20, 22, 24) are connected to the pole pieces attached to the second flow divider by bars (58, 60, 62, 64) of magnetic material sur rounded by coils (68, 70, 72 74). The coils are connected to a DC supply of electrictiy (78) as shown such that bars 58 and 62 are magnetised in the opposite direction to bars 60 and 64 when current is passed through the the coils. The power supply circuit includes a rheostat 76 so that the current supplied to the coils can be varied as necessary to effect treatment of the water.

In use of either of these embodiments, the pump forces water from left to right in the tube. It is assumed that the water arriving at the upstream end of the first flow divider (12) is flowing turbulently. As it encounters the flow divider (12)the water is constrained to flow flow in laminar manner. At the downstream end of the flow divider (12) the water flowing in laminar fashion encounters the poles (18, 20, 22, 24) which act as a venturi device and accelerate the water into the flow channel 26.

As the accelerated water passes through the flow channel 26 the poles (18, 20, 22, 24) will exert a magnetic field transverse to the direction of flow of the water and will induce a current therein.

On exiting from the flow channel 26 the water decelerates and passes parallel to the magnets (38, 40, 42, 44) to the second set of poles. The water is then reaccelerated and again passes through a magnetic field transverse to the direction of water flow.

The water then flows past the second flow divider which maintains the laminar flow of water past the magnets.

In a typical example of the operation of the method, the water is pumped originally at a velocity of less than 2 metres per second, but is accelerated by the venturi effect of the poles to a velocity of about 9 metres per second.

The product of the field strength (in Teslas) and the velocity of the accelerated flows of water is therefore 11.25. It will be appreciated that this value is only typical and lower or higher values may be used provided that the value is at least 8.

The water exiting from the pipe is used to irrigate plants in order to enhance their growth. On a trial plot using a sample of 10,000 plants, it has been shown that plants irrigated with water which has been treated according to the present invention increase their weight over a given time period by at least 10% and in some cases up to 17%, more than plants raised in conventional manner.

Claims

1. Apparatus for treating water compris ing: - a closed water conduit; a flow straightener for producing a laminar flow of water downstream thereof in the conduit; a venturi device downstream of the flow straightener for accelerating the laminar flow of water; and means for applying to the accelerated flow of water a magnetic field transverse to the direction of flow of the water located within said conduit, wherein the product of the velocity of the accelerated water (in metres per second) and the magnetic field strength (in Tesla) is at least 8.

2. Apparatus according to claim 1, and including a closed pipe for conveying water from the conduit.

3. Apparatus according to claim 2, wherein the pipe is made from non-magnetic or plastics material.

4. Apparatus according to any one of claims 1 to 3, wherein the conduit is made from non-magnetic or plastics material.

5. Apparatus according to any one of claims 1 to 4, and including a centrifugal-type water pump for pumping water through the conduit.

6. Apparatus according to any one of claims 1 to 4, and including a positive-displacement-type water pump for pumping water through the conduit.

7. Apparatus according to claim 6, wherein the water pump comprises the flow straightener.

8. Apparatus according to claim 6 or claim 7, and including a laminar flow divider.

9. Apparatus according to any one of claims 1 to 5, wherein the flow straightener comprises a laminar flow divider.

10. Apparatus according to claim 8 or claim 9, wherein the laminar flow divider comprises an elongated member having a cross-shaped cross-section for dividing the flow of water in the conduit into four equal parts and preventing a flow of water through the centre of the conduit.

11. Apparatus according to claim 10, wherein the flow divider comprises a pair of intersecting plates.

12. Apparatus according to claim 10, wherein the flow divider comprises a single piece of material.

13. Apparatus according to claim 12, wherein the flow divider comprises a plastics extrusion.

14. Apparatus according to any one of claims 1 to 6, wherein the conduit itself comprises the flow straightener.

15. Apparatus according to any one of claims 1 to 14, wherein the means for applying the magnetic field comprises at least one pair of permanent magnets fixed such that a north pole of one magnet is held in spaced apart relationship with the south pole of the other.

16. Apparatus according to claim 15 and including at least two pairs of magnets.

17. Apparatus according to any one of claims 1 to 14, wherein the magnetic field is applied electromagnetically.

18. Apparatus according to claim 17, wherein the source of the magnetic field is at least one magnetic coil.

19. Apparatus according to claim 18, wherein the or each coil is powered by a DC or a rectified AC source.

20. Apparatus according to claim 18 or claim 19, wherein the or each coil is located around a bar of magnetisable material.

21. Apparatus according to claim 15 or claim 20, and including a magnetic pole piece held on the permanent magnets or bars of magnetisable material.

22. Apparatus according to claim 21, wherein the magnetic pole pieces are shaped to act as the venturi device.

23. Apparatus according to claim 21 or claim 22, when dependent on claim 10, wherein the pole pieces are quadrant shaped and define therebetween a cross-shaped flow channel, the flow channel being offset at about 45 to the flow straightener.

24. Apparatus according to any one of claims 1 to 23 and including two means for applying a magnetic field to the accelerator flow of water.

25. Apparatus according to any one of claims 1 to 24, and including a second flow straightener.

26. Apparatus according to claim 24 and 25, wherein the apparatus is symmetrical about a plane normal to the direction of flow.

27. Apparatus for treating water, substantially as hereinbefore described with reference to Figs. 1 and 2 or Fig. 3 of the accompany ing drawings.

28. A method of treating water comprising: producing a laminar flow of water in a conduit; accelerating the laminar flow of water; and applying a magnetic field to the accelerated flow of water transverse to the direction of flow of the water, wherein the product of the velocity of the accelerated water (in metres per second) and the magnetic field strength (in Tesla) is at least 8.

29. A method according to claim 28, wherein the velocity distribution in the laminar flow in the direction transverse to the flow direction is uniform.

30. A method of treating water, substantially as hereinbefore described with reference to Figs. 1 and 2 or Fig. 3 of the accompanying drawings.

31. Use of water treated in the apparatus according to any one of claims 1 to 27 or by the method of any one of claims 28 to 30, in the irrigation of plants, whereby plant growth is enhanced.