GB2285936A

GB2285936A - Magnetic treatment of fluids

Info

Publication number: GB2285936A
Application number: GB9401684A
Authority: GB
Inventors: Derek Alfred Woodhouse
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-01-28
Filing date: 1994-01-28
Publication date: 1995-08-02
Anticipated expiration: 2014-01-28
Also published as: GB9401684D0; GB2285936B

Abstract

A fluid e.g. water, is treated to induce coagulation of charged particles in the fluid by passing the fluid over alternate north and south magnetic poles 1 arranged in the direction of fluid flow while inducing turbulence of the fluid. An electrical current is thereby generated in the fluid within the alternating magnetic fields by magnetohydrodynamic effect which is operative to alter the electrical potential of the charged particles. This in turn induces coagulation of the particles without removing them from the fluid. Convoluted copper wire 8 of flattened or oval cross-section is provided. <IMAGE>

Description

Treatment of Fluids The invention relates to the treatment of fluids and is especially, but not exclusively, applicable to the treatment of water to prevent the accumulation of scale deposits in pipes, containers and the like.

It is known that scale forming particles in water subjected to magnetic treatment exhibit an increased tendency to remain in suspension in the water, thereby reducing the formation of scale deposits on the inside of pipes, vessels or the like through which the water passes. However the magentic field strength required to induce this phenomenon is high and it has proved difficult to generate sufficiently high magnetic fields to produce an appreciable effect without the use of extremely powerful and expensive magnets.

In Co-pending Application No. 9204847, there is disclosed a method and device for treating a fluid to induce coagulation of particles in which the fluid is passed through a magnetic field in contact with magnetic material through which the lines of magnetic force are transmitted through the fluid and which creates local acceleration and turbulence of the fluid. This results in generation of an electrical current by magnetohydrodynamic effect operative to alter the electrical potential of charged particles in the fluid and thereby induce coagulation.

In the embodiment described in Application No.

9204847, the magnets generating the magnetic force are disposed outside the conduit through which the fluid travels and the magnetic forces travel through the fluid assisted by the magnetic material located within the flow path. While this arrangement operates satisfactorily it is of relatively cumbersome and hence costly construction and it is an object of the present invention to provide an improved method and device of simpler and less costly construction.

The invention provides a method of treating a fluid to induce coagulation of charged particles in the fluid comprising passing the fluid over alternate north and south magnetic poles arranged in the direction of fluid flow while inducing turbulence of the fluid whereby to generate an electrical current therein within the alternating magnetic fields by magnetohydrodynamic effect operative to alter the electrical potential of said charged particles and thereby induce coagulation of the particles without removing them from the fluid.

The invention also provides a device for use in the treatment of a fluid to induce coagulation of particles in the fluid, the device comprising a casing through which the fluid flows in use, magnetic means within said casing producing alternate north and south magnetic poles arranged in the direction of fluid flow through the casing, and means for inducing turbulence of the fluid during its passage through the device.

Preferably said alternate north and south magnetic poles are produced by one or more multi-pole magnets disposed in the path of flow of the fluid. The magnets may advantageously be ferrite/ceramic or other forms of magnet which produce high magnetic field strengths per unit volume.

Preferably said means for inducing turbulence of the fluid comprises a body of material defining a plurality of passages therethrough, through which the fluid flows. The body of material may comprise coiled or twisted wire or like strandular material contained within the body of the device and surrounding and supporting the magnet or magnets. Preferably the wire is of flattened, oval or other non-circular cross-section. The body of material is preferably non-magnetic but may be magnetic material if desired.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a side elevation of one form of device according to the invention; Fig. 2 is an end view of the device shown in Fig.

1; Fig. 3 is a longitudinal cross-section through the device on the line III-III in Fig. 1; and Fig. 4 is a transverse cross-section through the device on the line IV-IV in Fig. 1.

Referring to the drawings, the device comprises a casing 1 having a cylindrical body portion 2 and an integral end member 3 provided with a through aperture 4 internally threaded at 4A. A separate cap member 5 is provided at the other end of the device and incorporates a through aperture 6 internally threaded at 6A. The cap member 5 may be fitted to the open end of the body member 2 and secured thereto by sonic welding or other suitable technique.

Within the body portion 2 a pair of multi-pole magnets 7 are supported in a body 8 of coiled, twisted or otherwise convoluted material. The magnets 7 each comprise multiple ferrite/ceramic magnets having alternate north and south poles arranged in the manner shown in the drawings. The two magnets are connected together by magnetic attraction at their adjacent ends and are arranged such that water flowing through the device from the inlet end 6 to the outlet end 4 passes successively through the magnetic field produced by the alternate north and south magnetic poles.

The body 8 of convoluted material preferably comprises copper wire and is arranged such that water entering the device through the inlet opening 6 passes around the magnets 7 through the body 8 before leaving the device by way of the outlet aperture 4. The wire is preferably of flattened or oval cross-section.

In assembling the device, the magnets 7 are placed in contact with one another and surrounded by the body 8 of convoluted copper wire. The end cap 5 is removed from the body member 2 and the unit comprising the magnets and wire 7,8 is inserted from the open end. The end cap 5 is then replaced and secured to the body 2 by sonic welding or other suitable technique.

The device operates by combined magnetic and magnetohydrodynamic effects. The purpose is to separate the electrical charges of the contaminant charged particles within the water or other fluid flowing through the device in order to produce an electrical current effective to cause a modification in the nuclear growth and coagulation of the charged particles within the fluid and render them less liable to attach themselves to pipe or other surfaces. The electrical balance of the particles is disturbed both by passage through the alternate magnetic field and by generation of an electrical current within the convoluted material by magnetohydrodynamic effect. The presence of the convoluted material causes local acceleration and turbulence of the water or other liquid passing through the device, thereby creating a localised vortex effect resulting in increased flow velocity.

In order for the device to operate satisfactorily, sufficient flow velocity is required to generate an electrical current by magnetohydrodynamic effect. This affects the electrical potential of particles of scale forming material within the water and induces coagulation of the particles in suspension. In turn this tendency of scale forming particles to coagulate in suspension rather than adhere to the walls of pipes or containers through which the water flows, reduces hard water scale deposits. The localised turbulence and acceleration produced within the magnetic field during passage of the water through the convoluted component 8 results in generation of the desired magnetohydrodynamic effect and enables the device to operate effectively at lower flow rates than would otherwise be required.

A particular advantage of the device is its ability to generate the magnetohydrodynamic effect necessary for effective operation when low flow rates are encountered in the system in which the device is fitted. Generally a minimum flow rate of at least six litres per second through a magnetic field is necessary to generate the magnetohydrodynamic mechanism. In practice it is not always possible to achieve or sustain this flow rate. Thus, for example, in domestic systems, operations such as filling a kettle or washing hands will not generate the magnetohydrodynamic mechanism and untreated water will enter the system. The present invention, by generating local turbulence and acceleration of the water during its passage through the magnetic field produced by the multi-pole magnets results in production of the magnetohydrodynamic effect at much lower overall flow rates than are generally required. In tests satisfactory operation has been achieved at inlet flow rates as low as two litres per minute, where hitherto flow rates of at least six litres per second have been required to generate the magnetohydrodynamic effect.

The degree of compaction and hence density of the convoluted wire element may vary dependent on the strength of the magnetic field and the rate of flow of water through the device. Typically the free volume of the convoluted wire element should be in the region of 70-90, but may in some circumstances be greater than 90, D. The free volume of the convoluted wire element is preferably approximately equal to the cross-sectional area of the pipe in which the device is fitted. This minimises restriction of water flow through the device produced by the presence of the element in the flow path.

In a typical example applied to a pipe of 15mm internal diameter, the device may be approximately i4cms long and Scms in diameter, the overall size of the magnets being approximately 8.25 x 2.5cms and the free volume of the convoluted body comprising 70-90g o. A device of this construction will operate satisfactorily at flow rates of about 2 litres per minute upwards.

Various modifications may be made without departing from the invention. For example, while it is preferred that the convoluted body consists of non-magnetic material, in some circumstances magnetic material may be employed. This is likely to be particularly the case where the number of magnetic poles is reduced compared with those provided in the embodiment. In principle the device would operate with a single magnet arranged longitudinally of the body member 2 such that the water flowed over each pole of the magnet in turn. In such circumstances the element 8 may advantageously be of magnetic material. It is preferred however that multi-pole magnets are employed to minimise the size of the device and that the convoluted component is of non-magnetic material.

Moreover while in the embodiment described a pair of multi-pole magnets are employed, one or more magnets presenting two or more alternate magnetic poles in the direction of flow through the device may be employed.

While in the embodiment coiled, twisted or otherwise convoluted wire or other strandular material is employed to induce turbulence of liquid flowing through the device, the wire may be replaced by a body of permeable or porous material, and need not be metallic. It could, for example, be formed from plastics material.

Alternatively, other means of inducing turbulence may be employed to produce the magnetohydrodynamic effect at low flow rates. While it is preferred that the convoluted wire or the like body is in contact with and supports the magnets, they may be spaced apart by a surrounding framework or the like by a coating applied to the surface of the magnets.

By virtue of the arrangement described, it is possible to induce coagulation of particles in suspension in water or other liquids by magnetic and magnetohydrodynamic means employing a device which is of simple construction and operation, which may be easily and cheaply produced and which operates at much lower flow rates than hitherto.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

Claims:

1. A method of treating a fluid to induce coagulation of charged particles in the fluid comprising passing the fluid over alternate north and south magnetic poles arranged in the direction of fluid flow while inducing turbulence of the fluid whereby to generate an electrical current therein within the alternating magnetic fields by magnetohydrodynamic effect operative to alter the electrical potential of said charged particles and thereby induce coagulation of the particles without removing them from the fluid.

2. A method according to claim 1 wherein said turbulence is induced by constraining the fluid to pass through a body of material defining a plurality of passages of convoluted form during passage of the fluid through said magnetic field.

3. A method according to claim 1 or 2 wherein said magnetic poles are designed to produce a high magnetic field strength per unit volume.

4. A method according to any of claims 1 to 3 wherein the overall rate of flow of the fluid is at least 2 litres per minute.

5. A method of treating a fluid substantially as hereinbefore described.

6. A device for use in the treatment of a fluid to induce coagulation of particles in the fluid, the device comprising a casing through which the fluid flows in use, magnetic means within said casing producing alternate north and south magnetic poles arranged in the direction of fluid flow through the casing, and means for inducing turbulence of the fluid during its passage through the device.

7. A device according to claim 6 wherein said alternate north and south magnetic poles are produced by multi-pole magnetic means disposed in the path of flow of the fluid.

8. A device according to claim 7 wherein said magnetic means is adapted to produce high magnetic field strengths per unit volume.

9. A device according to claim 8 wherein said magnetic means is a ferrite/ceramic magnet.

10. A device according to any of claims 6 to 9 wherein said means for inducing turbulence of the fluid comprises a body of material defining a plurality of passages therethrough, through which the fluid flows.

11. A device according to claim 10 wherein said body of material comprises convoluted strandular material contained within the body of the device and surrounding and supporting the magnet or magnets.

12. A device according to claim 11 wherein said strandular material comprises coiled or twisted wire.

13. A device according to claim 12 wherein said wire is of non-circular cross-section.

14. A device according to claim 13 wherein said wire is of flattened or oval cross-section.

15. A device according to claim 10 wherein said body of material is of permeable or porous construction.

16. A device according to claim 15 wherein said body of material is formed from plastics material.

17. A device according to any of claims 6 to 16 wherein said body of material is non-magnetic.

18. A device according to any of claims 6 to 17 wherein the free volume of the body of material is equal to or greater than 70.

19. A device according to any of claims 6 to 18 wherein the free volume of said body of material and the cross-sectional area of the pipe in which the device is fitted in use are selected to minimise restriction of fluid flow through the device in use.

20. A device for use in the treatment of a fluid to induce coagulation of particles in the fluid substantially as hereinbefore described with reference to the accompanying drawings.

21. Any novel subject matter or combination including novel subject matter disclosed in the foregoing specification or claims and/or shown in the drawings, whether or not within the scope of or relating to the same invention as any of the preceding claims.