Description
Resonating Magnetic Fluid Conditioning Apparatus and Method
Cross-Reference to Related Application
This application is a continuation-in-part of Application Serial No. 341,062 filed January 20, 1982.
Technical Field
This invention relates generally to apparatus and methods of conditioning fluid flow in a conduit so as to prevent and reduce the build up of mineral deposits on the inner walls of the conduit. More particularly, the invention improves upon those devices which condition by impression of alternating magnetic fields upon the fluid.
Mineral deposits known as "scale", usually consist of carbonate, silicate, or sulfate salts of calcium or mag¬ nesium. When deposited on interior surfaces of pipes, turbine, or boiler equipments, they tend to reduce heat transfer and fluid flow, resulting in increased energy costs and maintainance actions.
Background Art
Numerous magnetic devices or systems have been proposed for preventing the reduction of mineral build up in water lines. Early art dates to at least 1865, when Parry in U.S. Patent 50,773, described conditioning of water with a fixed magnetic field. In Belgian Patent No. 460,560 and in U.S. Patent 2,596,743 Vermeiren noted that improved efficiency could be obtained by use of a reversing magnetic field produced by an alternating current supply driving an electromagnet. In U.S. Patent 2,652,925 Vermeiren replaced the time variation of an alternating current generated field with a spacial alterna¬ tion of the field direction. This was obtained by placing, like poles of the magnets adjacent to each other. Fluid was thus subjected to a series of reversals of magnetic field direct
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as it passed through a conduit. Improvements in this basic art have been generally directed to methods of increasing the magnitude of fluid exposure to higher flux density amplitudes.
The relationship of repetitive alternating field exposure to the velocity of the fluid in the conduit was found by Kron- enberg, and disclosed in U.S. Patent No. 4,428,837.
He noted that at a given field separation spacing, effic¬ iency of scale reduction improved at a particular fluid veloc¬ ity. Variation of spacing or of fluid velocity about this point reduced the scale reduction process. He thus disclosed a spacial resonance phenomenon which could be adjusted by posi¬ tioning of the magnetic field generating devices along the axis of the conduit.
Even if optimized as noted above, scale reduction effic¬ iency can drop significantly, typically by more than 50%, when the flow rate increases or decreases by half from the narrow optimum treatment range. Some drop is also observed when mineral content and structure of the liquid changes. In cer¬ tain Metropolitan water districts, for instance, water mineral characteristics change due to seasons. Mineral content also changes with man-made blending of available water, from well, river and reservoir sources, each of which can change with seasonal rain water content. Thus magnetic treatment range, even when optimized for onevelocity can be too narrow to ac- comodate normal variations of flow velocities within the fluid conduit and to changes in fluid structure and mineral content. In addition, early devices were physically constructed such that magnetic field spacing could not be readily varied to accomodate these changes once a system had been installed.
Disclosure of Invention
The invention disclosed here overcomes the above limita¬ tions by combining a. series of individual magnetic treatment sections, called frequency modules, each of which has been separately optimized in accordance with the above principles. Thus, indi-vidual sections, which have had their magnetic ele¬ ments spaced so as to optimize conditioning at a particular
flow rate, are cascaded in order to broaden the range of fluid velocities effectively treated. Spacing between each frequency module is selected to enhance coupling and to avoid destructive coupling. In effect, by analogy to electrical filter frequency tuning, such groups of multiple frequency sections, can be considered as a spacial stagger-tuned device over a broad range of fluid velocities. Indeed, it is believed that the physical phenomena exhibited results from harmonic excitiation, by the spacial field-reversing frequencies, of molecular oscillations within the fluid which tend to disassociate the mineral . mole¬ cules from their ionic bonding and produce a soft precipitate.
My invention is arranged so that the group of individual frequency modules are physically combined axially into a unit, which for convenience, is referred to as a generator pack. A generator pack will contain an even number of frequency modules, each set for maximum efficiency at a particular spacial frequency or fluid velocity. The number of modules cascaded will depend upon the broadness of the range of fre¬ quencies or fluid velocities expected to be treated.
In the preferred embodiment of this invention the genera¬ tor pack will be covered and supported adjacent the outside of a fluid conduit by means of an attachment chassis. This ar- rangment provides the advantages of minimum fluid flow obstruc¬ tion and maximum ease of installation and replacement. When changes in fluid flow or mineral content so dictate, the vel¬ ocity range may be quickly tailored by insertion of a new generator pack.
Although my device is not designed to be a magnetic par¬ ticle separator, it will attract such particles over a period of time. The particles will collect on the inside of the con¬ duit wall and will tend to shunt the magnets. With my portable outside attachment means, the device may be easily and rapidly loosened and slid upstream on the conduit.
In an alternate embodiment of this invention, the magnetic treatment sections of the generator pack may be arranged co- axially about the fluid conduit. Since such configurations can result in increased flux density with given volumn constraints,
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they would be preferred in those applications where ease of removal or returning is not necessary.
Brief Description of Drawings
The details of my invention will be described in connec¬ tion with the accompanying drawings, in which:
Figure 1 is an isometric view of the cover used to protect the generator pack.
Figure 2 is an isometric view of the generator pack re¬ moved from the cover of Figure 1.
Figure 3 is an isometric view of the mounting chassis structure with attached strap type fasteners, positioned over the enclosed generator pack.
Figure 4 is an end cross section of our assembled inven¬ tion in working engagement with a fluid conduit work piece.
Figure 5 is an end cross section of one unit attached to a cluster of three pipes by means of a strap-type fastener.
Figure 6 presents graphical data showing the variation in magnetic field strength under a set of variable spaced poles.
Figure 7 presents graphical data showing the variation in water conditioning efficiency with velocity in the conduit.
Figure 8 shows a seri.es of partial side cross-sectioned views of alternate generator pack embodiments. Best Mode for Carrying Out the Invention
Referring to Figure 1 of the drawings, a set of individual frequency modules are perspectively shown arranged into a gen¬ erator pack. Each individual module contains a bar magnet 1, side face magnetized and made preferrably of a true permanent magnet material such as strontium ferrite. Adjacent to each side face of magnet 1 are flux collector plates 2. These plates make close contact with each pole face, and can typically be made of milled steel. The edges of each plate 2 are partial¬ ly beveled to reduce the edge thickness by approximately two- thirds so as to better concentrate the magnetic flux lines into increased flux density for communicating across the fluid conduit.
The magnets are spaced .apart by a series of non-magnetic
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flux separators, shown as 3, 4, 5, 6, and 7 in Figure 2. These are depicted as increasing in width from 3 to 7. When so spaced, lower velocity fluid will be more effectively treated at the smaller spaced end of the device.
Although each magnet 1 is shown in Figure 2 as being of equal width, they may also be arranged in staggered thickness or field strength fashion as a further aid to obtaining the desired spacial frequencies.
The above set of frequency modules are assembled into a thin walled non-ferrous case 10, shown in Figure 1. The as¬ sembly may be rigidly sealed with end cap 9, into a permanent unit, or fitted with a removable seal for field replacement or cleaning .
Figure 3 shows chassis structure 11 which is used to support the case 10 of the generator pack firmly against the fluid conduit. Attachment means, such as the strap 12, is used to wrap around and secure both the case and the conduit. Figure 4 shows generator pack 10, so held in place within chassis 11. A hook and eye attachment 12, such as Velcro, is used to hold the chasis and the generator firmly against the conduit 13 containing fluid 14.
Figure 5 presents an alternate arrangement in which a plurality of conduits can be serviced by one magnetic conditio¬ ner. Three conduits 13 are maintained in direct contact with case 10 without the chassis by attachment strap 12. The number of conduits so serviced is thus limited only by the number sides placed on the magnetic modules and the case.
The physical phenomenon underlying this invention is indi¬ cated by the measurement data of Figure 6. Field strength in Gauss has been measured under each of a set of magnetic poles at the tapered collector plate edges. The spacing between the magnetic modules has been varied and it will be noted that a spacial frequency is developed in flux amplitude. Separation distances are shown which result in a constructive broadening of the flux peaking.
The resulting performance curve associated with the flux-distance curve of Figure 6 is indicated in Figure 7. Here
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the conditioning efficiency of the device is indicated by measurement of the percent reduction in calcite crystals re¬ maining in a drop sample of water. The independent variable in Figure 7 is the velocity of water flow through the conduit. It will be noted that the efficiency curve tends to follow the broadened composite curve of the individual units in keeping with the flux-distance variation of Figure 6. Pro¬ per selection of spacing between the magnetic modules therefore has improved the efficiency of mineral removal over a broad range of fluid velocities.
Figure 8 A through F present a series of cross-sections of alternate coaxial embodiments arranged for comparison con¬ venience with a top half cross-section of the external embodi¬ ment, 8G.
Figure 8A shows a basic harmonic treatment device composed of six magnetic circuit elements (1,2) separated by five sep¬ arators (3), all placed concentrically around a cylindrical tube which contains in its center a coaxial concentrator core (15). All magnetic units have similar dimensions, and all separators are of approximate equal length. The unit is maxi¬ mally effective at one specific flow rate, but its effectivity can be improved by changing the length and number of magnetic units.
Figure 8B shows a combination of two of the basic devices of figure 8A separated by a spacing element called a harmonic bridge, 16. A plurality of such frequency or impact sections can be arranged to maintain high treatment effectively over a wide range of variable flow rates.
In Figure 8C, the embodiment utilizes similar sized magne¬ tic units but with different sized spacers. The variable flow range can thus be covered with fewer magnets where space con¬ servation is important.
Figure 8D shows a device with equally sized separators but differenly dimensioned magnetic circuit elements. This pro¬ vides for a variation of magnetic flux densities which can be useful in cases where the specific mineral content of the liquid presents unusual conditions.
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Figure 8E presents the most hardware effective case in which both the magnet and separators are dimensionally varied.
The arrangement of figure 8F is especially useful with smaller flow rates through more narrow conduits. The smaller diameters involved permit sufficient magnetic field strength without the aid of the concentrator core, 15 of Figure 8A.
Industrial Applicability
This invention has utility in any liquid consuming indus¬ try, and has special application to those industries that use water as a motive power. In the former class, older plants with internal water line corrosion often find that replacement of pipe sections is impossible since wrenching of the pipe produces further deterioration. The externally placed device in accordance with the best mode of our invention can thus be used to reduce the internal scale build-up without physical pipe line disturbance.
In addition to pipe conduits, water chamber devices such as boilers and heat exchangers will benefit from less frequent fouling .
In those industries using water motive power, such as electrical power generators, the life of apparatus such as turbines are often governed by impeller corrosion. Prevention of scale build-up results in lower energy loss and improved flow in addition to longer life.
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