JP2007537852A - Fluid filter - Google Patents

Abstract

  The fluid filter includes a filter housing having an inflow end (202) and an exhaust end (204), and a plurality of fibers (211) extending in the length direction of the housing and fixed at the inflow end. A bundle. The fibers are loaded by an electric or magnetic field to selectively block or allow passage of particles having a known load present in the fluid flowing to the discharge end. To force the removed particles out of the filter, the load applied to the fibers can be reversed so that the loaded particles can flow freely through the filter. The filter can also be used to control the sedimentation characteristics of particles in the fluid.

Description

  The present invention relates to a fluid filter, and although not limited thereto, it particularly relates to a high-pressure, high-throughput filter for removing solid substances from a liquid such as water.

  Patent Documents 1 and 2 disclose filters that use fibers to capture substances mixed in a medium. A similar device is disclosed in US Pat.

  The operating principle of the device of Patent Document 3 is schematically shown in FIGS. 1a and 1b. The filter 100 includes a filter housing 101 having an inflow end portion 102 and a discharge end portion 103. A plurality of parallel fibers extend along the length of the housing and are held in place by the support 106. A flexible water resistant membrane 104 surrounds the fibers.

  During filtration, the membrane 104 is pressurized as shown at 107 in FIG. 1 a, thereby clamping the fibers toward the internal pinch point 108. The material to be filtered is pushed through the filter in the direction indicated by the arrow. The filter can be cleaned by flushing the water by pressure release in the membrane and backwashing in the opposite direction of normal filtration flow.

  With respect to certain embodiments, US Pat. No. 6,099,077 discloses an inflatable balloon with fibers surrounding it, and when the balloon is inflated, the fibers are pressed against the inner peripheral surface of the filter housing.

While this type of filtration by fiber compression is useful for filtering out particles of one size or larger, it is not possible to distinguish between different materials but the same size. Therefore, this filter cannot be used to separate and remove different materials unless there is a clear difference in the particle size of each material. For example, it may be desirable to remove salt from the fluid and leave certain other minerals in the fluid. Alternatively, it may be desirable to remove only the virus and leave the bacteria. Bacteria are larger than viruses, so a filter based solely on size cannot achieve this goal.
US Pat.No. 5,470,470 (US-A-5470470) U.S. Pat.No. 4,617,120 (US-A-4617120) European Patent No. 0280052 (EP-A-0280052)

  In accordance with a first aspect of the present invention, a filter for fluid is provided, which includes a filter housing having an inflow end and an outflow end, and extending in the lengthwise direction of the housing. A plurality of fibers fixed at the section, wherein the fibers are loaded to selectively block or allow passage of particles having a known charge present in the fluid flowing to the discharge end. Is done.

  According to a second aspect of the present invention, there is provided a method for operating a fluid filter, wherein the filter comprises a filter housing having a first end and a second end; A plurality of fibers extending in the lengthwise direction of the housing and fixed at a first end, wherein the method comprises particles having a predetermined charge. Selecting the direction of the load applied to the fiber to prevent movement from the end of the second to the second end, applying the load to the fiber, and second from the first end Passing the fluid to be filtered to the end of the.

  It is further desirable to utilize the filter to charge particles in the fluid to capture or control it as it passes through the filter. For example, drinking water in a country is brown even though it is safe to drink. Its appearance makes consumers uncomfortable and it is therefore desirable to be able to change these properties so that the water is clean and attractive to consumers.

  Therefore, a further object of the present invention is to alleviate this problem in a simple but effective manner.

  According to a third aspect of the present invention, there is provided a method of using a filter to alter the precipitation characteristics of particles in a fluid, wherein the filter comprises a first end and a second end. A filter housing and a plurality of fibers extending in the lengthwise direction of the housing and fixed at a first end, wherein the method comprises a predetermined charge on the fibers. ), Wherein the load is selected based on the load of a particle in the fluid, and the fluid whose precipitation characteristics are to be changed from the first end to the first end. Passing through the two ends and allowing the particles to settle in the fluid.

  Preferred features and embodiments are described in the dependent claims.

  While the present invention may be implemented in a variety of ways, the following describes some specific embodiments by way of example with reference to the drawings.

  Referring to FIG. 2a, a filter 200 according to a first embodiment of the present invention is shown. This filter is housed in a cylindrical filter housing 201, the size of which can be selected according to the specific fluid pressure, flow rate or required volume. Alternatively, the housing can be shaped such that its width gradually decreases towards its distal end. For example, in certain applications, the housing has an outer diameter of 315 mm and an inner diameter of 290 mm. The filter housing can be made from a suitable rigid material such as metal or a suitable plastic material. The housing has an inflow end 202 and a discharge end 203 that allow filtration media to enter and exit the filter, respectively.

  The inflow end is covered with an inflow cap 204 having a plurality of inflow openings 205. Each of the openings 205 is fed from a separate inlet pipe 206, which allows various liquids and / or gases to be fed to the filter in parallel if necessary. Appropriate connecting means 207 are provided to connect the inlet pipe to a further piping system (not shown) that supplies liquid and / or gas to the filter at the required pressure and flow rate.

  An internal fixing ring 208 is disposed (inserted) adjacent to the inflow end 202 of the housing 201. This ring provides a lip on which the head base 209 is rigidly mounted. It is preferable (but not essential) that the head substrate 209 can be easily removed to facilitate maintenance and / or replacement. The volume of the filter housing between the inflow cap 204 and the head substrate 209 defines an inflow chamber 210 in which incoming liquids and / or gases can mix.

  The drain end 203 of the housing may remain open, or an outlet cap and outlet pipe may be provided to guide the outgoing fluid after it has passed through the filter.

  Referring now to FIG. 3, the head substrate 209 comprises a removable plate 300, which is a suitable rigid material having a plurality of apertures spaced along the periphery for receiving a bundle of fibers. One of this bundle of fibers is shown at 303, for example from a metal or plastic material. The fibers are fixed in a metal fixing collar 710 as shown in FIG. In use, the collar 710 is placed around the fiber bundle and then crimped as shown in FIG. 7 to secure the fibers together. The ends of the fibers 720 are then fused or dissolved to form a solid mass and become one. Thereafter, the fixing collar can be disposed in the opening 301 of the head base so that a part of the collar contacts the shoulder (not shown) of the opening.

  Alternatively, the fibers can be conveniently disposed in the head substrate, for example, by dissolving about 30 mm of the fiber ends to form a solid mass and then cross struts (not shown) in the openings 301. ) To fix the mass. There are a plurality of small openings (small holes) 302 between and surrounding the fiber bundle openings 301, the purpose of which is to allow fluid to flow in through the head substrate. is there. Both types of openings are preferably spaced at equidistant points along the periphery of the head substrate to provide a generally uniform distribution of fibers and also a generally uniform fluid flow between and through the fiber bundles. It is like that.

  Referring again to FIG. 2a, within the filtration chamber 213 below the head substrate, the individual fibers 211 of the bundle 301 can be spread from corner to corner of the housing 201 to form a fairly uniform fiber curtain. I understand. The fibers extend substantially axially along the length of the filtration chamber 213 and are arranged substantially parallel to the direction of flow through the chamber. In this preferred embodiment, the fibers 211 may be fixed at the discharge end 203 rather than left free. In this way, the current through the fiber can flow from one end of the filter to the other. In this embodiment, the lower fiber end 215 is connected to a discharge substrate head 216 having an opening (not shown) for securing the fiber bundle and an additional hole (also not shown) for the filtrate to exit. It is fixed against. The discharge substrate head 216 is secured in place in any suitable manner, for example, with a further ring located inside the filter housing 201. Instead, the discharge base head 216 can be left in a free state. With this structure, the filter can be backwashed.

  In the alternative embodiment shown in FIG. 2b, the fiber ends are not fixed at all, they simply hang freely. This embodiment can be used when the fluid to be filtered is conductive. This is because in that case the charge can flow through the fibers and into the liquid. But if possible, this embodiment should be avoided. This is because a coating can be formed on the fiber that can adversely affect the flow of current.

  The fibers 211 can be of an appropriate size and made of a conductive material, but are preferably made of metal fibers or carbon fibers. In certain embodiments, the fibers have a diameter of 0.15 mm to 0.5 mm. The fibers may be solid or hollow, and may be circular, rectangular or other cross-sectional shapes. For some applications, it may be advantageous for the fiber to be at least partially elastic along or across the fiber length. For such fibers, the desired shape recovery characteristics can also be selected depending on the desired application. The fibers may have a smooth or rough surface and may be coated if necessary. Fiber coatings such as Teflon and zinc would be appropriate.

  In a further embodiment shown in FIG. 2c, the fiber is magnetized, but no current flows through it. Magnetization along the fiber is achieved by placing magnetic poles 240a, 240b opposite each end of the filter to impart a magnetic charge to the fiber with a predetermined polarity, as shown in FIG. 2c. Alternatively, magnetization across the fiber can be achieved by placing the magnet in or near the filter housing and placing the magnet in the center of the housing with the opposite pole facing radially outward (not shown). .

  When using an embodiment of the filter as shown in FIG. 2a, current is supplied via a wire 230 connected to the upper end of each fiber bundle. The current imparts a predetermined charge to the fiber. Referring to FIG. 6a, the charge passing through the fibers creates an electric field (indicated by reference numeral 650) between the fibers. As the fluid to be filtered passes through the filter, the electric field prevents the passage of the charged particles 660 that flow in the opposite direction to the electric field toward which the charged particles 660 are directed.

  These charged particles therefore gather within the filter to form a filter cake, while the rest of the fluid passes through the filter. When the filter is run for a while, a considerable amount of filter cake is produced. This can be removed by flushing. In order to flush the filter cake from the filter, the direction of the charge on the fiber is reversed as shown in FIG. 6b, so that the charged particles previously blocked from passing through the fiber for recovery. It will be able to flow freely.

  For those skilled in the art, it is clear that the particles in the fluid to be filtered are charged in nature. Some particles are positively charged and other particles are negatively charged.

  When using a magnetically loaded filter as shown in FIG. 2c, selected loaded particles can be blocked in the same way as with the electric field of FIG. 2a. The magnetic field generated between the fibers prevents the movement of the opposite magnetic charge particles that are present in the filter. To flush the filter cake, the poles can be inverted so that the loaded particles can pass through the fibers.

  With regard to an alternative use of the filter of FIG. 2a, FIG. 2b or FIG. 2c, the filter can be used to alter the precipitation characteristics of the fluid in the fluid by changing the particle load. The fiber's magnetic / electric field changes the load of certain particles as the fluid passes through the filter. The particles can then be collected or separated simply by allowing precipitation. One example for the use of this method is to change the precipitation characteristics of drinking water to improve its appearance. In some parts of the world, drinking water is brown even if it is safe enough to drink. Usually, brown particles do not precipitate in the liquid. Brown particles can be removed by passing water through the filter to change its sedimentation characteristics and then allowing the water to settle (sediment), thereby separating the particles from the drinking water. It becomes possible.

  With respect to the alternative embodiment shown in FIGS. 4 a and 4 b, it can be seen that an elongated balloon or inflatable member 212 is attached to the center of the filtration chamber 213 in addition to the fibers. The balloon is centrally located within the chamber and extends substantially axially along the chamber so as to be disposed substantially parallel to the direction of flow through the filter. In the first mode shown in FIG. 4a, the balloon is relaxed, so that there is little or no hindrance to the free flow of fluid through the filter unless the fiber is loaded. The fluid entering through the small holes 302 flows between the fiber bundles and between the individual fibers between the gaps 214 until substantially out of the outlet, without being blocked. In this mode there is no filtration but the van der Waals effect will appear.

  When it is desired to initiate filtration, the balloon 212 is inflated by a control fluid (hydraulic or pneumatic) supplied along the inlet line 216. Alternatively, the balloon can be filled with a material that resists considerable movement (whether rapid or slow movement) such as powder or particles such as sand. As shown, the conduit may pass through the head substrate 209, and the pipe can be bypassed from the side or outlet end (not shown).

  In the filtration mode of FIG. 4b, the inflated balloon forms a pinch (clamping) point 403 consisting of a narrow annular region or annulus between its periphery and the inner periphery of the housing, where the effective flow area is Is the smallest. The location of the pinch point 403 defines an upstream section 406 of the inlet section of this pinch point and a downstream section 407 on the outlet side. Preferably, the shape of the balloon is such that it is substantially symmetrical about the central longitudinal (longitudinal) axis 408 of the chamber when it is in an inflated state. Depending on the application, the upstream section and the downstream section may be mirror images of each other. Alternatively (not shown) the upstream section may form an annular region that changes more rapidly along the length of the filter than the downstream section, and vice versa.

  In any event, when the filter is in the filtration mode, fluid passing through it is contacted with a gradually decreasing annular surface area up to the pinch point 403 and thereafter with a gradually increasing annular surface area. The gradual (gradually changing) surface area characteristic before the pinch point makes the balloon 212 stiff at its ends and soft at its center so that the balloon 212 is generally oval when inflated. It is strengthened by.

  When the balloon is inflated, it begins to apply a radial force to the surrounding fibers, pressing the fibers together and pressing against the rigid wall 201 of the filter housing. This, of course, reduces the size of the channel 409 between the fibers.

  When the fiber 211 is made of a compressible material, the fiber itself also starts to deform, thereby further reducing the size of the channel 409 through which the fluid can pass.

  Once the balloon is inflated to the required size, the charge or magnetic charge is made functional and the fluid to be filtered is passed through the filter. Typically, the fluid will consist of water or other liquid mixed with one or more solid particles of various sizes. As water and particles pass through the upstream section, the particles are trapped between the fibers by an electric or magnetic field combined with a gradually decreasing channel size. Particles with a given load will be trapped by the electric / magnetic field 650. For the remaining particles, the larger particles 410 will be caught relatively early by the graduated filter, whereas the finer particles 411 will be caught in the vicinity of the pinch point 403. Become. Very fine particles 412 will be caught just before the pinch point.

  Larger particles 410 trapped in the coarse filter substrate (which is formed by the upper portion of the upstream section) due to the taper and progressive increase in the pushing force of the fibers in the upstream section. Is prevented from sliding down. Of course, it would not be preferable for the large particles 410 to slide down. This is because large particles that may move down towards the pinch point tend to reduce the taper's grading characteristics and thus the ability of the filter to systematically separate out different sized particles. . In embodiments of the invention, the taper's grading characteristic ensures that each fiber is firmly held by the surrounding fibers. The fibers in the upstream section cannot “float” or move, nor can the captured particles move.

  Typically, the balloon is inflated by an appropriate amount so that only fluid can pass through the pinch point. However, of course, in some applications it is quite acceptable for very fine particles to pass through the filter, and it is clear that in such cases it is not necessary to inflate the balloon to the same extent. By changing the hydraulic or pneumatic pressure in line 216, the filter can be adjusted to allow only particles smaller than the desired size to pass.

  In a further embodiment shown in FIG. 8, the filter comprises two balloons 812a and 812b arranged in series along its central axis. A fiber 811 surrounds the balloon, and when the balloon is inflated as shown in FIG. 8, it presses the fiber tightly against the inner wall of the housing. In this manner, one or more filter stages are obtained, and the two balloons 812a and 812b can be used to filter out two different types of particles based on particle size or other characteristics.

  FIG. 5 schematically illustrates the flushing process for the embodiment of FIGS. 4a and 4b. To rinse the filter, the electric or magnetic field 650 is reversed and the pressure in the balloon 212 is released, thereby removing the pressing force from the fiber and causing them to be compressed as shown at 503. Allowing you to return to a free state. As the size of the flow path 504 increases, the force with which the fibers catch the filter cake decreases and the rinse media 505 allows the cake to be completely swept away. This rinsing medium 505 can be a suitable cleaning liquid or gas, such as water, steam, or a medium to be filtered (containing particulates). The rinsing medium 505 is passed through the filter in the same direction that the medium to be filtered is passed in the filtration mode, i.e. the filter is forward washed.

  In filter embodiments where both the balloon and charge or magnetic charge are present, the balloon is low pressure so as to promote uniform flow between the fibers and not necessarily create a high pressure gap between the fibers as in the previous embodiment. Can only be used with

  It should be understood that such an embodiment would comprise one or more balloons arranged to surround the fibers as in the prior art rather than the central balloon shown in FIGS. 4a and 4b.

  Appropriate valves 506 and tubing 507 can be used so that the cleaning media and filter cake do not contaminate the filtrate. Upstream and / or downstream pressure sensors 508, 509 can be used to determine if the filter has been clogged excessively by the filter cake and if a flushing process needs to be performed. The treatment can be carried out completely automatically, which maximizes the time that the filter can be used in filtration mode and therefore increases the throughput.

  As part of the flushing process, the filter or fiber can be sonicated to help shake and loosen the cake. Furthermore, it may be desirable to dry the filter cake prior to discharge by means of generating a vacuum in the filter or flowing hot air therethrough.

  Of course, the flushing process described above with reference to FIG. 5 is always performed in the forward direction, but in the alternative embodiment of FIG. 2a (in which the fibers are anchored at both ends) instead or in addition Backwashing is available (in each case the balloon pressure may or may not be released).

  The filter of the present invention can be freely resized as desired depending on the amount to be filtered and / or the application. In one preferred form, the filter can be manufactured as a plug-in module in a variety of different sizes.

  Although the filter is illustrated with its longitudinal axis vertical, it will be apparent that in certain applications the axis may be placed horizontally. The fluid passing through the filter can be pumped at high or low pressure, or alternatively, it can pass through the filter solely by the action of gravity.

  One skilled in the art will appreciate that a variety of different parameters can be freely adjusted as required according to the particular application. Such adjustable parameters include pressure, temperature, fiber size, fiber length, fiber coating, load on the fiber, the magnetic field strength of the area within the housing and the fiber and fluid, the manner in which the fiber is anchored, the flow volume (flow volume), These include the material of the filter housing, the type of feed, the method of inflating the balloon, the taper of the balloon, the amount and pressure of the flushing material, and the addition of gas to the mixture.

There are many specific applications that would benefit from the use of the filter according to the present invention. Typical uses include the following.
1. Filtration for reverse osmosis 2. Removal of cement, sand, etc. following industrial processes such as precast concrete. 3. Separation of coagulated product 4. Separation of biological tissue Separation of coagulated blood, etc. 6. Separation of wastewater from plant components such as olive oil products. Rough reduction in turbidity of water required for technical or legal reasons 8. 8. Removal of silt from liquid / water Ballast water

It is a longitudinal section through a conventional filter. FIG. 2 is a longitudinal section through the filter of FIG. 1 in filtration mode. It is longitudinal direction sectional drawing which passes along 1st Embodiment of this invention. It is longitudinal direction sectional drawing which passes along 2nd Embodiment of this invention. It is longitudinal direction sectional drawing which passes along 3rd Embodiment of this invention. It is a detailed top view of the head substrate of each embodiment. It is longitudinal direction sectional drawing which passes along 4th Embodiment of this invention. It is longitudinal direction sectional drawing which passes along 4th Embodiment of this invention. FIG. 5 is a longitudinal cross-sectional view through the filter of FIG. 4 in filtration mode. FIG. 3 is a schematic explanatory diagram relating to blocking and passing performance of the filter of FIGS. 2a and 2b. FIG. 3 is a schematic explanatory diagram relating to blocking and passing performance of the filter of FIGS. 2a and 2b. It is a schematic explanatory drawing of the fiber fixing system by this invention. It is longitudinal direction sectional drawing which passes along 5th Embodiment of this invention.

Explanation of symbols

200 Filter 201 Filter housing 202 Inflow end 203 Outlet end 204 Inflow cap 205 Inflow opening 206 Inflow pipe 207 Connection means 208 Internal fixing ring 209 Head base 210 Inflow chamber 211 Fiber 212 Balloon (inflatable member)
213 Filtration chamber 214 Gap 215 Lower fiber end 216 Discharge substrate head 230 Wire 240a, 240b Magnetic pole 300 Plate 301 Opening 302 Small opening 303 Fiber bundle 403 Pinch point 406 Upstream section 407 Downstream section 409 Flow path 410 412 Particle 504 Flow path 505 Rinse medium 506 Valve 507 Piping 508,509 Pressure sensor 660 Charged particle 710 Fixing color 720 Fiber 811 Fiber 812a, 812b Balloon

Claims (31)

A fluid filter,
A filter housing (201) having an inflow end (202) and a discharge end (204);
A plurality of fibers (211) extending in the length direction of the housing and fixed at the inflow end,
A filter wherein the fibers are loaded to selectively block or allow passage of particles having a known load present in the fluid flowing to the discharge end.   The filter according to claim 1, wherein the load is electrical.   The filter according to claim 1, wherein the load is magnetic.   The filter according to any one of claims 1 to 3, wherein the direction of the load is reversible.   The filter according to claim 2 or 4, wherein the load is generated along the fibers (211).   The filter according to claim 3 or 4, characterized in that the load is generated across the fibers (211).   The filter according to any one of claims 1 to 6, wherein the fibers (211) are made of either metal fibers or carbon fibers.   The inflatable member (212) further comprises an inflatable member that, when inflated, presses the fiber against the filter housing (201) and the first end (202). 8. A gradual filter base is formed between the expandable member and a pinch region (403) between the inflatable member and the inner surface of the housing. The filter according to claim 1.   9. A filter according to claim 8, comprising at least two inflatable members (212, 812) arranged in series along the longitudinal axis of the filter. A method of operating a filter for fluid, the filter comprising a filter housing (201) having a first end (202) and a second end (204), and a length direction of the housing A plurality of fibers (211) extending at the first end and fixed at the first end,
The method
Selecting the orientation of the load applied to the fibers such that particles having a predetermined load are prevented from moving from the first end to the second end;
Applying the load to the fibers;
Passing a fluid to be filtered from the first end to the second end.   The method of claim 10, wherein the load applied to the fiber (211) is electrical.   The method of claim 10, wherein the load applied to the fiber (211) is magnetic.   13. The method according to claim 12, wherein the magnetic charge is applied across the fiber (211).   12. The method according to claim 11, wherein the charge is applied by an electric current along the fiber (211).   15. The method of any one of claims 10 to 14, further comprising the step of subsequently reversing the direction of the load on the fibers (211) to allow the clogged particles to be swept away from the filter. The method according to claim 1. The filter further comprises an inflatable member (212) extending along the longitudinal axis of the filter housing;
The method involves the expansion to create a uniform flow of the fibers through the filter prior to passing the fluid to be filtered from the first end (202) to the second end. 16. A method according to any one of claims 10 to 15, further comprising inflating the enabling member.   Prior to passing the fluid to be filtered from the first end to the second end, the inflatable member is further expanded to press the fibers against the housing, and the first 17. A method according to claim 16, characterized in that a graded filter substrate is formed between the end (202) of the tube and a pinch region (403) between the inflatable member and the inner surface of the housing.   18. A method according to claim 17, wherein at least two inflatable members are arranged in series along the longitudinal axis of the filter. The filter further comprises at least one inflatable member (212) arranged to surround the fibers, the inflatable members adapted to press the fibers together when inflated;
The method further expands the expandable member to compress the fibers prior to passing the fluid to be filtered from the first end to the second end, and the first 17. A gradual filter substrate is formed between the end (202) of the tube and a pinch region (403) between the inflatable member and the fiber. Method.   20. The method of claim 19, wherein at least two inflatable members are placed in series along the longitudinal axis of the filter.   The method according to any one of claims 9 to 18, wherein the fibers are further fixed at the discharge end.   21. A method as claimed in any one of claims 9 to 20 wherein the fluid to be filtered is loaded.   22. A method according to any one of claims 15 to 21 comprising washing the filter by releasing the inflated state of the inflatable member. A method of changing the sedimentation characteristics of particles in a fluid using a filter, the filter comprising a filter housing (201) comprising a first end (202) and a second end (204); A plurality of fibers (211) extending in the length direction of the housing and fixed at the first end,
The method
Applying a predetermined load to the fibers, wherein the load is selected based on a load of a particle in a fluid;
Passing a fluid whose precipitation characteristics are to be changed from the first end to the second end;
Allowing the particles to settle in a fluid.   The method of claim 24, further comprising the step of separating the precipitated particles from the fluid.   26. A method according to claim 24 or claim 25, wherein the particles are loaded as they pass through the filter.   27. A method according to any one of claims 24 to 26, wherein a load on the fibers prevents certain particles in the fluid from passing through the filter.   28. A method according to any one of claims 24 to 27, wherein the load is applied by an electric current.   28. A method according to any one of claims 24 to 27, wherein the load is applied by a magnetic field.   30. A method according to any one of claims 24 to 29, wherein the fluid is drinking water.   31. A method according to any one of claims 24 to 30, wherein the filter is as claimed in any one of claims 1 to 9.

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