Filtration Equipment

Abstract

This filtration device includes a housing, a first filter chamber, a filtration unit, a rotary member, and a drive device. The first filter chamber is an internal space of the housing. The filtration unit is attached to the housing in such a manner as to be in contact with the first filter chamber. The rotary member is supported by the housing so as to be rotatable with respect to the housing. The drive device rotates the rotary member. The filtration unit includes a first electrode, second electrode, filter medium, and second filter chamber. The first electrode has a plurality of first openings. The second electrode has a plurality of second openings and is provided to face one surface of the first electrode. The filter medium is provided between the first electrode and second electrode and has a plurality of mesh openings. The second filter chamber is provided in contact with the surface of the second electrode on the side opposite to the filter medium. The rotary member includes a third electrode facing the first electrode with the first filter chamber interposed therebetween.

Description

[Technical field]

[0001] The present disclosure relates to a filtration device. [Background technology]

[0002] In solid-liquid separation by filtration of particle-fluid-system slurry, methods are known that use electroosmosis or electrophoresis to separate the particles to be separated from the liquid (see, for example, Patent Documents 1 and 2). Solid-liquid separation using electroosmosis is a method in which a voltage and pressure are applied to a cake layer sandwiched between electrodes, and the water in the cake layer is expelled through the filter medium by the electroosmotic action. Solid-liquid separation using electrophoresis is a method in which the particles in the slurry are moved by electrophoresis and brought into direct contact with the filter medium, thereby separating the particles in the slurry. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 61-018410 [Patent Document 2] International Publication No. 2004 / 045748 Summary of the Invention [Problem to be solved by the invention]

[0004] In a method for performing solid-liquid separation by directly contacting particles in a slurry with a filter medium, there is a possibility that the filtration rate will decrease due to clogging of the filter medium.

[0005] An object of the present disclosure is to provide a filtration device capable of improving the filtration speed. [Means for solving the problem]

[0006] A filtration device according to one aspect of the present disclosure includes a housing, a first filtration chamber which is an internal space of the housing, a filtration unit attached to the housing so as to be in contact with the first filtration chamber, a rotating member supported by the housing so as to be rotatable relative to the housing, and a drive device which rotates the rotating member, wherein the filtration unit includes a first electrode having a plurality of first openings, a second electrode having a plurality of second openings and disposed opposite one side of the first electrode, a filter material having a plurality of meshes and disposed between the first electrode and the second electrode, and a second filtration chamber disposed in contact with the side of the second electrode opposite the filter material, and the rotating member includes a third electrode which faces the first electrode across the first filtration chamber.

[0007] A filtration device according to another aspect of the present disclosure includes a housing, a first filtration chamber which is an internal space of the housing, a plurality of filtration units attached to the housing so as to be in contact with the first filtration chamber, a rotating member supported by the housing so as to be rotatable relative to the housing, and a drive unit which rotates the rotating member, wherein the filtration units include a first electrode having a plurality of first openings, a second electrode having a plurality of second openings and disposed opposite one side of the first electrode, a filter material having a plurality of meshes and disposed between the first electrode and the second electrode, and a second filtration chamber disposed in contact with the surface of the second electrode opposite the filter material, the rotating member includes a third electrode which faces the first electrode across the first filtration chamber, and the plurality of filtration units are arranged side by side in a direction along the rotation axis of the rotating member. Effect of the Invention

[0008] According to the filtration device of the present disclosure, it is possible to improve the filtration speed. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view of the filtering device according to the first embodiment. [Diagram 2] FIG. 2 is an enlarged view of part A in FIG. [Diagram 3] FIG. 3 is an enlarged view of part B in FIG. [Figure 4] FIG. 4 is an enlarged view of part C in FIG. [Diagram 5] FIG. 5 is a perspective view of a rotating member and a filtration unit according to the first embodiment. [Figure 6] FIG. 6 is an exploded perspective view of the rotating member and the filtration unit according to the first embodiment. [Figure 7] FIG. 7 is an exploded perspective view of the rotating member and the filtration unit according to the first embodiment. [Figure 8] FIG. 8 is an exploded perspective view of the rotating member and the filtration unit according to the first embodiment. [Figure 9] FIG. 9 is a schematic diagram of the filtering device according to the first embodiment. [Figure 10] FIG. 10 is a cross-sectional view that illustrates a schematic configuration of the first electrode, the filter medium, and the second electrode. [Figure 11] FIG. 11 is an equivalent circuit diagram showing the filtering device according to the first embodiment. [Figure 12] FIG. 12 is an equivalent circuit diagram showing a filtration unit according to a first modification of the first embodiment. [Figure 13] FIG. 13 is a cross-sectional view of the filtering device according to the second embodiment. [Figure 14] FIG. 14 is a front view of the filtering device according to the second embodiment. [Figure 15] FIG. 15 is a cross-sectional view of the filtering device according to the embodiment in a state in which the rotation axis is parallel to the vertical direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the following modes for carrying out the invention (hereinafter, referred to as embodiments). Furthermore, the components in the following embodiments include those that a person skilled in the art can easily imagine, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the components disclosed in the following embodiments can be appropriately combined.

[0011] (Embodiment 1) FIG. 1 is a cross-sectional view of a filtration device according to the first embodiment. The filtration device 10 according to the first embodiment is a device for separating particles from a slurry (raw liquid) in which particles are dispersed in a liquid. Specifically, the filtration device 10 can be applied to the life science field, sewage treatment, wastewater treatment, and the like. In the life science field, the filtration device 10 can be applied to the bioindustry for culturing microbial bodies such as cultured cells, microalgae, bacteria, and viruses, the biopharmaceutical drug discovery and cosmetics industry, which are fields of application and utilization of enzymes, proteins, polysaccharides, lipids, and the like produced extracorporeally and intracorporeally by cultured microbial bodies, and the beverage industry for handling brewing, fermentation, juicing, beverages, and the like. In the sewage treatment and wastewater treatment fields, the filtration device 10 can be applied to the separation of biomass particles from a fine biomass aqueous slurry that is difficult to filter. Alternatively, the filtration device 10 can be applied to the concentration and recovery of colloidal particles from a colloidal particle-based slurry in which surface-charged particles are highly dispersed by an electric repulsive action.

[0012] As shown in FIG. 1, the filtration device 10 according to the first embodiment includes a housing 80, a first filtration chamber 30, a supply unit 81, a discharge unit 83, a rotating member 40, a drive device 13, and a filtration unit 100.

[0013] As shown in FIG. 1, the housing 80 is a member that supports the rotating member 40 and the filtering unit 100. The housing 80 has a space inside. The housing 80 can accommodate the rotating member 40 and the filtering unit 100 inside. The housing 80 is fixed to a base 200 placed on an installation surface 300. As shown in FIG. 2, the housing 80 includes a third connecting conductor 853 and a brush 854. The third connecting conductor 853 is conductive. The third connecting conductor 853 is attached to one end of the housing 80. The brush 854 is conductive and connected to the third connecting conductor 853. As shown in FIG. 3, the first filtering chamber 30 is the internal space of the housing 80.

[0014] As shown in FIG. 1, the supply unit 81 is attached to the housing 80. A gap between the supply unit 81 and the housing 80 is sealed by a sealing member. The supply unit 81 supplies a slurry (undiluted liquid) to the first filtration chamber 30. As shown in FIG. 3, the supply unit 81 includes a supply port 811 which is an opening provided on the outer circumferential surface. A pipe is connected to the supply port 811. The slurry (undiluted liquid) pressurized by a pressurizing device or the like is supplied to the first filtration chamber 30 via the pipe and the supply port 811.

[0015] As shown in FIG. 1, the discharge unit 83 is attached to the housing 80. A gap between the discharge unit 83 and the housing 80 is sealed by a seal member. The discharge unit 83 discharges the concentrated slurry (undiluted liquid) in the first filtration chamber 30 to the outside. As shown in FIG. 3, the discharge unit 83 has a concentrated liquid discharge port 831 which is an opening provided on the outer circumferential surface. A pipe is connected to the concentrated liquid discharge port 831. Due to the pressure difference between the inside and the outside of the first filtration chamber 30, the concentrated slurry (undiluted liquid) in the first filtration chamber 30 is discharged to the outside through the concentrated liquid discharge port 831 and the pipe. Note that a pressure reducing device such as a vacuum pump may be provided in the pipe connected to the concentrated liquid discharge port 831.

[0016] The rotating member 40 is disposed inside the housing 80. The rotating member 40 is supported by the housing 80. The rotating member 40 can rotate relative to the housing 80. The rotating member 40 rotates about a rotation axis R. The rotation axis R is parallel to the horizontal direction. In Figures 1 to 4, the left-right direction on the paper surface is the horizontal direction. In the following description, the direction parallel to the rotation axis R is referred to as the axial direction. The direction parallel to a straight line perpendicular to the rotation axis R is referred to as the radial direction. The direction along the circumference centered on the rotation axis R is simply referred to as the circumferential direction.

[0017] As shown in Figs. 2 and 3, the rotating member 40 includes a shaft 41, two flanges 43, and a third electrode 33. The shaft 41 is a rod-shaped member. The shaft 41 is connected to the driving device 13. A gap between the shaft 41 and the housing 80 is sealed by a seal member. As shown in Figs. 2 and 3, the shaft 41 includes an internal conductor 412 having electrical conductivity. As shown in Fig. 2, one end of the internal conductor 412 contacts the brush 854. Therefore, the internal conductor 412 is electrically connected to the third connecting conductor 853.

[0018] As shown in FIG. 3, the flange 43 is provided on the outer circumferential surface of the shaft 41. The flange 43 contacts the first filtration chamber 30. The two flanges 43 are arranged on both sides of the filtration unit 100. The flanges 43 are formed in a substantially disk shape. The two flanges 43 include a first flange 43a and a second flange 43b. The first flange 43a and the second flange 43b have the same structure and are arranged at different positions in the axial direction. The first flange 43a is arranged on the supply unit 81 side with respect to the filtration unit 100. The first flange 43a overlaps with the supply unit 81 when viewed from the radial direction. The second flange 43b is arranged on the discharge unit 83 side with respect to the filtration unit 100. The second flange 43b overlaps with the discharge unit 83 when viewed from the radial direction.

[0019] As shown in FIG. 4, the flange 43 includes a mounting portion 431, an agitating portion 433, and an internal conductor 437. The mounting portion 431 is a portion that supports the third electrode 33. The third electrode 33 is attached to a surface of the mounting portion 431 facing the axial direction. The third electrode 33 is a plate-shaped member and faces the first filter chamber 30. The mounting portion 431 is provided at the radially outer end of the flange 43. The agitating portion 433 is provided on the radially inner side (shaft 41 side) of the mounting portion 431. As shown in FIG. 7 and FIG. 8, the agitating portion 433 includes a plurality of grooves 434. The groove 434 is provided from the shaft 41 to the mounting portion 431. The groove 434 forms an arc when viewed from the axial direction. The plurality of grooves 434 includes a plurality of first grooves 435 and a plurality of second grooves 436.

[0020] The first groove 435 is disposed on one of two surfaces of the stirring portion 433 facing the axial direction. The first grooves 435 are disposed at equal intervals along the circumferential direction. As shown in FIG. 7, the first grooves 435, when viewed from the axial direction, describe a circular arc that is convex toward the opposite direction to the rotation direction DR of the rotating member 40. Therefore, when the rotating member 40 rotates, the slurry (raw liquid) in contact with the first groove 435 is guided radially inward (toward the shaft 41).

[0021] The second groove 436 is disposed on the other of the two surfaces of the stirring portion 433 facing the axial direction. That is, the second groove 436 is disposed on the rear side of the first groove 435. The second grooves 436 are disposed at equal intervals along the circumferential direction. As shown in FIG. 8, the first groove 435 describes a circular arc that is convex toward the rotation direction DR of the rotating member 40 when viewed from the axial direction. Therefore, when the rotating member 40 rotates, the slurry (raw liquid) in contact with the second groove 436 is guided to the outside in the radial direction (the side opposite to the shaft 41 side).

[0022] In the first flange 43a, the first groove 435 faces the filtration unit 100. Therefore, the slurry (undiluted liquid) between the first flange 43a and the filtration unit 100 is guided radially inward. In the second flange 43b, the second groove 436 faces the filtration unit 100. Therefore, the slurry (undiluted liquid) between the second flange 43b and the filtration unit 100 is guided radially outward.

[0023] 3, the inner conductor 437 is connected to the inner conductor 412 of the shaft 41. The inner conductor 437 is also connected to the third electrode 33. Therefore, the third electrode 33 is electrically connected to the third connecting conductor 853.

[0024] The driving device 13 is a device that rotates the rotating member 40. The driving device 13 includes an electric motor and a reduction gear. The electric motor is connected to the shaft 41 of the rotating member 40 via the reduction gear. The torque generated by the electric motor is increased by the reduction gear and then transmitted to the shaft 41.

[0025] As shown in FIG. 3, the filtration unit 100 is attached to the housing 80. The filtration unit 100 is disposed between the supply unit 81 and the discharge unit 83. A part of the filtration unit 100 is disposed at a position between the two flanges 43 of the first filtration chamber 30. As shown in FIGS. 3 and 4, the filtration unit 100 has a case 110, a first electrode 31, a second electrode 32, a filter medium 34, a second filtration chamber 35, a filtrate discharge port 105, a first connecting conductor 101, and a second connecting conductor 102. The case 110 is a member that holds the first electrode 31, the second electrode 32, and the filter medium 34. The case 110 is formed of a conductive material.

[0026] 4, the first electrode 31, the second electrode 32, and the filter material 34 are attached to a case 110. The first electrode 31, the second electrode 32, and the filter material 34 are annular. In the filtration unit 100, the first electrode 31, the second electrode 32, and the filter material 34 are provided on both sides of a second filter chamber 35. That is, the filtration unit 100 includes two first electrodes 31, two second electrodes 32, two filter materials 34, and one second filter chamber 35.

[0027] FIG. 9 is a schematic diagram of the filtration device according to the first embodiment. As shown in FIG. 9, the first electrode 31 and the second electrode 32 are mesh-shaped electrodes. Specifically, the first electrode 31 has a plurality of conductive fine wires 31a, and a plurality of first openings 31b are provided between the plurality of conductive fine wires 31a. The second electrode 32 has a plurality of conductive fine wires 32a, and a plurality of second openings 32b are provided between the plurality of conductive fine wires 32a. The second electrode 32 is provided facing one surface of the first electrode 31 via the filter material 34. In other words, the filter material 34 is provided between the first electrode 31 and the second electrode 32. The first electrode 31 and the second electrode 32 are provided in direct contact with the filter material 34. The first electrode 31 faces the third electrode 33 across the first filter chamber 30. The second electrode 32 faces the second filter chamber 35. The conductive fine wires 31a and the conductive fine wires 32a may be made of metal or carbon fiber. The first electrode 31 and the second electrode 32 are not limited to being in direct contact with the filter medium 34, and may be arranged with a gap between them.

[0028] The filter medium 34 includes a filtration membrane 34a and mesh openings 34b. The filtration membrane 34a has a plurality of mesh openings 34b. An electric field acts on the filtration membrane 34a. For example, a microfiltration membrane (MF membrane (Microfiltration Membrane)) is used as the filter medium 34. In the first embodiment, the filter medium 34 is formed of an insulating material such as a resin material, and the first electrode 31 and the second electrode 32 are insulated by the filter medium 34. Note that in FIG. 9, the first opening 31b of the first electrode 31, the second opening 32b of the second electrode 32, and the mesh openings 34b of the filter medium 34 are shown to have the same size, but this is merely a schematic illustration for the purpose of explanation, and the sizes of the first opening 31b, the second opening 32b, and the mesh openings 34b may be different.

[0029] FIG. 10 is a cross-sectional view showing the configuration of the first electrode, the filter medium, and the second electrode. As shown in FIG. 10, the diameter D3 of the openings 34b provided in the filter medium 34 is smaller than the diameter D1 of the first opening 31b of the first electrode 31, and smaller than the diameter D2 of the second opening 32b of the second electrode 32. In other words, the arrangement pitch of the multiple conductive fine wires 31a, the arrangement pitch of the multiple conductive fine wires 32a, and the arrangement pitch of the filtration membrane 34a are different from each other. For example, the diameter D1 of the first opening 31b of the first electrode 31 is 0.5 μm or more and 500 μm or less, for example, about 70 μm. The diameter D2 of the second opening 32b of the second electrode 32 is 0.5 μm or more and 1000 μm or less, for example, about 100 μm. The diameter D3 of the plurality of openings 34b provided in the filter medium 34 is about 0.1 μm or more and 100 μm or less, and more preferably about 1 μm or more and 7 μm or less.

[0030] Moreover, the diameter D1 of the first opening 31b of the first electrode 31 is smaller than the diameter D2 of the second opening 32b of the second electrode 32. However, without being limited thereto, the diameter D1 of the first opening 31b of the first electrode 31 may be formed to be the same size as the diameter D2 of the second opening 32b of the second electrode 32. With this configuration, the openings 34b of the filter medium 34 are provided so as not to overlap with the multiple conductive fine wires 31a and the multiple conductive fine wires 32a at least in the region overlapping with the first opening 31b and the second opening 32b. Moreover, the distance between the first electrode 31 and the second electrode 32 is determined by the thickness of the filter medium 34.

[0031] The second filter chamber 35 is an internal space of the case 110. The second filter chamber 35 is disposed between the two second electrodes 32. The second filter chamber 35 is connected to a filtrate discharge port 105. The filtrate discharge port 105 is an opening provided on the outer peripheral surface of the case 110. A pipe is connected to the filtrate discharge port 105. The filtrate 75 in the second filter chamber 35 is discharged to the outside of the filtration unit 100 via the filtrate discharge port 105 and the pipe.

[0032] As shown in Fig. 3, the first connecting conductor 101 is attached to the outer peripheral surface of the case 110. The first connecting conductor 101 is conductive. The first electrode 31 is electrically connected to the first connecting conductor 101 via the case 110. The second connecting conductor 102 is attached to the case 110 via an insulating material. A portion of the second connecting conductor 102 is inserted inside the case 110. The second connecting conductor 102 is connected to the second electrode 32 from the second filter chamber 35 side.

[0033] As shown in FIG. 9, the filtration device 10 includes a first power source 51, a second power source 52, and a third power source 53. The first electrode 31 is electrically connected to the second terminal 51b of the first power source 51 through the first connecting conductor 101 (see FIG. 3). The first electrode 31 is electrically connected to the first terminal 52a of the second power source 52 through the first connecting conductor 101 (see FIG. 3). The second electrode 32 is electrically connected to the second terminal 52b of the second power source 52 through the second connecting conductor 102 (see FIG. 3). The third electrode 33 is electrically connected to the first terminal 53a of the third power source 53 through the third connecting conductor 853 (see FIG. 2). The second terminal 53b of the third power source 53 and the first terminal 51a of the first power source 51 are connected to a reference potential GND. The reference potential GND is, for example, a ground potential. However, the present invention is not limited to this, and the reference potential GND may be a predetermined fixed potential.

[0034] As shown in FIG. 9, the first power supply 51 supplies the first electrode 31 with a first potential V1 having the same polarity as that of the particles 71. The first potential V1 is, for example, −30V. The second power supply 52 supplies the second electrode 32 with a second potential V2 having the same polarity as that of the particles 71 and an absolute value greater than that of the first potential V1. The second potential V2 is, for example, −40V. The third power supply 53 supplies the third electrode 33 with a third potential V3 having a polarity different from that of the particles 71. The third potential V3 is, for example, +30V. The first potential V1, the second potential V2, and the third potential can be set in the range of 1 mV to 1000 V in absolute value.

[0035] Fig. 11 is an equivalent circuit diagram showing the filtration device according to the first embodiment. As shown in Fig. 11, the first power source 51 and the third power source 53 are constant voltage sources, and the second power source 52 is a constant current source. A resistance component R1 and a capacitance component C are connected in parallel between the first electrode 31 and the second electrode 32. The resistance component R1 and the capacitance component C are components equivalently represented by the filter medium 34 having a large number of openings 34b. In addition, a resistance component R2 is connected between the first electrode 31 and the third electrode 33. The resistance component R2 is a resistance component equivalently represented by the slurry (raw liquid) 70 in the first filter chamber 30.

[0036] The second power source 52 may be a constant voltage power source or a constant current power source. In this embodiment, the second power source 52 is a constant current source, so the second potential V2 changes according to the filtering state of the filtering device 10, that is, according to fluctuations in the resistance component R1 of the filtering medium 34 and the resistance component R2 of the first filtering chamber 30. However, the second potential V2 has the same polarity as that of the particles 71, and maintains a value greater than the absolute value of the first potential V1.

[0037] In the first filtration chamber 30, a repulsive force acts on the particles 71 of the slurry (undiluted solution) 70 by driving each electrode, so a concentration gradient occurs in the dispersion state of the particles 71. The slurry (undiluted solution) 70 from which the particles 71 have been separated flows into the second filtration chamber 35 through the first electrode 31, the second electrode 32, and the filter material 34. The filtrate 75 in the second filtration chamber 35 is discharged to the outside of the second filtration chamber 35 through the filtrate discharge port 105.

[0038] The particles 71 are, for example, biomass particles or colloidal particles, and the particle surfaces are negatively charged. Specifically, the particles 71 are chlorella, microalgae spirulina, colloidal silica, Escherichia coli, sewage activated sludge, etc. The diameter of the particles 71 varies depending on the technical field to which it is applied and the type of object to be separated, but is 5 nm or more and 2000 μm or less, for example, about 20 nm or more and 500 μm or less.

[0039] The liquid 72 in which the particles 71 are dispersed is water, and the water molecules 73 are positively charged. This causes the slurry (undiluted liquid) 70 to be in an electrically balanced state as a whole. The liquid 72 is not limited to water, and may be alcohol or the like. In other words, the liquid 72 may be any polar solvent.

[0040] The slurry (undiluted solution) 70 further contains a chromoprotein 74. The chromoprotein 74 is charged with the same polarity (negative) as the particles 71, and has a smaller particle size than the particles 71. The chromoprotein 74 is 10 nm or more and 300 nm or less, for example, about 30 nm. The chromoprotein 74 may be omitted.

[0041] When the slurry (raw liquid) 70 is supplied to the first filtration chamber 30, a repulsive force is generated between the negatively charged particles 71 and the first electrode 31. Also, an attractive force is generated between the negatively charged particles 71 and the third electrode 33.

[0042] Specifically, a stronger repulsive force is generated on the particles 71 located closer to the first electrode 31, and a stronger attractive force is generated on the particles 71 located closer to the third electrode 33. The repulsive and attractive forces generated on the particles 71 act in the direction indicated by the arrow F1, that is, in the direction away from the first electrode 31 and toward the third electrode 33. The negatively charged particles 71 move toward the third electrode 33 by electrophoresis.

[0043] This allows the filtration device 10 to suppress the particles 71 from accumulating on the surface of the first electrode 31 and the surface of the filter medium 34 to form a cake layer. In other words, the filtration resistance of the openings 34b of the filter medium 34 can be suppressed from increasing.

[0044] Furthermore, an attractive force is generated between the positively charged water molecules 73 and the first electrode 31. The attractive force acting on the positively charged water molecules 73 acts in the direction indicated by the arrow F2, that is, in the direction from the third electrode 33 to the first electrode 31. The positively charged water molecules 73 move toward the first electrode 31. At this time, due to the potential difference between the first electrode 31 and the second electrode 32, an electric field is formed from the first electrode 31 to the second electrode 32 so as to penetrate the filter medium 34 in the thickness direction.

[0045] The water molecules 73 that have moved to the first electrode 31 side are pulled to the second electrode 32 side by the force of the electric field and pass through the filter medium 34. As the positively charged water molecules 73 move, the water molecules are pulled to the second electrode 32 side, forming an electroosmotic flow. As a result, the liquid 72 containing the positively charged water molecules 73 flows into the second filter chamber 35. As described above, the particles 71 are separated from the first electrode 31 by electrophoresis and move to the third electrode 33 side, and the filtrate 75 from which the particles 71 have been separated is discharged, thereby increasing the concentration of the particles 71 in the slurry (raw liquid) 70 in the first filter chamber 30.

[0046] In this way, the filtration device 10 can separate the particles 71 by combining electrophoresis, which moves the particles 71 between the first electrode 31 and the third electrode 33 by a repulsive force F (a repulsive force generated between the particles 71 and the first electrode 31), and electroosmosis, which moves the water molecules 73 by an electric field between the first electrode 31 and the second electrode 32 and passes through the filter medium 34. This makes it possible to suppress the formation of a cake layer on the surface of the first electrode 31 and the surface of the filter medium 34, and to improve the filtration speed by several times to ten times or more, compared to a method in which pressure is simply applied to the slurry (raw liquid) 70 to separate the particles 71 having a particle size larger than the mesh openings 34b of the filter medium 34.

[0047] In other words, the concentration of the particles 71 in the slurry (undiluted liquid) 70 in the first filtration chamber 30 can be increased compared to a method in which pressure is simply applied to the slurry (undiluted liquid) 70. In addition, the frequency of cleaning and replacing the filter medium 34 can be reduced, and the slurry (undiluted liquid) 70 can be filtered efficiently. Alternatively, compared to a method in which pressure is simply applied to the slurry (undiluted liquid) 70 to perform filtration, a filtration speed comparable to that of the conventional method can be achieved even if the volume of the first filtration chamber 30 and the area of ​​the filter medium 34 are reduced. In other words, the filtration device 10 can be made smaller.

[0048] In addition, by controlling the electric field formed between the first electrode 31 and the second electrode 32, it is possible to control the particle level (particle diameter) passing through the filter medium 34. For example, by applying a first potential V1=-30V to the first electrode 31 and a second potential V2=-40V to the second electrode 32, a shielding electric field is formed between the first electrode 31 and the second electrode 32, and it is possible to prevent the chromoprotein 74 having a particle diameter smaller than the mesh openings 34b of the filter medium 34 from passing through the filter medium 34.

[0049] That is, even when a filter medium 34 equivalent to a microfiltration membrane (MF membrane) is used, the particle size of the separation target can be changed to that of an ultrafiltration membrane (UF membrane) or a nanofiltration membrane (NF membrane) by controlling the electric field between each electrode of the first power source 51, the second power source 52, and the third power source 53. The ultrafiltration membrane (UF membrane) is a filtration membrane with an opening diameter of about 10 nm or more and 100 nm or less. The nanofiltration membrane (NF membrane) is a filtration membrane with an opening diameter of about 1 nm or more and 10 nm or less.

[0050] The above-mentioned configuration of the filtration device 10 is merely an example, and can be modified as appropriate. For example, the negative electrode filter plate formed by stacking the first electrode 31, the filter medium 34, and the second electrode 32, and the third electrode 33 are arranged in a parallel plate shape facing each other. Without being limited thereto, the negative electrode filter plate formed by stacking the first electrode 31, the filter medium 34, and the second electrode 32, and the third electrode 33 may each be formed to have a curved surface. The shape and arrangement of the negative electrode filter plate and the third electrode 33 can be modified as appropriate according to the shape and structure of the filtration device 10. In addition, the concentration of the slurry (raw solution) 70 supplied to the first filtration chamber 30 is not particularly limited, and can be modified according to the field to which the filtration device 10 is applied.

[0051] In the first embodiment, the internal pressure of the first filter chamber 30 is pressurized and is higher than the internal pressure of the second filter chamber 35. In another aspect, the internal pressure of the second filter chamber 35 may be reduced by evacuation or the like, so that the internal pressure of the first filter chamber 30 is relatively higher than the internal pressure of the second filter chamber 35.

[0052] Moreover, it is preferable that the first potential V1, the second potential V2, and the third potential V3 are appropriately changed according to the type of particles 71 to be separated and the required filtering characteristics.

[0053] The filtration device 10 does not need to include the third power supply 53. Fig. 12 is an equivalent circuit diagram showing a filtration unit according to a first modification of the first embodiment. As shown in Fig. 12, in the first modification of the first embodiment, the third electrode 33 is connected to, for example, a reference potential GND. When the third electrode 33 is connected to the reference potential GND, the filtration device 10 can be made smaller than when a power supply is provided for each of the first electrode 31, the second electrode 32, and the third electrode 33.

[0054] As described above, the filtration device 10 of the first embodiment includes the housing 80, the first filtration chamber 30, the filtration unit 100, the rotating member 40, and the drive device 13. The first filtration chamber 30 is an internal space of the housing 80. The filtration unit 100 is attached to the housing 80 so as to be in contact with the first filtration chamber 30. The rotating member 40 is supported by the housing 80 so as to be rotatable relative to the housing 80. The drive device 13 rotates the rotating member 40. The filtration unit 100 includes a first electrode 31, a second electrode 32, a filter medium 34, and a second filter chamber 35. The first electrode 31 is provided with a plurality of first openings 31b. The second electrode 32 is provided with a plurality of second openings 32b, and is provided opposite one surface of the first electrode 31. The filter medium 34 is provided with a plurality of openings 34b, and is provided between the first electrode 31 and the second electrode 32. The second filter chamber 35 is provided in contact with the surface of the second electrode 32 opposite the filter medium 34. The rotating member 40 includes a third electrode 33 that faces the first electrode 31 with the first filter chamber 30 interposed therebetween.

[0055] According to this, the particles 71 move in a direction from the first electrode 31 to the third electrode 33 due to a repulsive force F (a repulsive force generated between the particles 71 and the first electrode 31) generated on the particles 71 between the first electrode 31 and the third electrode 33. This electrophoresis can suppress the formation of a cake layer on the surface of the first electrode 31 and the surface of the filter medium 34. In addition, the particles 71 can be separated by electroosmosis, which causes the water molecules 73 to move by the electric field between the first electrode 31 and the second electrode 32 and pass through the filter medium 34, and the concentration of the particles 71 in the slurry (raw liquid) 70 in the first filter chamber 30 can be increased. This can improve the filtration speed by several times to ten times or more compared to a method in which pressure is simply applied to the slurry (raw liquid) 70 to separate particles 71 having a particle size larger than the mesh openings 34b of the filter medium 34. Furthermore, the flow of the slurry (raw liquid) 70 in the first filter chamber 30 is promoted by the rotation of the rotating member 40 including the third electrode 33. Therefore, compared to the case where pressure is simply applied to the slurry (raw liquid) 70 in the first filtration chamber 30, the filtration speed can be further improved.

[0056] In the filtration unit 100, the first electrode 31, the second electrode 32, and the filter material 34 are provided on both sides of the second filter chamber 35.

[0057] This allows one set of the first electrode 31, the second electrode 32, and the filter medium 34 and the other set of the first electrode 31, the second electrode 32, and the filter medium 34 to share one second filter chamber 35. Therefore, the filtration device 10 can achieve both an increase in the filtration area and a reduction in size.

[0058] Moreover, in the filtration device 10, the rotating member 40 includes a shaft 41 and a plurality of flanges 43 provided on the outer circumferential surface of the shaft 41. The flange 43 includes an attachment portion 431 to which the third electrode 33 is attached, and a disk-shaped stirring portion 433 having a plurality of grooves 434 on its surface facing the first filtration chamber 30.

[0059] According to this, the slurry (undiluted liquid) 70 in the first filtration chamber 30 enters the grooves 434. When the rotating member 40 rotates, the slurry (undiluted liquid) 70 that has entered the grooves 434 is pushed out. This promotes the flow of the slurry (undiluted liquid) 70 in the first filtration chamber 30. Therefore, the filtration device 10 can further improve the filtration speed.

[0060] In the filtration device 10, the grooves 434 include a first groove 435 provided on one surface of the stirring section 433 in the axial direction parallel to the rotation axis R of the rotating member 40, and a second groove 436 provided on the other surface of the stirring section 433 in the axial direction. When viewed from the axial direction, the first groove 435 describes a circular arc that is convex in the opposite direction to the rotation direction DR of the rotating member 40. The second groove 436 describes a circular arc that is convex in the rotation direction DR of the rotating member 40.

[0061] According to this, the slurry (undiluted liquid) 70 flows radially inward in the portion of the first filter chamber 30 on one side of the flange 43, and the slurry (undiluted liquid) 70 flows radially outward in the portion of the first filter chamber 30 on the other side of the flange 43. This promotes the flow of the slurry (undiluted liquid) 70 in the first filter chamber 30. Therefore, the filtration device 10 can further improve the filtration speed.

[0062] In the filtration device 10, the absolute value of the second potential V2 of the second electrode 32 is greater than the absolute value of the first potential V1 of the first electrode 31. The potential difference between the first potential V1 and the third potential V3 of the third electrode 33 is greater than the potential difference between the first potential V1 and the second potential V2.

[0063] According to this, even if the distance between the first electrode 31 and the third electrode 33, which face each other across the first filtration chamber 30, is greater than the distance between the first electrode 31 and the second electrode 32, the particles 71 can be effectively moved toward the third electrode 33 by electrophoresis.

[0064] (Embodiment 2) Fig. 13 is a cross-sectional view of the filtration device according to the second embodiment. Fig. 14 is a front view of the filtration device according to the second embodiment. Fig. 15 is a cross-sectional view of the filtration device according to the second embodiment in a state in which the rotation axis is parallel to the vertical direction. As shown in Fig. 13, the filtration device 10 according to the embodiment includes a housing 80, a first filtration chamber 30, a supply unit 81, a discharge unit 83, a rotating member 40, a drive device 13, and a plurality of filtration units 100. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof may be omitted.

[0065] As shown in FIG. 13, the housing 80 is a member that supports the rotating member 40 and the filtering unit 100. The housing 80 has a space inside. The housing 80 can accommodate the rotating member 40 and the filtering unit 100 inside. The housing 80 is fixed to a base 200 placed on an installation surface 300. As shown in FIG. 14 and FIG. 15, the attitude of the housing 80 with respect to the base 200 is changeable. As shown in FIG. 14, the housing 80 is connected to the base 200 via a rotation support mechanism 250. The rotation support mechanism 250 is fixed to the base 200 and supports the housing 80 so that the housing 80 can rotate around a horizontal rotation axis. As shown in FIG. 2, the housing 80 includes a third connecting conductor 853 and a brush 854. The third connecting conductor 853 is conductive. The third connecting conductor 853 is attached to one end of the housing 80. The brush 854 is conductive and connected to the third connecting conductor 853. As shown in FIG. 3, the first filter chamber 30 is the internal space of the housing 80 .

[0066] As shown in FIG. 13, the supply unit 81 is attached to the housing 80. A gap between the supply unit 81 and the housing 80 is sealed by a sealing member. The supply unit 81 supplies a slurry (undiluted liquid) to the first filtration chamber 30. As shown in FIG. 5, the supply unit 81 includes a supply port 811 which is an opening provided on the outer circumferential surface. A pipe is connected to the supply port 811. The slurry (undiluted liquid) pressurized by a pressurizing device or the like is supplied to the first filtration chamber 30 via the pipe and the supply port 811.

[0067] As shown in FIG. 13, the discharge unit 83 is attached to the housing 80. A gap between the discharge unit 83 and the housing 80 is sealed by a seal member. The discharge unit 83 discharges the concentrated slurry (undiluted liquid) in the first filtration chamber 30 to the outside. As shown in FIG. 5, the discharge unit 83 has a concentrated liquid discharge port 831 which is an opening provided on the outer circumferential surface. A pipe is connected to the concentrated liquid discharge port 831. Due to the pressure difference between the inside and the outside of the first filtration chamber 30, the concentrated slurry (undiluted liquid) in the first filtration chamber 30 is discharged to the outside through the concentrated liquid discharge port 831 and the pipe. Note that a pressure reducing device such as a vacuum pump may be provided in the pipe connected to the concentrated liquid discharge port 831.

[0068] The rotating member 40 is disposed inside the housing 80. The rotating member 40 is supported by the housing 80. The rotating member 40 can rotate relative to the housing 80. The rotating member 40 rotates about a rotation axis R. The rotation axis R is parallel to the horizontal direction. In FIG. 13, the left-right direction of the paper is the horizontal direction. In the following description, the direction parallel to the rotation axis R is described as the axial direction. The direction parallel to a straight line perpendicular to the rotation axis R is described as the radial direction. The direction along the circumference centered on the rotation axis R is simply described as the circumferential direction. In FIG. 13, the rotation axis R is parallel to the horizontal direction. In FIG. 15, the rotation axis R is parallel to the vertical direction.

[0069] The rotating member 40 includes a shaft 41, a plurality of flanges 43, and a third electrode 33. The shaft 41 is a rod-shaped member. The shaft 41 is connected to the driving device 13. A gap between the shaft 41 and the housing 80 is sealed by a seal member.

[0070] The flanges 43 are provided on the outer peripheral surface of the shaft 41. The flanges 43 contact the first filtration chamber 30. Each flange 43 is disposed between two filtration units 100 arranged in the axial direction. In the first filtration chamber 30, the flanges 43 and the filtration units 100 are arranged alternately along the axial direction. The flanges 43 are formed in a substantially disk shape. The flange 43 closest to the supply unit 81 among the plurality of flanges 43 overlaps with the supply unit 81 when viewed from the radial direction. The flange 43 closest to the discharge unit 83 among the plurality of flanges 43 overlaps with the discharge unit 83 when viewed from the radial direction.

[0071] 7, when viewed from the axial direction, the first groove 435 describes a circular arc that is convex in the opposite direction to the rotation direction DR of the rotating member 40. Therefore, when the rotating member 40 rotates, the slurry (undiluted liquid) in contact with the first groove 435 is guided radially inward (toward the shaft 41). That is, the slurry (undiluted liquid) between the first groove 435 and the filtration unit 100 is guided radially inward.

[0072] The second groove 436 is disposed on the other of the two surfaces of the stirring portion 433 facing the axial direction. That is, the second groove 436 is disposed on the back side of the first groove 435. The second grooves 436 are disposed at equal intervals along the circumferential direction. As shown in FIG. 8, the first groove 435, when viewed from the axial direction, describes a circular arc that is convex toward the rotation direction DR of the rotating member 40. Therefore, when the rotating member 40 rotates, the slurry (raw liquid) in contact with the second groove 436 is guided to the outside in the radial direction (the side opposite to the shaft 41 side). That is, the slurry (raw liquid) between the second groove 436 and the filtration unit 100 is guided to the outside in the radial direction.

[0073] The slurry (undiluted liquid) guided radially inward by the first groove 435 moves axially through the gap between the inner circumferential surface of the filtration unit 100 and the outer circumferential surface of the shaft 41. Thereafter, the slurry (undiluted liquid) guided radially outward by the second groove 436 moves axially through the gap between the inner circumferential surface of the housing 80 and the outer circumferential surface of the flange 43. By repeating the above-mentioned movement, the slurry (undiluted liquid) advances from the supply unit 81 to the discharge unit 83 in the meandering flow path formed between the rotating member 40 and the filtration unit 100.

[0074] As shown in FIG. 13, a plurality of filtration units 100 are attached to the housing 80. All of the filtration units 100 are disposed between the supply unit 81 and the discharge unit 83. In the state shown in FIG. 13, the plurality of filtration units 100 are disposed side by side along the horizontal direction. That is, the rotation axis R is parallel to the horizontal direction. In the state shown in FIG. 15, the plurality of filtration units 100 are disposed side by side along the vertical direction. That is, the rotation axis R is parallel to the vertical direction. A portion of one filtration unit 100 is disposed at a position between two flanges 43 of the first filtration chamber 30.

[0075] As described above, the filtration device 10 of the present embodiment includes a housing 80, a first filtration chamber 30, a plurality of filtration units 100, a rotating member 40, and a driving device 13. The first filtration chamber 30 is an internal space of the housing 80. The plurality of filtration units 100 are attached to the housing 80 so as to be in contact with the first filtration chamber 30. The rotating member 40 is supported by the housing 80 so as to be rotatable relative to the housing 80. The driving device 13 rotates the rotating member 40. The filtration unit 100 includes a first electrode 31, a second electrode 32, a filter medium 34, and a second filtration chamber 35. The first electrode 31 is provided with a plurality of first openings 31b. The second electrode 32 is provided with a plurality of second openings 32b, and is provided opposite one surface of the first electrode 31. The filter medium 34 is provided with a plurality of openings 34b, and is provided between the first electrode 31 and the second electrode 32. The second filter chamber 35 is provided in contact with the surface of the second electrode 32 opposite to the filter medium 34. The rotating member 40 includes a third electrode 33 facing the first electrode 31 across the first filter chamber 30. The multiple filtration units 100 are arranged side by side in a direction along the rotation axis R of the rotating member 40.

[0076] According to this, the particles 71 move in a direction from the first electrode 31 to the third electrode 33 due to a repulsive force F (a repulsive force generated between the particles 71 and the first electrode 31) generated on the particles 71 between the first electrode 31 and the third electrode 33. This electrophoresis can suppress the formation of a cake layer on the surface of the first electrode 31 and the surface of the filter medium 34. In addition, the particles 71 can be separated by electroosmosis, which causes the water molecules 73 to move by the electric field between the first electrode 31 and the second electrode 32 and pass through the filter medium 34, and the concentration of the particles 71 in the slurry (raw liquid) 70 in the first filter chamber 30 can be increased. This can improve the filtration speed by several times to ten times or more compared to a method in which pressure is simply applied to the slurry (raw liquid) 70 to separate particles 71 having a particle size larger than the mesh openings 34b of the filter medium 34. Furthermore, the flow of the slurry (raw liquid) 70 in the first filter chamber 30 is promoted by the rotation of the rotating member 40 including the third electrode 33. Therefore, compared to the case where pressure is simply applied to the slurry (raw liquid) 70 in the first filtration chamber 30, the filtration speed can be further improved.

[0077] In one filtration unit 100, the first electrode 31, the second electrode 32, and the filter medium 34 are provided on both sides of the second filter chamber 35.

[0078] This allows one set of the first electrode 31, the second electrode 32, and the filter medium 34 and the other set of the first electrode 31, the second electrode 32, and the filter medium 34 to share one second filter chamber 35. Therefore, the filtration device 10 can achieve both an increase in the filtration area and a reduction in size.

[0079] Moreover, in the filtration device 10, the rotating member 40 includes a shaft 41 and a plurality of flanges 43 provided on the outer circumferential surface of the shaft 41. The flange 43 includes an attachment portion 431 to which the third electrode 33 is attached, and a disk-shaped stirring portion 433 having a plurality of grooves 434 on its surface facing the first filtration chamber 30.

[0080] According to this, the slurry (undiluted liquid) 70 in the first filtration chamber 30 enters the grooves 434. When the rotating member 40 rotates, the slurry (undiluted liquid) 70 that has entered the grooves 434 is pushed out. This promotes the flow of the slurry (undiluted liquid) 70 in the first filtration chamber 30. Therefore, the filtration device 10 can further improve the filtration speed.

[0081] In the filtration device 10, the filtration units 100 and the flanges 43 are arranged alternately in a direction along the rotation axis R of the rotating member 40.

[0082] According to this, a meandering flow path is formed between the rotating member 40 and the filtration unit 100. This makes it easier to increase the contact area of ​​the slurry (raw liquid) 70 with the filtration unit 100. Therefore, the filtration device 10 can further improve the filtration speed.

[0083] In the filtration device 10, the grooves 434 include a first groove 435 provided on one surface of the stirring section 433 in the axial direction parallel to the rotation axis R of the rotating member 40, and a second groove 436 provided on the other surface of the stirring section 433 in the axial direction. When viewed from the axial direction, the first groove 435 describes a circular arc that is convex in the opposite direction to the rotation direction DR of the rotating member 40. The second groove 436 describes a circular arc that is convex in the rotation direction DR of the rotating member 40.

[0084] According to this, the slurry (undiluted liquid) 70 flows radially inward in a portion of the first filtration chamber 30 on one side of the flange 43, and the slurry (undiluted liquid) 70 flows radially outward in a portion of the first filtration chamber 30 on the other side of the flange 43. This promotes the flow of the slurry (undiluted liquid) 70 in the first filtration chamber 30. Specifically, the slurry (undiluted liquid) 70 is more likely to move from the supply unit 81 toward the discharge unit 83 through the meandering flow path formed between the rotating member 40 and the filtration unit 100. Therefore, the filtration device 10 can further improve the filtration speed.

[0085] In the filtration device 10, the absolute value of the second potential V2 of the second electrode 32 is greater than the absolute value of the first potential V1 of the first electrode 31. The potential difference between the first potential V1 and the third potential V3 of the third electrode 33 is greater than the potential difference between the first potential V1 and the second potential V2.

[0086] According to this, even if the distance between the first electrode 31 and the third electrode 33, which face each other across the first filtration chamber 30, is greater than the distance between the first electrode 31 and the second electrode 32, the particles 71 can be effectively moved toward the third electrode 33 by electrophoresis.

[0087] In the filtration device 10, the multiple filtration units 100 are arranged side by side in the vertical direction.

[0088] This allows the slurry (raw liquid) 70 to easily move from the supply unit 81 to the discharge unit 83 by gravity through the meandering flow path formed between the rotating member 40 and the filtration unit 100. Therefore, the filtration device 10 can further improve the filtration speed.

[0089] The above-described embodiment is for facilitating understanding of the present disclosure, and is not intended to limit the present disclosure. The present disclosure may be modified or improved without departing from the spirit of the present disclosure, and equivalents thereof are also included in the present disclosure. [Explanation of symbols]

[0090] 10 Filtration equipment 13 Drive unit 30 First Chamber 31 1st electrode 31a, 32a Conductive thin wire 31b 1st opening 32 2nd electrode 32b 2nd opening 33 Third electrode 34 Filter media 34b Opening 35 Second Chamber 40 Rotating member 41 Shaft 43 Flange 43a First flange 43b Second flange 51 1st power supply 52 2nd power supply 53 Third power supply 70 Slurry (undiluted) 71 particles 72 liquid 73 Water molecules 74 Chromoproteins 75 Filtrate 80 Housing 81 Supply Unit 83 Discharge unit 100 Filtration Unit 101 First connecting conductor 102 Second connecting conductor 105 Filtrate outlet 110 cases 412 Internal conductor 431 Mounting part 433 Stirring section 434 Groove 435 First groove 436 Second groove 437 Internal Conductor 811 Supply Inlet 831 Concentrate outlet 853 Third connecting conductor 854 Brush R rotation axis DR Rotation direction

Claims

1. Housing and A first filter chamber which is an internal space of the housing; a filtration unit attached to the housing so as to contact the first filtration chamber; a rotating member supported by the housing so as to be rotatable relative to the housing; A drive device that rotates the rotating member; Including, The filtration unit comprises: a first electrode having a plurality of first openings; a second electrode having a plurality of second openings and facing one surface of the first electrode; a filter medium having a plurality of openings and disposed between the first electrode and the second electrode; a second filter chamber provided in contact with a surface of the second electrode opposite to the filter medium; Including, The rotating member includes a third electrode facing the first electrode across the first filter chamber. Filtration equipment.

2. In the filtration unit, the first electrode, the second electrode, and the filter medium are provided on both sides of the second filter chamber. The filtration device of claim 1 .

3. The filter unit includes a plurality of the filter units, The plurality of filtration units are arranged in a line along the rotation axis of the rotating member. The filtration device of claim 1 .

4. The plurality of filtration units are arranged in a vertical direction. The filtration device according to claim 3.

5. The rotating member includes a shaft and a plurality of flanges provided on an outer circumferential surface of the shaft, The flange includes an attachment portion to which the third electrode is attached, and a disk-shaped stirring portion having a plurality of grooves on a surface thereof facing the first filtration chamber. The filtration device according to claim 2.

6. The groove includes a first groove provided on one surface of the stirring portion in an axial direction parallel to the rotation axis of the rotating member, and a second groove provided on the other surface of the stirring portion in the axial direction, When viewed from the axial direction, the first groove describes a circular arc that is convex in a direction opposite to a rotation direction of the rotating member, and the second groove describes a circular arc that is convex in a rotation direction of the rotating member. The filtration device according to claim 5.

7. The filtration units and the flanges are arranged alternately in a direction along the rotation axis of the rotating member. The filtration device according to claim 5.

8. A target processing liquid containing particles to be separated and liquid is supplied to the first filtration chamber, A first potential is applied to the first electrode, the first potential having the same polarity as the polarity of the particles; A second potential having the same polarity as the polarity of the particles and an absolute value different from the absolute value of the first potential is supplied to the second electrode. A filtration device according to any one of claims 1 to 7.

9. a first power supply that supplies the first electrode with the first potential having the same polarity as the polarity of the particles; a second power supply that supplies the second electrode with the second potential having the same polarity as the polarity of the particles; The third electrode is connected to a reference potential. The filtration device according to claim 8.

10. a first power supply that supplies the first electrode with the first potential having the same polarity as the polarity of the particles; a second power supply that supplies the second electrode with the second potential having the same polarity as the polarity of the particles; and a third power supply that supplies a third potential having a polarity different from that of the particles to the third electrode. The filtration device according to claim 8.

11. the absolute value of the second potential is greater than the absolute value of the first potential; a potential difference between the first potential and the third potential is greater than a potential difference between the first potential and the second potential; The filtration device of claim 10.

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