WO2004091756A1

WO2004091756A1 - Ceramics honeycomb filter and method of manufacturing the same

Info

Publication number: WO2004091756A1
Application number: PCT/JP2004/001763
Authority: WO
Inventors: Tomonori Ito; Tatsuo Baba
Original assignee: Ngk Insulators, Ltd.
Priority date: 2003-04-10
Filing date: 2004-02-18
Publication date: 2004-10-28
Also published as: JP3868391B2; JP2004305993A

Abstract

A ceramics honeycomb filter (1), comprising a plurality of membrane filtration cells (4) separated from each other through a porous ceramics partition wall (2), having filtration membranes (3) disposed therein, and forming flow passages for filtrated fluid, a plurality of water collecting cells (5) separated from each other through the partition wall (2), positioned adjacent to the specified membrane filtration cells (4) through the partition wall (2), and forming the flow passages for the filtrated fluid produced by filtrating the fluid to be filtrated by the filtration membranes (3), an outer wall (6) surrounding the membrane filtration cells (4) and the water collecting cells (5), water collecting slits (7) passed from one portions of the outer wall (6) to the other portions of the outer wall (6) through the water collecting cells (5) at the positions of the outer wall (6) apart specified distances from both end parts of the water collecting cells (5) for flowing out the filtrated fluid passed through the water collecting cells (5) to the outside, and porous sealing member (8) filled in spaces ranging from the end faces of the water collecting cells to the water collecting slits (7). The ceramics honeycomb filter can supply the filtrated fluid with high cleanliness by effectively preventing the fluid to be filtrated and the filtrated fluid from accumulating therein.

Description

Specification

Ceramic honeycomb filter and method for manufacturing the same

The present invention relates to a ceramic honeycomb filter and a method for manufacturing the same. More specifically, the present invention relates to a ceramic honeycomb filter capable of effectively preventing a fluid to be filtered and a filtration fluid from staying inside and supplying a high-purity filtration fluid, and a method for manufacturing the same. Background art

In recent years, a ceramic honeycomb filter having cells partitioned by porous partition walls has been used as a filter for solid-liquid separation or gas-solid separation. This ceramic honeycomb filter has better physical strength, durability, corrosion resistance, etc. than organic polymer films used for similar applications. In a wide range of fields such as the field, it is suitably used for removing suspended substances, bacteria, dust and the like in liquids and gases.

In such a ceramic honeycomb filter, as shown in Fig. 3, from the viewpoint of increasing the water flow rate and improving the filtration performance, a large number of parallel-shaped porous bodies formed in the longitudinal direction of the cylindrical porous body were used. In order to increase the amount of water flowing from the flow passage near the center of the porous body, a filter membrane 22 having a smaller diameter than the porous body is formed on the inner peripheral surface of the flow path (cell) 21. In addition, a slit-like void (water collecting slit) 23 is provided in the longitudinal direction of the porous body, and a flow path (water collecting cell) 21 communicating with the void (water collecting slit) 23 is formed at one end of a 2 a. Is sealed by a clogging member 24, and the fluid to be filtered supplied to the flow path (membrane filtration cell) 21b in which the filtration membrane 22 is formed is filtered by the filtration membrane 22. A flow passage (water collecting cell) whose end is sealed with a clogging member 24 Ritsuto) 2 3 ceramic honeycomb fill evening 2 0 capable of flowing out to the outside via has been proposed (e.g., JP-2 0 0 0 1 5 3 1 1 7 JP).

In the above-described ceramic honeycomb filter 20, the filtration membrane 22 is formed. This improves filtration performance, and the provision of voids (water collection slits) 23 increases the flow rate.

However, in the above-described ceramic honeycomb filter, the clogging member 24 that seals the end of the flow passage (water collecting cell) 21a simply has a structure in which the fluid to be filtered is merely a flow passage (water collecting cell) 21a. It was only recognized that it would be enough to prevent intrusion into the interior, and when the clogging member 24 was filled too deeply, the flow passage (collection cell) 21 a was filled Since the clogging member 24 protrudes from the gap (water collection slit) 23 and causes troubles and repairs, it is necessary to reach only the minimum necessary position where the inflow of the fluid to be filtered can be prevented. Was not filled. Therefore, in the flow passage (water collecting cell) 2 la, between the end of the clogging member 24 and the gap (water collecting slit) 23, the portion where the filtered fluid to be discharged stays (the liquid reservoir) 2) 25 were formed.

For this reason, there has been a problem that a part of the filtration fluid stays in the above-mentioned liquid reservoir 25 and bacteria and the like propagate, and contaminate the entire filtration fluid. In addition, the ceramic honeycomb filter 20 may be periodically cleaned using a chemical solution. However, the chemical solution used for this cleaning stays in the above-described liquid pool 25 and the ceramic honeycomb film 20 starts cleaning. It was not possible to completely remove the solution, and the accumulated drug solution gradually diffused and contaminated the filtered fluid. In addition, as shown in FIG. 4, in the step of forming the filtration membrane 22 constituting the ceramic honeycomb filter 20, the filtration membrane slurry containing a solid component to become the filtration membrane 22 is reduced to a predetermined pressure under reduced pressure. Flowed into the flow channel (membrane filtration cell) 21b, solid components 22a contained in the poured filtration membrane slurry are attached to the inner surface of the flow channel (membrane filtration cell) 21b, and then dried under atmospheric pressure After the solid components 22a are removed, the water 22b of the filtration membrane slurry stays in the above-mentioned liquid pool 25, and is restored to the atmospheric pressure after the film formation is completed. The water 22 b of the filtration membrane slurry moves through the partition wall 26 and lifts and separates the filtration membrane 22 that has just adhered to the inner surface of the flow passage (membrane filtration cell) 21 b. There was a problem. '' Disclosure of the Invention SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has a ceramic honeycomb filter capable of effectively preventing a fluid to be filtered and a filtration fluid from staying inside and supplying a high-purity filtration fluid. A method for manufacturing the same is provided.

In order to achieve the above object, the present invention provides the following ceramic honeycomb filter and a method for manufacturing the same.

[1] A plurality of membrane filtration cells serving as flow paths for a fluid to be filtered, which are partitioned by a porous partition wall made of ceramics, and a filtration membrane is disposed inside the partition wall; A plurality of water collection cells adjacent to the predetermined membrane filtration cell with the partition wall interposed therebetween, the plurality of water collection cells serving as a flow path of the filtration fluid in which the fluid to be filtered is filtered by the filtration membrane; and the membrane filtration cell and the water collection cell An outer wall surrounding the outer wall, and a portion separated by a predetermined length from both ends of each of the water collecting cells on the outer wall for allowing the filtered fluid that has passed through the water collecting cell to flow outside. And a water collecting slit penetrating through the water collecting cell from the part of the water collecting cell to the other part of the outer wall, and filled in a space from each end face of the water collecting cell to the water collecting slit. With a porous clogging member Ceramics honeycomb fill evening.

[2] The ceramic honeycomb filter according to the above [1], wherein the clogging member is formed of a porous body having a plurality of communication holes.

[3] The ceramic honeycomb fill according to [1] or [2], wherein the clogging member is formed from a porous material including at least one material selected from the group consisting of alumina, mullite, selven, and cordierite. evening.

[4] The ceramic honeycomb filter according to [2] or [3], wherein each of the plurality of communication holes formed in the clogging member has a portion having a hole diameter of 20 zm or less.

[5] The ceramic honeycomb filter according to any one of [1] to [4], wherein the porosity of the plugging member is 25 to 50%.

[6] The ceramic honeycomb filter according to any of [1] to [5], wherein the thermal expansion coefficient of the clogging member is lower than or equal to the f¾ expansion coefficient of the partition.

[7] Each of the plurality of membrane filtration cells having a cross section perpendicular to the flow direction of the fluid to be filtered has a circular, elliptical, oval, triangular, quadrangular, pentagonal, hexagonal, The ceramic honeycomb filter according to any one of the above [1] to [6], wherein the ceramic honeycomb filter has at least one shape selected from the group consisting of a heptagon.

[8] The shape of each of the plurality of water collection cells having a cross section perpendicular to the flow direction of the filtration fluid is from a circle, an ellipse, an oval, a triangle, a square, a pentagon, a hexagon, and a heptagon. The ceramic honeycomb filter according to any one of the above [1] to [7], which has at least one shape selected from the group consisting of:

[9] The raw material is extruded to obtain an unsintered filter molded body having a predetermined shape having cells serving as flow paths for the fluid to be filtered and the filtered fluid. An unsintered filter molded body with a water collecting slit is obtained by forming a water collecting slit that penetrates the predetermined cell from one part and communicates with the other part to obtain an unsintered filter molded body with the water collecting slit. A body is filled with a clogging material from each end face of the predetermined cell to the water collecting slit penetrating the predetermined cell to obtain a plugged material-filled unfired filled rubber molded body. Calcining the obtained plugged material-filled unfired filter molded product to obtain a plugged material-filled filter molded product, and the inner peripheral surface of the predetermined cell constituting the obtained plugged material-filled filter molded product Baking after forming a filtration membrane Manufacturing method of La mix honeycomb filter.

[10] The method for producing a ceramic honeycomb filter according to the above [9], wherein the plugging material includes an aggregate particle, an inorganic binder, a binder, a thickener, and a water retention agent.

[11] The ceramic honeycomb filler according to [10], wherein the binder constituting the plugging material is contained in an amount of 0.08 to 0.12 parts by mass with respect to 100 parts by mass of the aggregate particles. Production method.

[12] The method according to [10] or [11], wherein the thickener constituting the plugging material is contained in an amount of 0.04 to 0.1 part by mass with respect to 100 parts by mass of the aggregate particles. Manufacturing method of Sera Mix Honeycomb Filler.

[13] The ceramic according to any of [10] to [12], wherein the water retaining agent constituting the plugging material is contained in an amount of 5 to 6 parts by mass based on 100 parts by mass of the aggregate particles. Manufacturing method of Kus Honeycomb Fill.

[14] After forming the filtration membrane on the plugging material-filled filter molded body, The method for producing a ceramic honeycomb filter according to any one of the above [9] to [13], wherein the end face is cut by a predetermined length.

[15] The above-mentioned [10] to [14], wherein the aggregate particles constituting the plugging material are at least one compound selected from the group consisting of alumina, mullite, celene, and cordierite. The method for producing a ceramic honeycomb fill according to any one of the above.

[16] The inorganic binder described in [10] to [10], wherein the inorganic binder constituting the plugging material is at least one compound selected from the group consisting of alumina, silica, zirconia, glass frit, feldspar, and cordierite. 15] The method for producing a ceramic honeycomb filter according to any one of [1] to [5].

[17] The method according to any one of [10] to [16], wherein the binder constituting the filling material is at least one compound selected from the group consisting of polyvinyl alcohol, polyethylene glycol, starch, and clay. A method for producing the ceramic honeycomb filter described in the above.

As described above, the ceramic honeycomb filter of the present invention can effectively prevent the fluid to be filtered and the filtration fluid from staying inside, and can supply the filtration fluid with high cleanliness. BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1 (a) and 1 (b) are explanatory views schematically showing one embodiment of the ceramic honeycomb filter of the present invention, and FIG. 1 (a) shows a part of the ceramic honeycomb filter. FIG. 1 (b) is a cross-sectional view cut along a plane including the central axis.

2 (a) and 2 (b) are cross-sectional views showing a step of filling a predetermined cell with a plugging material in one embodiment of the method for manufacturing a ceramic honeycomb filter according to the present invention. .

FIG. 3 is a cross-sectional view schematically showing a conventional ceramic honeycomb filter. FIG. 4 is a cross-sectional view showing a step of filling a predetermined cell with a plugging material in a conventional method for manufacturing a ceramic honeycomb filter. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the ceramic honeycomb filter and the method for manufacturing the same according to the present invention will be specifically described with reference to the drawings.

1 (a) and 1 (b) are explanatory views schematically showing one embodiment of the ceramic honeycomb filter of the present invention, and FIG. 1 (a) is a part of the ceramic honeycomb filter. FIG. 1 (b) is a cross-sectional view taken along a plane including the central axis. As shown in FIGS. 1 (a) and 1 (b), the ceramic honeycomb filter 1 of the present embodiment is divided by a porous partition wall 2 made of ceramics, and a filtration membrane 3 is provided therein. A plurality of membrane filtration cells 4 serving as flow paths for the fluid to be filtered, and a plurality of membrane filtration cells 4 which are partitioned by the partition walls 2 and are adjacent to the predetermined membrane filtration cells 4 with the partition walls 2 interposed therebetween. A plurality of water collection cells 5 that serve as a flow path of the filtration fluid filtered by the membrane 3, an outer wall 6 surrounding the membrane filtration cells 4 and the water collection cells 5, and a filtration fluid that has passed through the water collection cells 5 flows out to the outside. At a predetermined distance from both ends of the water collecting cell 5 on the outer wall 6 to communicate with one part of the outer wall 6 through the water collecting cell 5 to other parts of the outer wall 6. Reaching the slit 7 from the water collecting slit 7 and each end of the collecting cell It is obtained by a clogging member 8 of the filled porous space in. In FIG. 1 (a), a columnar ceramic honeycomb filter 1 is shown, but the shape of the ceramic honeycomb filter 1 of the present embodiment is not limited to a columnar shape, and is not limited to a central axis. The shape of the cross section in the vertical plane may be a columnar shape such as a quadrangle.

In the ceramic honeycomb filter 1 of the present embodiment, the fluid to be filtered flows into the inside of the membrane filtration cell 4 from the end face, and passes through the filtration membrane 3 disposed inside the membrane filtration cell 4. The fluid to be filtered is filtered, and the filtered fluid that has been filtered by the filtration membrane 3 flows into the water collecting cell 5 via the porous partition wall 2 and is collected from the water collecting cell 5 through the water collecting cell 5. The water flows into the water slit 7 and flows out of the water collecting slit 7 formed in the outer wall 6 to the outside. Further, a configuration may be adopted in which a part of the filtration fluid filtered by the filtration membrane 3 does not flow into the water collecting cell 5 from the partition 2 but flows out through the outer wall 6 to the outside. Thus, the present embodiment The ceramic honeycomb filter 1 of the present embodiment has a configuration including the water collecting slits 7 so that the water flow resistance is reduced and the ceramic honeycomb filter 1 has excellent water permeability. Also, in a conventional ceramic honeycomb filter provided with a water collecting cell, a portion of the water collecting cell in which the filtered fluid to flow out stagnates between the end of the clogging member and the water collecting slit (liquid reservoir). When some of the filtration fluid stays in the liquid pool, various bacteria and the like propagate and contaminate the entire filtration fluid, and the chemical used for cleaning the ceramic honeycomb filter becomes in the liquid pool. There has been a problem that the retained chemical liquid gradually diffuses and contaminates the filtration fluid, but the ceramic honeycomb filter 1 of the present embodiment has a problem that the clogging member 8 Since the space from each end face to the water collecting slit 7 is filled, a portion where the filtration fluid or the chemical solution stays is not formed, and the filtration fluid is not contaminated. No.

Further, in the ceramic honeycomb filter 1 of the present embodiment, the fluid to be filtered flows directly from the partition 2 at the end face of the ceramic honeycomb filter 1 and is filtered by the filtration membrane 3 on the inner surface of the membrane filtration cell 4. In order to prevent the ceramic honeycomb fill 1 from flowing out without being sealed, a seal portion 9 is formed so as to cover the partition 2 at the end face of the ceramic honeycomb fill 1. The seal portion 9 is formed by applying a glaze such as silica glass to the end face of the ceramic honeycomb filter 1 and firing the same. In the present embodiment, it is preferable to appropriately set the position where the water collecting slit 7 is formed and the shape of the opening thereof according to the size of the ceramic honeycomb filter 1. For example, the shape of the ceramic honeycomb filter 1 Is cylindrical, its end face diameter is 180 mm and its axial length is 100 mm, the shape of the opening of the water collecting slit 7 formed in the outer wall 6 is one side Preferably, the length is 20 to 80 mm, which is oval, square or rectangular.

In the ceramic honeycomb filter 1 of the present embodiment, the clogging member 8 is filled in the space from each end face of the water collecting cell 5 to the water collecting slit 7, but in this embodiment, The phrase "filled in the space from each end face of the water collecting cell 5 to the water collecting slit 7" means that the water collecting cell 5 is filled from the viewpoint of accuracy when filling the clogging member 8. Clogging member 8 in the range of 80 to 100% from each end face of water collection cell 5 in the space from each end face of Is filled. With such a configuration, the ceramics 82 cam filter 1 can effectively prevent the fluid to be filtered and the filtration fluid from staying inside, and can supply a highly purified filtration fluid.

The partition wall 2 of the ceramic honeycomb fill 1 according to the present embodiment is made of, for example, a kneaded clay obtained by mixing an aggregate binder and an inorganic binder with an organic binder such as methylcellulose, a dispersant, and water. It can be formed by extrusion molding with a honeycomb molding machine. As the aggregate particles, at least one compound selected from the group consisting of alumina, mullite, selven, and cordierite can be suitably used. As the inorganic binder, at least one compound selected from the group consisting of alumina, silica, zirconia, titania, glass frit, feldspar, and cordierite can be suitably used.

For the clogging member 8 used in the present embodiment, the same material as that of the partition wall 2 described above can be suitably used, and for example, at least one selected from the group consisting of alumina, mullite, selben, and coalite It is preferably formed from a porous material containing one material. The plugging material (plugging material slurry) used in the manufacturing process includes the plugging member 8 in the ceramics 82 cam filter 1 obtained from each end face of the water collecting cell 5 to the water collecting slit 7. It is preferable to use a material to which a binder, a thickener and a water retention agent are further added so that is filled. The configuration of the plugging material (plugging material slurry) will be specifically described when a method for manufacturing a ceramic honeycomb filter is described.

Further, the clogging member 8 is preferably coarse enough to discharge moisture contained in the filtration membrane slurry used when forming the filtration membrane 3, and more specifically, a plurality of communication holes are formed. It is preferable to be constituted by the formed porous body. Further, when the clogging member 8 is formed of a porous body having a plurality of communication holes formed therein, it is preferable that each of the plurality of communication holes has a portion having a hole diameter of 20 zm or less. In the present embodiment, it is preferable that the porosity of the clogging member 8 is 25 to 50%. When each of the plurality of communication holes does not have a portion having a hole diameter of 20 zm or less and / or when the porosity of the clogging member 8 exceeds 50%, the filtration membrane 3 is formed. The solid component contained in the filtration membrane slurry used for It may pass through and enter the water collection cell 5. If the porosity is less than 25%, it may be difficult to discharge water contained in the filtration membrane slurry used for forming the filtration membrane 3. In addition, the communication hole in the present embodiment is a pore communicating from one part of the surface of the clogging member 8 to another part. Further, it is preferable that the clogging member 8 is uniformly filled so that there is no void whose volume exceeds 0.065 mm ³ . The volume 0. 0 6 5 If there are gaps in excess of mm ^3, when cutting the defective portion at the end of the ceramic eighty-two Kamufiru evening 1, sometimes irregularities are formed on the cut surface. If the end face of the ceramic honeycomb filter 1 has irregularities, it may be difficult to uniformly apply glaze or the like when forming the seal portion 9. The porosity can be measured by a mercury intrusion method.

Further, it is preferable that the coefficient of thermal expansion of the clogging member 8 is lower than or equal to the coefficient of thermal expansion of the partition 2. If the coefficient of thermal expansion of the clogging member 8 is larger than the coefficient of thermal expansion of the partition 2, the clogging member 8 may expand during firing, and the partition 2 may be damaged.

Further, in the present embodiment, a case is shown where each of the cross-sections of the plurality of membrane filtration cells 4 perpendicular to the flow direction of the fluid to be filtered is a circle, but the shape of the membrane filtration cell 4 is The shape is not limited to this, and for example, is preferably at least one shape selected from the group consisting of a circle, an ellipse, an oval, a rectangle, a rectangle, a pentagon, a hexagon, and a heptagon. Further, although the case where each of the cross-sections of the plurality of water collection cells 5 perpendicular to the flow direction of the fluid to be filtered is circular is shown, the shape of the water collection cells 5 is not limited to this. For example, the shape is preferably at least one selected from the group consisting of a circle, an ellipse, an oval, a triangle, a rectangle, a pentagon, a hexagon, and a heptagon.

Further, the filtration membrane 3 disposed inside the membrane filtration cell 4 preferably contains titania, alumina, or both. The filtration membrane 3 has an average pore diameter smaller than the average pore diameter of the partition walls 2, and for example, preferably has an average pore diameter of 0.1 to 1.0 / zm. Although not shown, in the present embodiment, the filtration membrane is an intermediate membrane having an average pore diameter in the middle between the partition wall and the upper filtration membrane, wherein the filtration membrane is an upper filtration membrane. Configuration further equipped with It may be.

Next, a method for manufacturing the ceramic honeycomb filter of the present embodiment will be described. First, the raw material is extruded using, for example, a vacuum extruder to obtain an unsintered filter molded body having a predetermined shape and having cells serving as flow paths of the fluid to be filtered and the filtered fluid. The raw materials are described as a preferred material for the partition wall 2 of the ceramic honeycomb filter 1 shown in FIG. 1 (a), by adding an organic binder such as methyl cellulose, a dispersant, and water to the aggregate particles and the inorganic binder. A kneaded clay that is mixed using a kneader or a kneader can be suitably used.

Next, a water collecting slit is formed in the obtained green body from one part of the side surface of the green body through a predetermined cell to communicate with the other part, and the green body with the water collecting slit is formed. Obtain a molded body. For example, the water collecting slit is formed by grooving the outer wall of the part where the water collecting slit is formed at the time of molding, breaking the water collecting cell wall at the outer periphery with a grindstone, and then collecting the water with a jig having a sharp tip. It can be formed by piercing a water cell. The water collecting slit is used as a part for installing a sealing member that separates the fluid to be filtered from the filtered fluid at the end of the ceramic honeycomb filter, which is the final product, when it is installed in water purification equipment. If a defect occurs in the gripping part that grips the end face in the filtration film forming process described later, it is necessary to remove the defective part by a maximum of about 30 mm. In consideration of the occurrence of cracks, it is preferable to form the unsintered filter formed body with the water collecting slit on a side surface about 55 mm away from the end face. The steps so far can be performed according to a conventional method for manufacturing a ceramic honeycomb filter.

Next, as shown in FIGS. 2 (a) and 2 (b), a predetermined cell 1 Fill the space up to the water collecting slit 7 penetrating 2 with the plugging material (plugging material slurry) 13 to obtain a plugged material-filled unfired filter molded body. Specifically, films 11 (masking) of polyester or the like are attached to both end surfaces of the unsintered filter molded body 10 with the water collecting slit, and holes are formed in portions corresponding to predetermined cells 12. Thereafter, the end face of the unsintered filter molded body 10 with the water collecting slit, to which the film 11 is attached, is pressed into a container 14 filled with the clogging material 13 and an air cylinder is further provided. For example, pressurization is performed at ²⁰⁰ kgf / cm ² to fill a predetermined cell 12 with the clogging material.

The plugging material 13 used in the present embodiment includes an aggregate particle, an inorganic binder, and the like, so that the plugging material 13 can be filled in a predetermined cell 12 until it reaches the water collecting slit. It is preferable that the composition contains a binder, a thickener and a water retention agent. As the aggregate particles and the inorganic binder, those similar to the aggregate particles and the inorganic binder used when producing the unfired filter molded body can be suitably used.

The binder that forms the plugging material 13 has the function of increasing the drying strength of the plugging material 13 at the time of drying and preventing the occurrence of cracks during drying, and is made of polyvinyl alcohol, polyethylene glycol, starch, and clay. It is preferably at least one compound selected from the group consisting of: The filler 13 preferably contains 0.08 to 0.12 parts by mass of the binder with respect to 100 parts by mass of the aggregate particles. If the amount of the binder is less than 0.08 parts by mass, cracks may occur when the plugging material 13 is dried. When the amount of the binder exceeds 0.12 parts by mass, the strength of the plugging material 13 is increased, and cracks may be generated in the unsintered filled molded article 10 having the water collecting slit.

The thickening agent constituting the plugging material 13 is made of a filler 1 such that the plugging material 13 can be easily inserted into a predetermined cell 12 of the unsintered filter molded body 10 with a water collecting slit. 3 has the function of developing an appropriate viscosity, and methylcellulose, lipoxyl methylcellulose, and the like can be suitably used. The filler 13 preferably contains the thickener in an amount of 0.04 to 0.1 part by mass with respect to 100 parts by mass of the aggregate particles. If the amount of the thickener is less than 0.04 parts by mass, the plugging material 13 does not enter the predetermined cell 12 smoothly, and it is difficult to fill the plugging material 13 to a predetermined depth. It can be. If the amount of the thickener exceeds 0.1 parts by mass, the depth of the plugging material 13 filled in each cell 12 differs, and the plugging material 13 is uniformly filled to a predetermined depth. Can be difficult.

When filling the plugging material 13, the water retaining agent constituting the plugging material 13 absorbs the water content of the plugging material 13 into the dried green filter molded body 10 with the water collecting slit. It functions to prevent solidification and to allow the clogging material 13 to uniformly penetrate to a predetermined depth. This As the water retention agent, starch, glycerin and the like can be suitably used. The plugging material 13 preferably contains 5 to 6 parts by mass of the water retention agent with respect to 100 parts by mass of the aggregate particles. If the water retention agent is less than 5 parts by mass, when filling the plugging material 13, the moisture of the plugging material 13 is instantaneously absorbed by the unsintered filled molded product 10 with the water collecting slit, and It may not be possible to fill the filling material 13 to the specified depth. If the water retention agent exceeds 6 parts by mass, the plugging material 13 may not be sufficiently dried by drying before firing, and cracks may be generated during firing.

Next, the obtained unfired filter-filled filter molded product is fired, for example, at 900 to 140 ° C. to obtain a filter-filled filter molded product.

Next, a filter membrane is formed on the inner peripheral surface of a predetermined cell constituting the obtained plugged material-filled filter molded body, and then fired. As a method for forming a filtration membrane, for example, when forming a filtration membrane composed of an intermediate membrane and an upper filtration membrane having a smaller pore size than the intermediate membrane, first, an intermediate membrane is formed. Is formed. The interlayer slurry is composed of 100 parts by mass of a ceramic raw material such as alumina, mullite, titania, cordierite, etc., having the same material as the green compact and having an average particle size of 3.2 m. It can be formed by adding 100 parts by mass of water. Further, an inorganic binder for film may be added to the intermediate film slurry in order to increase the film strength after firing. As the inorganic binder for the film, clay, kaolin, titania sol, silica sol, glass frit, or the like can be used, and the addition amount is preferably 5 to 20 parts by mass from the viewpoint of the film strength. When the film strength can be obtained by sintering only with the ceramic raw material, it is not necessary to add an inorganic binder for the film. This intermediate film slurry was formed on the surface of each cell using an apparatus disclosed in Japanese Patent Application Laid-Open No. Sho 61-238338, dried, and then dried at a predetermined firing temperature, for example, 900 It can be sintered at up to 150 ° C. and fixed to a plugging material-filled filter to form an intermediate film.

On the other hand, an upper filtration membrane slurry for forming an upper filtration membrane is formed. The upper-layer filtration membrane slurry is, for example, a ceramic material such as alumina, mullite, titania, cordierite, or the like, having an average particle diameter of 0.4 m and the same material as the unfired filter molded body, or a coefficient of thermal expansion higher than these ceramic materials. It can be formed by adding 100 parts by mass of water to 100 parts by mass of a material having a small content. Also, this upper filtration membrane An inorganic binder for a film may be added to the slurry in order to increase the film strength after firing. As the inorganic binder for the film, clay, kaolin, titania sol, silica sol, glass frit, or the like can be used. The addition amount is preferably 5 to 20 parts by mass from the viewpoint of the film strength. This upper-layer filtration membrane slurry was formed on the surface of the intermediate membrane using an apparatus disclosed in Japanese Patent Application Laid-Open No. Sho 61-238338, dried, and then dried at a predetermined firing temperature 90 °. It can be sintered at 0 to 150 ° C. and adhered to the intermediate film formed on the filter-filled filter molded body to form a filtration membrane. In the present embodiment, since the clogging material configured as described above is filled in the space before reaching the water collecting slit, the filtration membrane slurry (the intermediate membrane slurry and the upper filtration membrane slurry) The water and the like contained in the water remain in the liquid pool and do not lift and separate the filtration membrane, and the filtration membrane can be formed normally over the entire area of the predetermined cell.

In addition, when forming the filtration membrane, as described above, a defect may occur in the gripping portion that grips the end face, so that the end face of the formed clogging material-filled molded product is set to 30%. Cut about mm. Next, a glaze such as glass frit is applied to the cut and newly formed end face of the filler-filled molded product, dried once, and then fired at 900 to 140 ° C. To manufacture a ceramic honeycomb filter. The conditions for applying and firing the glaze can be determined according to the conventional method of manufacturing ceramic honeycomb fillers.

The ceramic honeycomb filter thus obtained effectively prevents the fluid to be filtered and the filtered fluid from staying inside, and can supply a highly clean filtered fluid.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.

(Examples 1 to 17)

Throughout all the examples, alumina having a predetermined average particle size as an aggregate particle and glass frit as an inorganic binder were mixed at a mass ratio of 9: 1. Parts by mass, water and 4.5 parts by mass of methylcellulose as an organic binder, and 1 part by mass of a dispersant were added and kneaded to obtain a kneaded material. Is extruded with a honeycomb molding machine and then dried to form an unsintered filter having an outer diameter of 180 mm, a length of 100 mm, and an inner diameter of Φ 2.3 mm inside the inside of the filter. Obtained the form. In the present example, electrofused alumina having a raw material particle size of 0.2 to 0.5 mm and an alumina purity of 99.8% was pulverized by a dry method for a predetermined time, and the average particle sizes were 30 rn and 50, respectively. m, 100 m were designated as alumina A, alumina B, and alumina C.

Next, a water collecting slit that penetrates a predetermined cell from one part of the side surface of each green filter molded body and communicates with the other part is formed, and a green filter molded body with a water collecting slit is formed. Obtained. The shape of the catchment slit was rectangular.

Next, a clogging material is placed in each of the obtained unsintered filter molded bodies with water collecting slits in a space from each end face of a predetermined cell to a water collecting slit penetrating the predetermined cell. Filling was performed to obtain a plugged material-filled green compact. In each of the examples, a material obtained by mixing aggregate particles, an inorganic binder, a binder, a thickener, and a water retention agent in the proportions shown in Tables 1 and 2 was used as a plugging material.

Aggregate particles

Inorganic binder Binder Thickener Water retention agent Horizontal diameter (parts by mass) (parts by mass) (parts by mass) (parts by mass) (parts by mass) Material name (parts by mass)

(^ m) Example 1 Alumina A 30 95 5 0.1 0. 05 5.6 22 Example 2 Alumina A 30 90 10 0.1 0.15 5.6 22 Example 3 Alumina A 30 85 15 0. 1 0.05 5.6 22 Example 4 Alumina B 50 90 10 0.1 0.15 5.6 22 Example 5 Alumina C 100 90 10 0.1.05 5.6 22 Example 6 Alumina B 50 90 10 0.06 0.05 5.6 22 Example 7 Alumina B 50 90 10 0.08 0.05 5.6 22 Example 8 Alumina B 50 90 10 0.12 0.05 5.6 22 Example 9 Alumina B 50 90 10 0.14 14.05 5.6.22

DO aggregate particles

Inorganic binder Binder Thickener Water retention agent Water

Average particle size

'' (Parts by mass) (parts by mass) (parts by mass) (parts by mass) (parts by mass) (parts by mass)

(^ m) Example 10 Alumina B 50 90 10 0.10.02 5.6.22 Example 11 Alumina B 50 90 10 0.1.08.6.22 Example 12 Alumina B 50 90 10 0. 1 0.10 5.6 22 Example 13 Alumina B 50 90 10 0.1 0.1 0.25 5.622 Example 14 Alumina B 50 90 10 0.1.05 4.8.22 Example 15 Alumina B 50 90 10 0.10.05 5.4 22 Example 16 Alumina B 50 90 10 0.1.05 6.022 Example 17 Alumina B 50 90 10 0.1.05 6.22 22

In each of the examples, the ratio (%) of the shrinkage defect of the plugging material in the dried state of the plugging material-filled unsintered fill molding was measured. The shrinkage defect of the plugging material is a defect in the center of the plugging material filling portion when moisture is supplied to the filling portion after the portion filled with the plugging material is dried. The ratio of clogging defect of clogging material (%) is a value calculated by calculating the ratio (%) of the number of clogging defect of clogging material to the number of cells filled with clogging material. The results are shown in Tables 3 and 4.

¾) 3 Saying the day

Crack generation rate Pore diameter Porosity Bending strength

Ratio of shrinkage defects Dry workability Foaming inspection Stagnation inspection

(%) (m) (%) (kP a)

(%)

Example 10 2 〇 0.8 10.23 37 13 13 〇 Example 11 2 〇 0 10.1 36 〇 16 〇 Example 12 1 〇 0.3.2 35 〇 15 〇 Example 13 2 〇 0. 5 9.93 6 Δ17 〇 Example 14 3 〇 2. 5 9.93 6 〇 15 〇 Example 15 2 〇 1.9 10.1 36 〇 15 〇 Example 16 2 〇 2. 1 10. 2 35 〇 16 〇 Example 17 1 〇 2. 5 10. 0 36 Δ 18 〇

¾) 4 Next, the obtained plugged material-filled unfired filter molded body is fired to obtain a plugged material-filled filter molded product, and the inner peripheral surface of a predetermined cell constituting the obtained plugged material-filled filter molded product. A filter membrane was formed, dried and fired, and the end face was cut to a predetermined length. At this time, the dry processability of the fired filter material filled with plugging material was evaluated by checking whether sparks fly from the cutting blade that cuts each filter-filled plugging material. The results are shown in Tables 3 and 4. If the amount of the inorganic binder contained in the plugging material is large, the strength of the fired plugging material filled filter molded body increases and sparks may fly from the cutting blade at the time of cutting, resulting in poor machinability. The sample that could be cut well without cutting was marked as 〇, and the spark was slightly blown, but the cut was satisfactorily cut as と. Those that were no longer rated are X. The results are shown in Tables 3 and 4.

In the ceramic honeycomb fills of Examples 1 to 17, the crack occurrence rate (%) was measured at the portion filled with the plugging material. The crack occurrence rate (%) is a value calculated by calculating the ratio (%) of the number of cracked cells to the number of cells filled with clogging material. The results are shown in Tables 3 and 4.

Further, the pore diameter (m) and porosity (%) of the clogging member formed by firing the clogging material were measured. The results are shown in Tables 3 and 4.

In addition, the plugging material used to form each ceramic honeycomb filter was molded into a block shape, and a test piece having a width of 10 mm, a thickness of 5 mm, and a length of 50 mm was cut out. A three-point bending strength measurement with a distance between supports of 30 mm was performed. The results are shown in Tables 3 and 4.

Each ceramic honeycomb filter is immersed in water, the water collecting slit provided near one end face of each ceramic honeycomb filter is closed, air is sent from the other water collecting slit, and foam is generated from each ceramic 82 cam filter. The foaming test was performed by measuring the pressure at that time. The results are shown in Tables 3 and 4. In the foaming test evaluation, if no foaming is seen from the clogging member and the outer wall when pressurized at 8 kPa, it is judged as 〇, and if foaming is not seen when pressurized at 6 kPa Is indicated by △, and X is indicated when foaming is observed when pressurized at 3 kPa. The results are shown in Tables 3 and 4.

Also, the fluid to be filtered flows in from one end face of each ceramic honeycomb filter. It was measured whether filtration fluid stayed between the water collecting slit and the clogging member when the purification was performed. If there was no stay, it was marked as 〇, and if there was stay, it was marked as X. The results are shown in Tables 3 and 4.

(Comparative Examples 1 and 2)

A predetermined position in the space from each end face of a predetermined cell to a water collection slit penetrating the predetermined cell, in the green body formed with a water collection slit, and in the comparative example 1, four points from the end face 0 mm position (73% from the end surface of the specified cell in the space from the end surface of the specified cell to the water collecting slit), and 35 mm from the end surface in Comparative Example 2. Fill the filling material up to the position (up to 64% from the end surface of the specified cell in the space from the end surface of the specified cell to the water collection slit) and fill the unfilled filter with the filling material. A ceramic honeycomb filter was manufactured in the same manner as in the above-described example except that a molded body was obtained, and the same measurement was performed. Tables 5 and 6 show the composition of the clogging material and the results of each measurement.

Aggregate particles

Inorganic binder Binder Thickener Water retention agent Water Average particle size

Raw material name (parts by mass) (parts by mass) (parts by mass) (parts by mass) (parts by mass) (parts by mass)

(^ m) Comparative Example 1 Alumina B 50 90 10 0.10. 05 5.6 22 Comparative Example 2 Alumina B 50 90 10 0.1.

Five

Of clogging material

Crack generation rate Pore diameter Porosity Bending strength

() (m) (%) (kP a)

()

Comparative Example 1 5 〇 0 1 0.2 3 7 X 15 X Comparative Example 2 6 〇 0 1 0.1 3 6 X 14 X

¾6 As shown in Table 3, Table 4, and Table 6, the ceramic honeycomb filters of Examples 1 to 17 were obtained from each end face of a given cell until reaching the water collection slit penetrating the given cell. Since the space was filled with the clogging material, there was no stagnation of the filtered fluid in the above-mentioned space, and a highly clean filtered fluid could be supplied. In addition, the ceramic honeycomb fills of Examples 1 to 17 show excellent values in the percentage of shrinkage defects of the plugging material (%), dry workability, crack occurrence rate (%), and foaming inspection. In addition, the pore size (m) and the porosity (%) were suitable for use as a filter. In the ceramic honeycomb filters of Comparative Examples 1 and 2, since a liquid pool was formed between the water collecting slit and the clogging member, there was retention of the filtered fluid, which caused contamination of the filtered fluid. there were. In addition, in the foaming test, foaming is observed when both are pressurized at 3 kPa, and when used as a filter, the fluid to be filtered passes through the gap where the foaming occurred and is filtered by the filtration membrane. Therefore, they could flow into the filtration fluid without being used, and could not be used as filters. Industrial applicability

As described above, the ceramic honeycomb filter of the present invention can effectively prevent the fluid to be filtered and the filtered fluid from staying inside, and can supply a highly purified filtered fluid. In a wide range of fields such as water treatment, exhaust gas treatment, and pharmaceutical and food fields, it can be suitably used for removing suspended substances, bacteria, dust and the like in liquids and gases.

Claims

The scope of the claims

1. A plurality of membrane filtration cells which are partitioned by a porous partition wall made of ceramics and in which a filtration membrane is disposed, and serve as flow paths for a fluid to be filtered, and are partitioned by the partition walls and sandwich the partition walls. A plurality of water collecting cells adjacent to the predetermined membrane filtration cell and serving as a flow path of the filtered fluid in which the fluid to be filtered is filtered by the filtration membrane; and an outer wall surrounding the membrane filtration cell and the water collection cell A part of the outer wall at a predetermined distance from both ends of the water collecting cell on the outer wall for flowing out the filtered fluid that has passed through the water collecting cell, A water collecting slit penetrating from the water collecting cell to the other part of the outer wall, and a pore filled in a space from each end face of the water collecting cell to the water collecting slit. Quality clogging material and Ceramic honeycomb filter provided with.

2. The ceramic honeycomb filter according to claim 1, wherein the clogging member is formed of a porous body having a plurality of communication holes.

3. The ceramic honeycomb filter according to claim 1, wherein the clogging member is formed of a porous material including at least one material selected from the group consisting of alumina, mullite, selven, and cordierite. .

4. The ceramic honeycomb film according to claim 2, wherein each of the plurality of communication holes formed in the clogging member has a portion having a hole diameter of 20 nm or less.

5. The ceramic honeycomb filter according to any one of claims 2 to 4, wherein the porosity of the clogging member is 25 to 50%.

6. The ceramic honeycomb filter according to any one of claims 1 to 5, wherein a thermal expansion coefficient of the clogging member is lower than or equal to a thermal expansion coefficient of the partition wall.

7. Each of the plurality of membrane filtration cells having a cross section perpendicular to the flow direction of the fluid to be filtered is a circle, an ellipse, an oval, a triangle, a square, a pentagon, a hexagon, and a heptagon. The ceramic honeycomb filter according to any one of claims 1 to 6, wherein the ceramic honeycomb filter has at least one shape selected from a group.

8. Each of the cross sections of the plurality of water collection cells perpendicular to the flow direction of the filtration fluid is selected from the group consisting of a circle, an ellipse, an oval, a triangle, a square, a pentagon, a hexagon, and a heptagon. 8.A method according to claim 1, wherein the shape is at least one shape. The ceramic honeycomb fill evening described.

9. Extruding the raw material to obtain a green filter molded body having a predetermined shape having cells serving as flow paths for the fluid to be filtered and the filtered fluid,

The obtained unsintered filter molded body is provided with a water collecting slit penetrating from one part of the side surface of the obtained unsintered filter molded body and passing through the predetermined cell to another part to form an unsintered filter molded body with a water collecting slit. Get

The obtained unsintered filter molded body with the water collecting slit is filled with a plugging material in a space from each end face of the predetermined cell to the water collecting slit penetrating the predetermined cell. Filling to obtain a plugged material-filled unfired filter molded body,

The obtained plugged material-filled unfilled molded product is fired to obtain a plugged material-filled molded product,

A method for manufacturing a ceramic honeycomb filter, wherein a filtration membrane is formed on the inner peripheral surface of a predetermined cell constituting the obtained plugging material-filled molded article and fired.

10. The method for manufacturing a ceramic honeycomb filter according to claim 9, wherein the plugging material includes an aggregate particle, an inorganic binder, a binder, a thickener, and a water retention agent.

11. The ceramic according to claim 10, wherein the binder constituting the clogging material contains 0.08 to 0.12 parts by mass with respect to 100 parts by mass of the aggregate particles. 11. Manufacturing method of honeycomb filter.

12. The thickener according to claim 10, wherein the thickener constituting the plugging material is contained in an amount of 0.04 to 0.1 part by mass based on 100 parts by mass of the aggregate particles. 11. Manufacturing method of ceramic honeycomb filter.

13. The ceramic carrier according to any one of claims 10 to 12, wherein the water retention agent constituting the plugging material is contained in an amount of 5 to 6 parts by mass based on 100 parts by mass of the aggregate particles. How to make two cam fill.

14. The ceramic honeycomb force filter according to any one of claims 9 to 13, wherein both end faces are cut to a predetermined length after the filtration membrane is formed on the plugging material-filled molded body. Production method.

15 5. The aggregate particles constituting the plugging material are alumina, mullite, selven The method for producing a ceramic honeycomb filter according to any one of claims 10 to 14, which is at least one compound selected from the group consisting of, and cordierite.

16. The inorganic binder constituting the plugging material is at least one compound selected from the group consisting of alumina, silica, zirconium, glass frit, feldspar, and cordierite. 6. The method for manufacturing a ceramic honeycomb filter according to any one of 5.

17. The binder according to any one of claims 10 to 16, wherein the binder constituting the plugging material is at least one compound selected from the group consisting of polyvinyl alcohol, polyethylene glycol, starch, and clay. Ceramic honeycomb filter