WO2004026439A1

WO2004026439A1 - Fluid filter

Info

Publication number: WO2004026439A1
Application number: PCT/JP2003/011800
Authority: WO
Inventors: Tomohiro Yamamoto; Eigo Tanuma; Satoshi Sumiya
Original assignee: Bridgestone Corporation; Johnson Matthey Japan Incorporated
Priority date: 2002-09-19
Filing date: 2003-09-17
Publication date: 2004-04-01
Also published as: JPWO2004026439A1; AU2003266520A1

Abstract

A fluid filter (1) is a rectangular parallelepiped-shaped board-like body constructed from an air-permeable ceramic porous body with a three-dimensional mesh-like skeleton structure. The board-like body has a large number of empty chambers (2) that are through-holes penetrating from one side-face (1a) to the other side-face (1b) parallel to the one side face. The through-holes are round holes and are arranged so as to be in a stagger form at the side faces (1a, 1b). Providing the empty chambers (2) reduces pressure loss and enables the fluid filter to remove dust from a gas for a long period at reduced pressure loss.

Description

Description Fluid filter Field of the invention

The present invention relates to a fluid filter, and more particularly to a fluid filter made of a porous ceramic body. Background of the Invention

Conventionally, a synthetic resin foam having a three-dimensional network skeleton structure with internal communication space, for example, a flexible polyurethane foam without a cell membrane, is immersed in a ceramic slurry, and the ceramic is adhered to the polyurethane foam skeleton and dried. A ceramic porous body having a three-dimensional network skeleton obtained by firing is known (for example, Japanese Patent Application Laid-Open No. H11-285857, Japanese Patent Laid-Open No. 2000-10973). No. 6).

This ceramic porous body has features such as low power density, high heat resistance, and low airflow resistance, that is, low pressure loss. Therefore, grease filters for kitchens, catalyst carriers, air-permeable insulation materials, and molten metal filtration materials However, it is required that the pressure loss be as low as possible for use in these applications.

Conventionally, to reduce pressure loss, the degree of adhesion of the ceramic slurry to the polyurethane foam was reduced to almost eliminate clogging. However, in this case, the apparent specific gravity was reduced and the strength was reduced. There was a problem in terms.

In addition, a method has been adopted in which various organic surfactants and peptizers are added to the ceramic slurry to adjust the slurry properties. According to this method, the skeleton becomes thicker and the strength is increased. However, there is a problem that clogging occurs slightly and the pressure loss does not decrease sufficiently. In addition, the ceramic porous body obtained has a large number of pores and a porous structure due to the large amount of combustible organic components in addition to the ceramic raw material soil. Therefore, for example, when used as a filter for dust-containing gas, dust enters the skeleton of the porous ceramic body, and the pressure loss increases with time. In addition, there is a problem in strength due to the porous skeleton. Purpose of the invention

An object of the present invention is to provide a fluid filter made of a porous ceramic body having excellent dust removal performance and low pressure loss. Summary of the Invention

The fluid filter of the first aspect has a first surface and a second surface facing the first surface, and fluid flows from the first surface to the second surface. A fluid filter comprising a porous ceramic body, wherein an empty space is provided between the first surface and the second surface. By providing this empty chamber, the pressure loss rise of the fluid filter is reduced.

In one aspect of the fluid filter of the first aspect, the porous body has a first side surface connecting the first surface and the second surface, and a second side surface facing the first side surface. The cavity is formed by a hole penetrating from the first side surface to the second side surface. In this case, it is preferable to provide a plurality of holes. Further, when the vacant space is formed by such holes, it is preferable to provide a seal layer on at least a part of the inner peripheral surface of the hole, particularly on the inner peripheral surface on the second surface side. This seal layer can be easily formed by applying a paint.

In another aspect of the first aspect, the vacant space extends along the first surface and the second surface in a direction in which these surfaces spread (two orthogonal directions).

In still another mode of the first aspect, the hole diameter on the second surface side is smaller than that on the first surface side.

The fluid filter of the second aspect is a fluid filter made of a cylindrical ceramic porous body having an outer peripheral surface and an inner peripheral surface, in which a fluid flows from one peripheral surface to the other peripheral surface. It is characterized in that there is a distribution in the average pore diameter in the flow direction of the fluid. As described above, by giving the distribution of the average pore diameter in the flow direction of the fluid, the dust removing performance is improved, and the rise in pressure loss of the fluid filter is reduced.

In this fluid filter, the dust removal performance is improved by making the average pore diameter smaller toward the downstream side in the flow direction of the fluid.

In the fluid filter of the second aspect, the area where the average pore diameter is the same is the area of the fluid filter. It is preferable that the ring has a ring shape in the cross section in the direction perpendicular to the cylinder axis direction, and it is particularly preferable that at least two ring regions having different average pore diameters exist.

The fluid filter of the second aspect is preferably cylindrical.

The first and second aspects of the ceramic porous body are prepared by immersing a synthetic resin foam having a three-dimensional net-like skeleton structure having an internal communication space in a ceramic slurry, allowing the ceramic to adhere to the synthetic resin foam, and then drying and drying. It is preferably a ceramic porous body having a three-dimensional network skeleton structure obtained by firing.

The first and second aspect fluid filters are suitable for removing dust such as air. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1a is a perspective view of a fluid filter according to an embodiment of the first aspect, FIG. Lb is a cross-sectional view taken along line BB of FIG. 1a, and FIG. It is sectional drawing.

FIG. 2A is a perspective view of a fluid filter according to another embodiment of the first aspect, and FIG. 2B is a cross-sectional view of a part of the fluid filter.

FIG. 3A is a perspective view of a fluid filter according to a different embodiment of the first spectrum, and FIGS. 3B and 3C are cross-sectional views taken along lines BB and C-C of FIG. 3A, respectively. .

FIG. 4A is a perspective view of a fluid filter according to still another embodiment of the first aspect, and FIG. 4B is a sectional view taken along line BB of FIG. 4A.

FIG. 5 is a perspective view of a fluid filter according to a comparative example.

FIG. 6 is an end view of a fluid filter according to still another embodiment of the first aspect.

FIG. 7 is an end view of a fluid filter according to still another embodiment of the first aspect.

FIG. 8 is a cross-sectional view of the fluid filter according to the second embodiment of the present invention.

FIG. 9A is a perspective view of a fluid filter according to another embodiment of the second aspect, and FIG. 9B is a cross-sectional view of the filter. Detailed description

The first and second aspects of the ceramic porous body are preferably made of a synthetic resin foam having a three-dimensional network skeleton structure having an internal communication space as a base material.

As such a synthetic resin foam, any one having a three-dimensional network skeleton structure having an internal communication space can be used, but a flexible polyurethane foam, particularly a flexible polyurethane foam having no cell membrane, can be suitably used. As the polyurethane foam without a cell membrane, a foam in which the cell membrane is eliminated by controlling foaming, or a foam in which the cell membrane is removed by an alkali treatment, heat treatment, water pressure treatment, or the like can be used. The rate and other physical properties can be selected according to the application.

In the first aspect, the synthetic resin foam has a portion corresponding to the vacant room.

The ceramic porous body is obtained by immersing the above-described synthetic resin foam in a ceramic slurry, attaching a ceramic slurry to the synthetic resin foam, drying and firing, and thermally decomposing or burning the synthetic resin foam. can get.

Examples of the ceramic include oxide ceramics such as alumina, silica and cordierite, non-oxide ceramics such as silicon carbide and silicon nitride, and sialon.

Clay can be added to increase the stability of ceramic slurry. As this clay, for example, Kibushi clay and Frog-eye clay can be used. Further, it is preferable that the mixing amount be 15% or less based on all the ceramic components. If it is more than 15%, the thixotropy index changes and causes clogging.

In addition, the thixotropic property can be adjusted by adding a binder such as polybutyl alcohol and carboxymethyl cellulose to the ceramic slurry as necessary.

The viscosity of the ceramic slurry can be adjusted by adjusting the amount of water to be added according to the size of the target cell of the ceramic porous body.

Next, a synthetic resin foam having a three-dimensional network skeleton structure is immersed in the above-mentioned ceramic slurry, then excess slurry is removed, dried, and heated in a firing furnace at a temperature of about 100 to 150 ° C. By firing at a temperature, there is an internal communication space with a cell structure corresponding to the synthetic resin foam. A ceramic porous body having a three-dimensional network skeleton structure can be obtained.

[1] Explanation of the first aspect fluid filter

Hereinafter, an embodiment of the first aspect will be described with reference to FIGS. FIG. 1A is a perspective view of a fluid filter 1 according to an embodiment of the first aspect, and FIG. 1B is a cross-sectional view taken along line BB of FIG. 1A.

The fluid filter 1 is a rectangular parallelepiped plate made of the above-described ceramic porous body, and gas such as air flows from the upper surface (one main plate surface) to the lower surface (the other main plate surface) in the figure. . -A large number of cavities 2 are provided from one side 1a of the plate to the other side 1b parallel thereto. In this embodiment, the through-hole is a circular hole, but may be another shape such as an ellipse. In this embodiment, the cavities are provided in three stages in the thickness direction of the plate-like body, and the vacancies 2 are provided in a staggered arrangement on the side surface 1a. The opening area ratio of the vacant space 2 on the side surface 1a is preferably about 20 to 50%. The opening area ratio is a percentage obtained by dividing the total opening area of the vacant space 2 by the area of the side surface 1a (thickness X side length).

The fluid filter 1 provided with the vacant chamber 2 is disposed in the casing so as not to inhale gas from the side surfaces 1a and 1b and the remaining side surfaces lc and 1d, and sucks the lower side in the figure. Alternatively, the gas is circulated from the upper surface to the lower surface by pressurizing the upper surface. By providing the empty space 2, the pressure loss is reduced, and the gas can be removed with a low pressure loss over a long period of time.

As shown in Fig. 1c, lids 1t may be attached to the side surfaces 1a and lb, respectively, so that gas is not sucked from the side surfaces la and lb. This lid is preferably made of a ceramic having a low coefficient of thermal expansion.

FIG. 2A is a perspective view of a fluid filter 1A according to another embodiment of the first aspect, and FIG. 2B is a cross-sectional view of a part of the fluid filter 1A.

In the fluid filter 1A, a seal layer 3 made of a coating film is formed on the lower half side of the figure on the inner peripheral surface of the cavity 2 formed with a through hole. The seal layer 3 is preferably an organic adhesive that is usually used, or one formed by crushing with a slurry of the same quality as the ceramic foam to be obtained. This fluid filter 1 A The other configuration is the same as that of the fluid filter 1. The extending range of the seal layer 3 is 180 ° in the circumferential direction in FIG. 2, but may be between 60 ° and 180 °.

Although not shown, a lid may be attached to the side surface facing the vacant room 2 as in FIG. 1c. FIG. 3A is a perspective view of a fluid filter 4 according to a different embodiment of the first aspect, and FIGS. 3B and 3C are cross-sectional views taken along lines BB and C-C of FIG. 3A, respectively. is there.

The fluid filter 4 is formed of a rectangular parallelepiped plate made of a porous ceramic body. Gas flows from one main plate surface (upper surface in the figure) of the plate-shaped body to the other main plate surface (lower surface in the diagram). From one side surface 4a of the plate-shaped body to the other side surface 4b, there is provided an empty room 5 formed of one through hole. The empty room 5 has a rectangular cross-sectional shape and extends in a direction parallel to the main plate surface. The ratio of the opening area on the side surface 4a of the empty space 5 is preferably about 50 to 90%. It is preferable that the left-right width of FIG.

The fluid filter 4 having the empty space 5 is also arranged in the casing so as not to draw gas from the side surfaces 4a, 4b, 4c, and 4d. Pressurization allows gas to flow from the upper main plate surface to the lower main plate surface. Since the fluid filter 4 also has the empty space 5, the pressure loss is kept low for a long time. Although not shown, a sealing layer may be provided on the lower surface of the vacant room 5 in the figure. .

Although illustration is omitted, lids may be attached to the side surfaces 4a and 4b as in Fig. 1c. FIG. 4A is a perspective view of a fluid filter 1B according to still another embodiment of the first aspect, and FIG. 4B is a sectional view taken along line BB of FIG. 4A.

The fluid filter 1B is obtained by integrally providing a plate-shaped body 8 made of a porous ceramic body on one main plate surface of the fluid filter 1A shown in FIG. The hole diameter of the plate member 8 is also smaller than the hole diameter of the fluid filter 1A. The thickness of the plate 8 is preferably about 15 to 20% of the thickness of the fluid filter 1A.

In order to manufacture the fluid filter 1B, a synthetic resin foam for manufacturing the fluid filter 1A and a synthetic resin foam for manufacturing the plate-shaped body 8 are laminated and integrated, and this is immersed in a ceramic slurry. Others may be the same as above.

This fluid filter 1B is also housed inside the casing so that gas is not sucked from the four sides. In this case, the lower surface side (plate-like body 8 side) in the figure is sucked or the upper surface side is pressurized, and gas flows from the upper surface side to the lower surface side.

Although not shown, lids may be attached to the side surfaces 1a and 1b as in Fig. 1c. 6 and 7 show fluid filters 9 and 9 according to still another embodiment of the first aspect.

It is an end elevation of A.

The fluid filter 9 in FIG. 6 is a cylindrical shape having a center hole 10, and has a plurality of cavities 11, 12, 13 formed of through holes penetrating in a direction parallel to the axis of the cylinder. The cavities 11 are arranged concentrically on the outermost side, the cavities 13 are arranged concentrically on the innermost side, and the cavities 12 are arranged concentrically between them. Have been. The arrangement of the vacancies 1, 12, and 13 is staggered at the end face of the fluid filter 9. Vacancies 11, 12, and 13 have smaller diameters in this order. The total open area ratio of the vacancies 11, 12> 13 is preferably about 20 to 50% at the end face of the fluid filter 9.

The fluid filter 9 is disposed in the casing so as not to inhale gas from both end surfaces, and sucks the inside of the center hole 10 or pressurizes the outer peripheral side to flow the gas from the outer peripheral surface toward the inner peripheral surface. Let it.

Although illustration is omitted, lids may be attached to both end surfaces of the filter, as in FIG. 9 described later. This lid has an annular shape similar to a lid 30t in FIG. 9 described later, and the center hole 10 is not closed.

Since the fluid filter 9 also has the vacancies 11, 12, and 13, the pressure loss is kept low for a long period of time.

Also in this cylindrical fluid filter, the seal layer 14 may be provided on the suction side of the inner peripheral surface of the empty space like the fluid filter 9A in FIG. In FIG. 7, the seal layer 14 extends 180 ° in the circumferential direction, but may be about 60 to 180 °.

Such a fluid filter of the first aspect has a pore number of 6 to 25/25 mm and a porosity of 75 to 95%, particularly 75 to 90%, as a filter for dust-containing gas. Preferably, there is. The fine filter material constituting the second plate-shaped body 8 in FIG. 4 described above has a porosity of 30 to 45 holes / 25 mm and a porosity of 75 to 95%, particularly 78 to 92%. %. The measurement results of the pressure loss of the fluid filters 1, 1A, 4, 1B shown in FIGS. 1 to 4 and the fluid filter 20 according to the comparative example shown in FIG. 5 will be described below.

The ceramic porous body (except for the plate-like body 8 in FIG. 4) in each of the examples was manufactured as follows.

That is, a ceramic slurry was prepared by mixing 95 parts by weight of Bayer method alumina, 5 parts by weight of Kibushi clay, 4 parts by weight of polyvinyl alcohol, and 20 parts by weight of water. A flexible polyurethane foam having a three-dimensional network structure without a cell membrane and having a shape of 60 cm × 24 cm × 24 cm having 30 cells per inch (25 mm) was immersed in the slurry. Excess slurry was removed, dried sufficiently, and then baked at 1300 ° C for 10 minutes to obtain a porous ceramic body. The average pore size of this porous ceramic body is 0.83 mm.

The plate-shaped body 8 in Fig. 4 is manufactured using a flexible polyurethane foam with a cell membrane without a cell membrane having a shape of 1 cm x 24 cm x 24 cm with 40 cells per inch (25 mm). did. The average pore size of the porous ceramic body is 0.6 mm.

The configurations of the fluid filters of the respective examples and comparative examples are as follows.

Example 1: As shown in Fig. 1, a 7 cm x 24 cm x 24 cm plate-like body has a diameter of 1.

There were 32 vacancies 2 with 5 cm holes. The open area ratio of vacancies is 33.6%.

Example 2: In Example 1, as shown in Fig. 2, a ceramic slurry was applied to the lower semicircular surface on the lower side of the cavity 2 having holes to provide a 0.2 mm thick sealing layer.

Example 3: In Example 1, instead of the vacant space composed of holes, a vacant room 5 of l cm x 22 cm x 22 cm is provided at the center in the thickness direction as shown in FIG. Example 4: As shown in Fig. 4, a fluid filter 1A made of a 6-cm-thick ceramic porous body and a plate-shaped 1-cm-thick ceramic porous body with a porosity of 85% and an average pore diameter of 0.6 mm The one with body 8 integrated.

Comparative Example 1: As shown in FIG. 5, the same ceramic porous body as in Example 1 having a thickness of 7 cm was used. Dust-containing air was passed through each fluid filter at a wind speed of 1 m / sec or 3 m / sec, and the pressure loss and the change over time in the collection rate were measured. As the dust-containing air, air containing JIS-15 type dust was used. Dust content is the case when the wind speed 1 m / sec 0. 1 6 gm wind speed 3m / sec 0. 05 g / m 3. The results are shown in Table 1 below.

As shown in Table 1, Examples 1 to 4 have lower pressure loss and higher dust collection rate than Comparative Example 1. [2] Explanation of fluid filter of 2nd aspect

In the fluid filter of the second aspect, fluid flows from one peripheral surface to the other peripheral surface. You. In this flow direction, the average pore size has a distribution, and preferably, the average pore size on the downstream side in the flow direction is reduced.

In order to give the distribution of the average pore diameter in this way, the above-described method for producing a ceramic porous body having a three-dimensional network skeleton structure involves synthesizing a three-dimensional network skeleton structure having different average pore diameters, that is, different roughnesses. A tubular body in which a resin foam tubular body is coaxially engaged is manufactured, and this tubular body is immersed in ceramic slurry to remove excess slurry, dried, and fired in a firing furnace.

When dust is removed from the air by the fluid filter of the second aspect, it is preferable that the air be circulated from the outer peripheral surface side to the inner peripheral surface side. In this case, the average pore diameter becomes smaller toward the inner peripheral surface side It is preferable to do so. On the outermost peripheral side of the fluid filter, it is preferable that the number of pores is 6 to 25 and Z25 mm, and the porosity is 75 to 95%. Further, on the innermost peripheral side, it is preferable that the number of vacancies is 30 to 50/25 111111 and the porosity is 75 to 95%.

However, the air may be circulated from the inner peripheral surface side to the outer peripheral surface side. In this case, it is preferable that the average pore diameter becomes smaller toward the outer peripheral surface side.

Hereinafter, an embodiment of the second aspect will be described with reference to FIG. FIG. 8 is a cross-sectional view of the fluid filter 30 according to the embodiment of the second aspect in a direction orthogonal to the cylinder axis direction.

The fluid filter 30 has a cylindrical shape. A gas such as air flows as a fluid from the outer peripheral surface 41 to the inner peripheral surface 42 or from the peripheral surface 42 to the outer peripheral surface 41. The fluid filter 30 has three regions, a relatively coarse first region 31, a relatively fine third region 33, and a second region 32 where the coarseness is intermediate between them. Yes. When the fluid flows from the outer peripheral surface toward the inner peripheral surface, the first region 31 is arranged at the outermost periphery, the third region 33 is arranged at the innermost periphery, and the second region 32 is arranged between them. It has been.

Conversely, when the fluid flows from the inner peripheral surface 42 to the outer peripheral surface 41, the first region is disposed on the innermost periphery, and the third region is disposed on the outermost periphery.

The first region 31 has a pore number of 6 to 25/25 mm, particularly 13 to 22/25 mm, and a porosity of 75 to 95%, particularly 75 to 90%. In particular, it is preferably 85-90%. Good.

The second region 32 has a porosity of 20 to 35 holes / 25 mm, particularly 27 to 35 holes / 25 mm, and a porosity of 75 to 95%, particularly 84 to 8.8%. It is preferable that

The third region 33 has a porosity of 30 to 50 25 mm, particularly 35 to 45/25 mm, and a porosity of 75 to 95%, particularly 78 to 92%. It is preferably from 82 to 86%.

The radial thickness of the first region is preferably 38 to 46% of the total of the first, second, and third regions, and the radial thickness of the second region is the first, second, and third regions. The total thickness of the third region is preferably 38 to 46%, and the radial thickness of the third region is preferably 11 to 22% of the total of the first, second, and third regions.

Although three regions 31, 32, and 33 are provided in FIG. 8, two regions may be provided, or four or more regions may be provided. However, in consideration of the production cost and the dust removal characteristics, about 3 to 4 regions are preferable.

When used as an air filter, the outer diameter (diameter) of the fluid filter 30 is preferably about 200 to 30 Omm, and the inner diameter (diameter) is preferably about 90 to 12 Omm. The length of the fluid filter 30 in the cylinder axis direction is preferably about 0.5 to 1.5 times the outer diameter. The air circulation speed is preferably about 2 to 7 mZ sec.

As shown in FIG. 9, lids 30t may be attached to both end faces of the filter 30. This lid 30t is annular. This lid is preferably made of ceramic with a low coefficient of thermal expansion.

When a fluid such as air flows from the inner peripheral surface side to the outer peripheral surface side, as described above, the first region 31 is disposed on the innermost peripheral side, and the third region is disposed on the outermost peripheral side. Just fine. Also in this case, two or four or more regions may be provided, and from the viewpoint of cost and the like, approximately three to four regions are preferable.

Next, the results of pressure loss measurement performed on the fluid filter 30 shown in FIG. 8 and the fluid filter according to the comparative example will be described.

The ceramic porous body of Example 5 was manufactured as follows.

That is, 95 parts by weight of alumina by the Bayer method, 5 parts by weight of Kibushi clay, 4 parts by weight of polyvinyl alcohol, and 20 parts by weight of water were mixed to prepare a ceramic slurry. In addition, a 3D reticulated framework without a cell membrane, which has a cylindrical shape with an outer diameter of 24.4 cm, an inner diameter of 19.3 cm, and a length of 10.2 cm, with 24 cells per inch (25 mm). Flexible polyurethane foam (for the 1st zone) and a cylindrical shape with 30 cells per inch (25 mm), 19.3 cm outside diameter, 14.2 cm inside diameter, and 10.2 cm length 3D reticulated skeleton flexible polyurethane foam (for the 2nd area) without cell membrane and 40 cells per inch (25mm) outside diameter 14.2 cm, inside diameter 12.2 cm, long A polyurethane foam cylindrical body was manufactured by fitting a flexible polyurethane foam (for the third region) having a cylindrical shape of 10.2 cm without a cell membrane and having a three-dimensional network skeleton structure. This tubular body was immersed in the slurry. Remove excess slurry, dry thoroughly, then 1300. C was fired for 10 hours to obtain a ceramic porous body. The average pore diameter of the ceramic porous body is 1.04 mm in the first region, 0.82 mm in the second region, and 0.6 lmm in the third region. After firing, the outer diameter of the fluid filter is 24 Omm, the inner diameter is 120 mm, the length is 100 mm, the thickness of the first area is 25 mm, the thickness of the second area is 25 mm, and the third area Is 10 mm thick.

The fluid filter of Comparative Example 2 is entirely a ceramic porous body in the first region described above, the fluid filter of Comparative Example 3 is entirely a ceramic porous body of the second region, and the fluid filter of Comparative Example 4 is entirely Is the ceramic porous body in the third region.

Dust-containing air was passed through each fluid filter at a wind speed of 3 m / sec to measure the pressure loss and the change over time in the collection rate. As the dust-containing air, air containing 0.08 g / m ^{3 of} JIS-12 dust was used. The results are shown in Table 2 below.

Table 2

As shown in Table 2, Example 5 has a low pressure loss and a high dust collection rate overall

Claims

The scope of the claims

1. A fluid filter comprising a ceramic porous body having a first surface and a second surface opposed to the first surface, wherein a fluid flows from the first surface to the second surface. A fluid filter, wherein an empty room is provided between a first surface and a second surface.

2. The fluid filter according to claim 1, wherein a plurality of the holes are provided as the empty chamber.

3. The fluid filter according to claim 2, wherein a fluid seal layer is provided on at least a part of the inner peripheral surface of the hole.

4. The fluid filter according to claim 3, wherein the fluid seal layer is provided on the second surface side of the inner peripheral surface of the hole.

5. The fluid finletter according to claim 3, wherein the fluid seal layer is formed of a coating film.

6. The fluid filter according to claim 1, wherein the empty space extends along the first surface and the second surface.

7. The fluid filter according to claim 1, wherein the pore diameter on the second surface side is smaller than that on the first surface side.

8. The fluid filter according to claim 1, wherein the number of pores in the porous ceramic body is 6 to 25/25 mm, and the porosity is 75 to 95%.

9. In claim 1, the porous ceramic body is a plate-like body, and a fluid flows from one main plate surface to the other main plate surface, and from one side surface of the plate-like body to another side surface parallel to the main body surface. A fluid filter, wherein a large number of vacant chambers each having a through hole are provided.

10. The fluid filter according to claim 9, wherein the empty chambers are provided in a plurality of stages in the thickness direction of the plate-shaped body, and the empty chambers are provided in a staggered arrangement on the side surface.

11. The fluid filter according to claim 9, wherein an open area ratio of the vacant space on the side surface is 20 to 50%.

12. In claim 9, the other of the inner peripheral surfaces of the vacant chambers formed by the through holes. A fluid filter, wherein a fluid seal layer is formed on a main plate surface side.

13. In claim 9, a second plate-like body made of a ceramic porous body having a smaller hole diameter than the ceramic porous body is laminated on the other main plate surface of the first plate-like body made of the ceramic porous body. A fluid filter characterized by being performed.

14. The fluid filter according to claim 13, wherein the thickness of the second plate is 15 to 20% of the thickness of the first plate.

15. The method according to claim 13, wherein the number of porosity of the ceramic porous body constituting the second plate-like body is 30 to 45/25 mm, and the porosity is 75 to 95%. A fluid filter characterized by the following.

16. The ceramic porous body according to claim 1, wherein the ceramic porous body is a plate-like body, and fluid flows from one main plate surface to the other main plate surface, and the fluid flows from one side surface of the plate-like body to the other main plate surface. A fluid filter, characterized in that a void formed by a single through-hole having a rectangular cross section is provided on the side surface.

17. In claim 16, the opening area ratio of the vacant space on the side surface is 50 to 90%, and the width of the vacant space on the side surface is 70 to 90% of the width of the plate-like body. Fluid filter characterized by%.

18. The ceramic porous body according to claim 1, wherein the porous ceramic body has a cylindrical shape having a center hole, and has a plurality of cavities formed through holes parallel to an axis of the cylinder. Fluid filter.

19. The fluid filter according to claim 18, wherein the fluid filter circulates a fluid from an outer peripheral surface to an inner peripheral surface of the cylindrical porous ceramic body, the fluid filter having a plurality of types of vacancies having different hole diameters, A fluid filter, wherein the chamber is arranged so that the hole diameter of the chamber increases from the inner peripheral side to the outer peripheral side of the cylinder.

20. The fluid filter according to claim 18, wherein the fluid filter allows fluid to flow from the inner peripheral surface to the outer peripheral surface of the cylindrical ceramic porous body, and has a plurality of types of vacancies having different hole diameters. A fluid filter, wherein the chamber is arranged so that the hole diameter of the chamber increases from the outer peripheral side to the inner peripheral side of the cylinder.

21. The synthetic resin foam according to claim 1, wherein the ceramic porous body is formed by immersing a synthetic resin foam having a three-dimensional network skeleton structure having an internal communication space into a ceramic slurry. A fluid filter characterized by being a porous ceramic having a three-dimensional network skeleton structure obtained by attaching a ceramic to a ceramic, drying, and firing.

22. The fluid filter according to any one of claims 1 to 21, wherein a lid is provided on a side surface intersecting the first surface and the second surface.

23. The fluid filter according to claim 22, wherein the lid is made of a material having a low coefficient of thermal expansion.

24. The fluid finoleter according to claim 23, wherein the material is ceramic.

25. In a fluid filter comprising a cylindrical ceramic porous body having an outer peripheral surface and an inner peripheral surface, in which a fluid flows from one peripheral surface to the other peripheral surface,

A fluid filter, characterized in that there is a distribution of average pore diameters in the flow direction of the fluid.

26. The fluid filter according to claim 25, wherein the average pore diameter is smaller toward the downstream side in the flow direction of the fluid.

27. The fluid filter according to claim 26, wherein the fluid flows from the outer peripheral surface toward the inner peripheral surface.

28. The fluid filter according to claim 27, wherein the regions having the same average pore diameter are annularly formed in a cross section of the fluid filter in a direction orthogonal to the cylinder axis direction.

29. The fluid filter according to claim 27, wherein there are at least two annular regions having different average pores.

30. The fluid filter according to claim 25, wherein the fluid filter is cylindrical.

31. The fluid filter according to claim 30, wherein the fluid is circulated from the outer peripheral surface side to the inner peripheral surface side, and the average pore diameter is smaller toward the inner peripheral surface side.

3 2. In claim 31, on the outermost peripheral side, the number of holes is 6 to 25/25 mm, the porosity is 75 to 95%, and the innermost peripheral side is Te, an empty hole number 3 ^{0-4 five} Roh

A fluid filter characterized by having a porosity of 25 to 95% and a porosity of 25 to 95%.

33. In Claim 28, the fluid is circulated from the outer peripheral surface side to the inner peripheral surface side in a cylindrical shape, and the first region having a large average pore diameter, the third region having a small average pore diameter, and the average pore diameter are defined as these. The first region is located on the outermost periphery and the third region The fluid filter is characterized in that the region is disposed on the innermost periphery and the second region is disposed between them.

34. The method according to claim 28, wherein the fluid is circulated from the inner peripheral surface side to the outer peripheral surface side, and the first region having a large average pore diameter, the third region having a small average pore diameter, and the average pore diameter are defined as these. It has three regions, a second region and a middle region, wherein the first region is arranged on the innermost periphery, the third region is arranged on the outermost periphery, and the second region is arranged between them. Features Fluid filter.

35. In Claim 33, the first region has 6 to 25 holes / 25 mm, the porosity is 75 to 95%, and the second region has 20 to 50 holes. 35/25 mm, porosity is 75 to 95%, and the third region has 30 to 50 porosity Z 25 mm, porosity is 75 to 95% A fluid filter, characterized in that:

36. In claim 34, the first region has 6 to 25 holes / 25 mm, the porosity is 75 to 95%, and the second region has 20 to 50 holes. 35/25 mm, porosity is 75 to 95%, and the third region has 30 to 50 porosity Z 25 mm, porosity is 75 to 95% A fluid filter, characterized in that:

37. In claim 33, the radial thickness of the first region is 38 to 46% of the total of the first, second, and third regions, and the radial thickness of the second region. Is 38 to 46% of the total of the first, second and third regions, and the radial thickness of the third region is 11 to 2 of the total of the first, second and third regions. A fluid filter characterized by 2%.

38. In Claim 34, the radial thickness of the first region is 38 to 46% of the total of the first, second, and third regions, and the radial thickness of the second region. Is 38 to 46% of the total of the first, second and third regions, and the radial thickness of the third region is 11 to 2 of the total of the first, second and third regions. A fluid filter characterized by 2%.

39. In Claim 33, the outer diameter is 200 to 300 mm, the inner diameter is 90 to: L20 mm, and the length in the cylinder axis direction is 0.5 to 1 of the outer diameter. . Fluid characterized by a factor of 5

40. In claim 34, the outer diameter is 200 to 300 mm, the inner diameter is 90 to: I 20 mm, and the length in the cylinder axis direction is 0.5 to 1 of the outer diameter. . Fluid characterized by a factor of 5

41. The ceramic porous body according to claim 25, wherein the ceramic porous body has a three-dimensional network skeleton structure synthetic resin foam having an internal communication space immersed in a ceramic slurry to adhere the ceramic to the synthetic resin foam. A fluid filter characterized by being a porous ceramic having a three-dimensional network skeleton structure obtained by drying and firing.

42. The fluid filter according to any one of claims 25 to 41, wherein a lid is provided on an end face of the fluid filter.

43. The fluid finoleter according to claim 42, wherein the lid is made of a material having a low coefficient of thermal expansion.

44. The fluid filter according to claim 43, wherein the material is ceramic.