JP4110982B2 - Fluid filter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fluid filter, and more particularly to a fluid filter made of a ceramic porous body.
[0002]
[Prior art]
Conventionally, a synthetic resin foam having a three-dimensional network skeleton structure having an internal communication space, for example, a soft polyurethane foam without a cell membrane is immersed in a ceramic slurry, and the ceramic is attached to the skeleton of the polyurethane foam, which is dried and fired. Ceramic porous bodies having a three-dimensional network skeleton obtained by this method are known (for example, JP-A Nos. 11-258572 and 2000-109376).
[0003]
This ceramic porous body has features such as low bulk specific gravity, high heat resistance, inertness, low airflow resistance, ie low pressure loss, etc., so it can be used for kitchen grease filters, catalyst carriers, breathable heat insulating materials, molten metal. Although it is used for filter media, it is required that the pressure loss be as low as possible when used in these applications.
[0004]
Conventionally, in order to reduce the pressure loss, the degree of adhesion of the ceramic slurry to the polyurethane foam has been reduced. However, the apparent specific gravity of the ceramic porous body is reduced, and there is a problem in strength.
[0005]
[Patent Document 1]
JP-A-11-2857882 [Patent Document 2]
JP-A-2000-109376 [0006]
[Problems to be solved by the invention]
This invention is made | formed in view of the said situation, and it aims at providing the fluid filter which consists of a ceramic porous body which is excellent in dust removal performance and has low pressure loss.
[0007]
[Means for Solving the Problems]
The fluid filter of the present invention (Claim 1) has an outer cylindrical body made of a ceramic porous body, and an inner cylindrical body made of a ceramic porous body arranged inside the outer cylindrical body. The cylindrical body is a fluid filter that is a pleated cylindrical body meandering in the circumferential direction, and the outer cylindrical body and the inner cylindrical body are integrally sintered. .
[0008]
Fluid filter according the present invention has a flop Lietz form tubular body, filtering area is large, the pressure loss is small is excellent in dust removal performance.
[0009]
Further, since the flop Lietz form tubular body of this is disposed inside the cylindrical body, and to prevent breaking.
[0010]
The cylindrical body may be a cylindrical shape or a non-cylindrical cylindrical body.
[0011]
The ceramic porous body of the present invention is obtained by immersing a synthetic resin foam having a three-dimensional network skeleton structure having an internal communication space in a ceramic slurry to attach the ceramic to the synthetic resin foam, followed by drying and firing. A ceramic porous body having a three-dimensional network skeleton structure is preferred.
[0012]
The fluid filter of the present invention is suitable for removing dust such as air.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments and reference examples will be described below with reference to the drawings. 1A is a perspective view of a fluid filter according to a reference example , FIG. 1B is a cross-sectional view taken along line BB in FIG. 1A, and FIGS. 2 and 3 are diagrams for manufacturing the fluid filter of FIG. illustration of a method, Figure 4 is a perspective view of a fluid filter according to the form of implementation, Fig. 5 is a schematic view for illustrating a manufacturing method of the fluid filter of FIG. 4, FIG. 6 is a graph showing the pressure loss characteristics of the fluid filter.
[0014]
A fluid filter 1 shown in FIG. 1 includes a short cylindrical tubular body 2 and a corrugated plate-like filter body 3 disposed in the tubular body 2. The cylindrical body 2 and the filter body 3 are both made of a ceramic porous body and are an integral sintered body. The filter body 3 is arranged so as to block one end side (upper end side in FIG. 1) and the other end side (lower end side in FIG. 1) of the cylindrical body 2. The outer periphery of the filter body 3 is continuous with the inner periphery of the cylindrical body 2.
[0015]
The fluid filter 1 has a small pressure loss because the filter body 3 is corrugated and has a large filtration area. Although the corrugated ceramic porous body is easily damaged in this manner, the filter body 3 is disposed in the cylindrical tubular body 2, and the tubular body 2 protects the filter body 3. Damage to the filter body 3 is prevented.
[0016]
In order to manufacture the fluid filter 1, as shown in FIG. 2, corrugated foam 3 ′ and cylindrical foam 2 ′ each made of a synthetic resin foam having a three-dimensional network skeleton structure are manufactured. The plate-like foam 3 'is inserted into the cylindrical foam 2' to obtain a starting body. The starting body is immersed in a ceramic slurry, dried and fired. Thereby, the fluid filter 1 made of a ceramic porous body in which the filter body 3 and the cylindrical body 2 are integrally sintered is obtained.
[0017]
As shown in FIG. 3, the corrugated foam 3 ′ is manufactured by bending an elliptical synthetic resin foam sheet 3 ″ into a folded shape.
[0018]
Wave direction developed length of the filter body 3 and _{L 1,} which in the case where the orthogonal direction length was _{L 2,} that L 1 / _{L 2} is 2 to 10, in particular 3 to 5 especially about 4 Is preferred. As shown in FIG. 6, the airflow pressure loss of the fluid filter 1 is minimized when L ₁ / L ₂ is about 4.
[0019]
The lengths L ₁ and L ₂ correspond to the major axis and minor axis of the synthetic resin foam sheet 2 ″ in FIG. 3 when the firing shrinkage during firing is ignored. In the product of the fluid filter 1, road length of the wave direction of the surface of the filter body 3 is L _1, the inner diameter of the cylindrical body 2 is L _2.
[0020]
When the inner diameter of the cylindrical body 2 of the fluid filter 1 is D and the length of the cylindrical body 2 in the cylinder axial direction is W, D / W is 1.0 to 7.0, particularly 1.3 to 3. About 0.0 is preferable.
[0021]
When used as a gas filter, the thickness of the filter body 3 is preferably about 1.0 to 10.0 mm. The thickness of the cylindrical body 2 is preferably about 10 to 70 mm, particularly about 30 to 50 mm. The cylindrical body 2 is preferably stronger than the filter body 3.
[0022]
Any synthetic resin foam may be used as long as it has a three-dimensional network skeleton structure having an internal communication space, but a flexible polyurethane foam, particularly a flexible polyurethane foam having no cell membrane, can be preferably used. This polyurethane foam without cell membranes can be obtained by removing the cell membrane by controlling at the time of foaming, or by removing the cell membrane by alkali treatment, heat treatment, water pressure treatment, etc., and the number of cells, porosity, etc. Physical properties can be selected according to the application.
[0023]
As described above, the fluid filter 1 made of a ceramic porous body is obtained by immersing a synthetic resin foam in a ceramic slurry, adhering the ceramic slurry to the synthetic resin foam, drying and firing, and then heating the synthetic resin foam. Obtained by decomposition or incineration.
[0024]
Examples of the ceramic include oxide ceramics such as alumina, silica, and cordierite, and non-oxide ceramics such as silicon carbide and silicon nitride.
[0025]
Clay can be added to increase the stability of the ceramic slurry. As this clay, for example, Kibushi clay and Sasame clay can be used. Moreover, it is preferable that a compounding quantity shall be 0 to 15% with respect to all the ceramic components. If it exceeds 15%, the thixotropy index changes and causes clogging.
[0026]
In addition, the thixotropy can be adjusted by adding a binder such as polyvinyl alcohol and carboxymethyl cellulose to the ceramic slurry as required.
[0027]
The viscosity of the ceramic slurry can be adjusted by adjusting the amount of water added according to the size of the target ceramic porous body cell.
[0028]
Next, a starting body made of a synthetic resin foam having a three-dimensional network skeleton structure is immersed in the above-described ceramic slurry, excess slurry is removed, dried, and fired at a temperature of about 1000 to 1500 ° C. in a firing furnace. Thereby, the fluid filter which consists of a ceramic porous body of the three-dimensional network skeleton structure which has the internal communication space of the cell structure corresponding to a synthetic resin foam can be obtained.
[0029]
In order to make the cylindrical body 2 stronger than the filter body 3, the average pore diameter of the synthetic resin foam may be selected so that the skeleton of the cylindrical body 2 is thick.
[0030]
In addition, it is preferable that the filter main body 3 of the fluid filter 1 has 10 to 50 pores / 25 mm and a porosity of 75 to 90%.
[0031]
The cylindrical body 2 preferably has 5 to 50 holes / 25 mm and a porosity of 75 to 90%.
[0032]
Next, a description will be given fluid filter 5 according to the embodiment thereof with reference to the implementation of FIGS.
[0033]
The fluid filter 5 includes a cylindrical outer cylindrical body 6 and an inner cylindrical body 7 disposed in the outer cylindrical body 6. The inner cylindrical body 7 has a pleated shape meandering in the circumferential direction. The outer cylindrical body 6 and the inner cylindrical body 7 have the same length in the cylinder axis direction.
[0034]
In order to manufacture the fluid filter 5, as shown in FIG. 5, the inner cylindrical foam 7 ′ is inserted into the outer cylindrical foam 6 ′ as a starting body, and the starting body is immersed in a ceramic slurry. Dry and fire. Thereby, the fluid filter 5 which consists of a sintered compact integrated as a whole is obtained.
[0035]
In this fluid filter 5, when the circumferential length of the outer peripheral surface of the inner cylindrical body 7 is M ₁ and the peripheral length of the inner peripheral surface of the outer cylindrical body 6 is M ₂ , M ₁ When / M ₂ is ₂ to 10, particularly 3 to 5, especially about 4, the pressure loss is small.
[0036]
In this fluid filter 6, the fluid is filtered from the inside of the internal cylindrical body 7 through the internal cylindrical body 7 and the external cylindrical body 6, or from the outside of the external cylindrical body 6 to the outside. It passes through the cylindrical body 6 and the internal cylindrical body 7, is filtered, and is taken out from the inside of the internal cylindrical body 7.
[0037]
In the fluid filter 5, the inner cylindrical body 7 is pleated and has a large filtration area. Therefore, the fluid filter 5 has a low pressure loss by making the outer cylindrical body 6 have a low pressure loss with large pores. Further, since the inner cylindrical body 7 is protected by the outer cylindrical body 6, damage to the inner cylindrical body 7 is prevented.
[0038]
In addition, it is preferable that the internal cylindrical body 7 is 10-50 holes / 25mm in number of holes, and has a porosity of 75-90%. The outer cylindrical body 6 preferably has 5 to 50 holes / 25 mm and a porosity of 75 to 90%.
[0039]
The length of the fluid filter 5 in the cylinder axis direction is preferably about 0.1 to 2.5 times the diameter (outer diameter of the outer cylindrical body 6).
[0040]
In the above embodiment, the cylindrical bodies 6 ′ and 6 ′ are cylindrical, but they may be elliptical cylindrical, triangular or quadrangular or more polygonal cylindrical bodies.
[0041]
Next, pressure loss measurement results obtained by manufacturing the fluid filter 1 shown in FIG. 1 will be described.
[0042]
Fluid filter 1 of this are those prepared in the following manner.
[0043]
That is, 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 were mixed to prepare a ceramic slurry.
[0044]
Further, a filter body foam 3 ′ was manufactured from a sheet-like flexible polyurethane foam having a three-dimensional network skeleton structure having a cell length of 480 mm, a minor diameter of 120 mm, and a thickness of 7 mm, each having 30 cells per inch (25 mm). . A cylindrical foam 2 made of a flexible polyurethane foam having a three-dimensional network skeleton structure without a cell membrane having a cylindrical shape with an outer diameter of 130 mm, an inner diameter of 120 mm, and a length of 52 mm with 25 cells per inch (25 mm). 'I made. A polyurethane foam starting material was produced by fitting these together. This starting material was immersed in the slurry. Excess slurry was removed, the slurry was sufficiently dried, and then fired at 1300 ° C. for 10 hours to obtain a ceramic porous body. The average porosity of the ceramic porous body is 80% for the filter body 3 and 80% for the cylindrical body 2. In addition, the outer diameter of the fluid filter after firing is 128 mm, the inner diameter is 116 mm, the length is 50 mm, and the thickness (wall thickness) of the cylindrical body 2 and the filter body 3 is 6 mm.
[0045]
In this other fluid filter 1 , a fluid filter was manufactured in the same manner as the fluid filter described above except that the number of waves of the filter body 3 was varied by changing the major axis of the filter body foam 3 ′.
[0046]
Pressure loss was measured by circulating dust-containing air through each fluid filter at a wind speed of 3 m / sec. As the dust-containing air, air containing 0.08 g / m ^{3 of} JIS-12 type dust was used. The results are shown in FIG. As shown in FIG. 6, the pressure loss was minimized when L ₁ / L ₂ was about 4.
[0047]
【The invention's effect】
As described above, according to the present invention, a fluid filter with low pressure loss and hardly damaged is provided.
[Brief description of the drawings]
FIG. 1 (a) is a perspective view of a fluid filter according to a reference example , and FIG. 1 (b) is a cross-sectional view taken along line BB of FIG. 1 (a).
2 is an explanatory diagram of a method for manufacturing the fluid filter of FIG. 1. FIG.
3 is an explanatory diagram of a method for manufacturing the fluid filter of FIG. 1. FIG.
4 is a perspective view of a fluid filter according to an embodiment of implementation.
FIG. 5 is an explanatory diagram of a method for manufacturing the fluid filter of FIG. 4;
FIG. 6 is a graph showing pressure loss characteristics of a fluid filter.
[Explanation of symbols]
1,5 Fluid filter 2 Cylindrical body 3 Filter body 6 External cylindrical body 7 Internal cylindrical body

Claims (4)

An outer cylindrical body made of a ceramic porous body, and an inner cylindrical body made of a ceramic porous body disposed inside the outer cylindrical body,
The inner tubular body is a fluid filter that is a pleated tubular body that meanders in the circumferential direction ,
The fluid filter, wherein the outer cylindrical body and the inner cylindrical body are integrally sintered. Oite to claim 1, the circumferential direction of the road length of the outer surface of the internal cylindrical body and M _1, if the circumferential length of the inner peripheral surface of the external tubular body and the M _2, M 1 _/ M ₂ Is a fluid filter, characterized in that it is 2-10. In claim _2, the fluid filter, characterized in that M 1 / _{M 2} is 3-5. In any one of claims 1 to 3, the ceramic porous body, a synthetic resin foam of a three-dimensional network skeleton structure having an internal communication space is immersed in a ceramic slurry by adhering the ceramic to the synthetic resin foam And a ceramic porous body having a three-dimensional network structure obtained by drying and firing.

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