JP2018030124A - Deodorization filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a deodorization filter having high deodorization efficiency by improving a contact chance between an odorous component and a deodorant, capable of suppressing increase of a pressure loss, and used for removing odor generated during cooking.SOLUTION: There is provided a deodorization filter 1 used for removing odor generated during cooking. The deodorization filter 1 is a honeycomb structure having a plurality of cells 14 partitioned by bulkheads 12 and used as a flow passage for odor. In the deodorization filter 1, a cross sectional shape of a cell 14 in an approximately vertical direction to a flow direction of odor is an approximately triangular shape.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to a deodorizing filter. More specifically, the present invention relates to a deodorizing filter that removes odors in exhaust air from a kitchen or a food processing factory.

  When cooking food such as seafood or meat with an electric cooker or electromagnetic cooker, the exhaust generated during cooking includes smoke and oily smoke. The exhaust gas containing smoke and oily smoke causes odor. In recent years, houses and commercial areas are in close contact with each other, and odors generated from restaurants and food processing factories may enter the living environment. As a countermeasure, an air purifier equipped with a deodorizing filter has been installed. As such a deodorizing filter, an adsorbent composed of an adsorbent coated with a catalyst for adsorbing an odor component contained in exhaust gas, activated carbon, or the like is used.

  An example of the structure of the deodorizing filter is a honeycomb structure. Since the honeycomb-like structure has a large surface area, the honeycomb structure can be efficiently contacted with an odor component, so that a large amount of air can be processed in a short time.

  Various proposals have been made as a deodorizing filter composed of such a honeycomb structure. For example, Patent Document 1 has a plurality of through-holes whose cross-sectional shape is a quadrilateral, and a wall forming the through-hole protrudes at one end or both ends of the through-hole, and the cross-sectional area of the through-hole A honeycomb filter is proposed which is smaller at one end or both ends of the through-hole than at the other portions.

  Patent Document 2 proposes a deodorizing material obtained by dispersing and molding clay mineral having a tunnel structure in gypsum. Further, Patent Document 3 discloses a kneaded material containing a clay mineral having mesopores and a particle size of 100 μm or more, a pore-forming material composed of combustible powder, and a molding aid as necessary. A deodorizing material which has been sintered and has 1 to 10 μm macropores formed of a pore forming material has been proposed. According to these techniques, a deodorizing effect can be obtained semipermanently.

Japanese Patent Laid-Open No. 10-99648 JP 2002-95730 A JP 2006-198612 A

In the technology of Patent Document 1, by forming a protruding portion that protrudes toward the inside of the through hole at one or both ends of the filter, turbulence is generated during ventilation, and the chance of contact with the filter wall surface is increased. , Improving the deodorizing performance. However, the number of through holes is limited by providing the protrusions, and there is a limit to the improvement of the deodorizing effect by increasing the number of cells. In addition, pressure loss may increase due to the presence of the protrusion.
The deodorizing materials described in Patent Documents 2 and 3 require a large amount of deodorizing materials in order to cope with the recent increase in efficiency of the deodorizing effect that is required in recent years. There was a problem that the cost of the increased.

  Therefore, the present invention is a deodorizing filter that can effectively remove exhaust gas generated during cooking in a kitchen or a food processing factory, etc., and efficiently improves the contact opportunity between the odor component and the deodorizing material. An object is to provide a deodorizing filter having deodorizing efficiency and capable of suppressing an increase in pressure loss.

  As a result of intensive investigations, the present inventors have determined that the deodorizing filter is made of a honeycomb-like structure having a plurality of cells, and specifies the cross-sectional shape of the cells substantially perpendicular to the exhaust gas flow direction. It was found that the above-mentioned problem can be solved by adopting the shape, and the present invention has been completed.

That is, the present invention relates to the following (1) to (17).
(1) A deodorizing filter used for removing exhaust gas generated during cooking, comprising a honeycomb-like structure having a plurality of cells partitioned by a partition wall and serving as a passage for the exhaust gas, A deodorizing filter, wherein a cross-sectional shape of the cell in a direction substantially perpendicular to a flow direction of exhaust gas is a substantially triangular shape.
(2) The deodorizing filter according to (1), wherein the cross-sectional shape of the cell is a substantially equilateral triangle shape or a substantially right-angled isosceles triangle shape.
(3) The cross-sectional shape of the cell is a substantially equilateral triangle shape, and the contact area with the exhaust gas is 12.1 cm ² / cm ³ or more and 16.5 cm ² / cm ³ or less ( The deodorizing filter according to 2).
(4) The deodorizing filter according to (3), wherein the contact area is 12.4 cm ² / cm ³ or more and 13.5 cm ² / cm ³ or less.
(5) The deodorizing filter according to (3), wherein the contact area is 12.9 cm ² / cm ³ or more and 13.1 cm ² / cm ³ or less.
(6) The cross-sectional shape of the cell is a substantially right-angled isosceles triangle, and the contact area with the exhaust gas is 12.1 cm ² / cm ³ or more and 17.7 cm ² / cm ³ or less. The deodorizing filter according to (2).
(7) The deodorizing filter according to (6), wherein the contact area is 12.4 cm ² / cm ³ or more and 14.0 cm ² / cm ³ or less.
(8) The deodorizing filter according to (6), wherein the contact area is 12.6 cm ² / cm ³ or more and 13.7 cm ² / cm ³ or less.
(9) The deodorizing filter according to any one of (1) to (8), wherein the structure includes an adsorbent, and the adsorbent includes a hydrophobic zeolite.
(10) The deodorizing filter according to (9), wherein the content of the hydrophobic zeolite is 20 to 70% by mass.
(11) The deodorizing filter according to (10), wherein the content of the hydrophobic zeolite is 20 to 50% by mass.
(12) Content of the said hydrophobic zeolite is 20-30 mass%, The deodorizing filter as described in said (10) characterized by the above-mentioned.
(13) The structure includes an adsorbent, and the adsorbent is at least one selected from the group consisting of hydrophobic zeolite, natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite, and silica gel. The deodorizing filter according to any one of (1) to (8), which is contained in combination.
(14) The adsorbent is 10 to 50% by mass of hydrophobic zeolite, and 8 to 20% by mass of at least one selected from the group consisting of natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite and silica gel. It contains, The deodorizing filter as described in said (13) characterized by the above-mentioned.
(15) The adsorbent is 10 to 22% by mass of at least one selected from the group consisting of 10 to 22% by mass of hydrophobic zeolite, natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite and silica gel. It contains, The deodorizing filter as described in said (14) characterized by the above-mentioned.
(16) The adsorbent is 8 to 18% by mass of at least one selected from the group consisting of 10 to 18% by mass of hydrophobic zeolite, natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite and silica gel. It contains, The deodorizing filter as described in said (14) characterized by the above-mentioned.
(17) The deodorizing filter according to any one of (1) to (16), wherein the exhaust gas is an aldehyde-based gas.

  According to the present invention, an odor component can be removed with high deodorization efficiency, and an increase in pressure loss can be suppressed. In addition, the deodorizing filter of the present invention can be effectively used for removing exhaust gas generated during cooking in a kitchen or a food processing factory.

FIG. 1A is a partial perspective view for explaining an embodiment of the deodorizing filter of the present invention. FIG. 1B is an enlarged view of the I part of FIG. 1A as viewed from the front. FIG. 2 is an enlarged front view of another embodiment of the deodorizing filter of the present invention. FIG. 3 is an enlarged front view of the deodorizing filter manufactured in the comparative example. FIG. 4 is a diagram for explaining the deodorizing performance evaluation apparatus used in Test Examples 1 and 2. FIG. 5 is a graph showing the results obtained in Test Example 1. FIG. 6 is a graph showing the results obtained in Test Example 2. FIG. 7 is a diagram for explaining the apparatus used in Test Example 3. FIG. 8 is a graph showing the results obtained in Test Example 3. FIG. 9 is a graph showing the results obtained in Test Example 4.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.
FIG. 1A is a partial perspective view for explaining an embodiment of the deodorizing filter of the present invention, and FIG. 1B is an enlarged view of a portion I of FIG. 1A as viewed from the front.
As shown in FIGS. 1A and 1B, the deodorizing filter 1 of the present invention includes a honeycomb-like structure having a plurality of cells 14 that are partitioned by partition walls 12 and serve as exhaust gas flow passages.

  In the present invention, the cross-sectional shape of the cell 14 in a direction substantially perpendicular to the flow direction of the exhaust gas of the deodorizing filter 1 (hereinafter, simply referred to as “cell cross-sectional shape”) is a substantially triangular shape. Since the cross-sectional shape of the cell 14 of the deodorizing filter 1 is substantially triangular, the chance of contact between the exhaust gas and the deodorizing filter 1 can be improved, and the deodorizing efficiency can be increased efficiently. Further, even if the number of cells 14 increases, an increase in pressure loss can be suppressed.

  The cross-sectional shape of the cell 14 may be a substantially triangular shape formed by three substantially straight lines, but from the viewpoint of ease of forming a honeycomb-like structure, reduction of pressure loss, strength of the deodorizing filter, and the like. 1B or a substantially isosceles triangle shape as shown in FIG. 2 is preferable, and from the viewpoint of suppressing an increase in pressure loss, a substantially equilateral triangle shape is preferable. More preferred.

In the deodorizing filter 1 of the present invention, the number of cells 14 per square inch (hereinafter referred to as “the number of cells”) in a cross section substantially perpendicular to the flow direction of exhaust gas is 59 / inch ² or more. 120 / inch ² or less, preferably 64 / inch ² or more and 92 / inch ² or less, more preferably 69 / inch ² or more and 92 / inch ² or less. When the number of cells is 59 / inch ² or more, it is possible to suppress the passage of odor components in the exhaust gas flowing without being adsorbed by the deodorizing filter, and the number of cells is 120 / inch ² or less. By being, it is possible to suppress an excessive increase in pressure loss and achieve both high deodorization performance. Moreover, according to the preferable number of cells, it is possible to obtain high deodorization efficiency while keeping the manufacturing cost low.

More specifically, when the cross-sectional shape of the cell is a substantially equilateral triangle shape, the number of cells is preferably 66 cells / inch ² or more and 120 cells / inch ² or less, and 69 cells / inch ² or more, 92 cells / inch. Inch ² or less is more preferable, and 73 / inch ² or more and 92 / inch ² or less are more preferable. When the cross-sectional shape of the cell is a substantially right-angled isosceles triangle, the number of cells is preferably 59 cells / inch ² or more and 120 cells / inch ² or less, and 64 cells / inch ² or more, 90 cells / inch ^2. The following is more preferable, and 69 / inch ² or more and 90 / inch ² or less are more preferable.

  The thickness t of the partition wall 12 of the deodorizing filter 1 of the present invention is preferably 0.31 mm or more and 0.64 mm or less, more preferably 0.42 mm or more and 0.55 mm or less, 0.42 mm or more, 0. 47 mm or less is more preferable. When the thickness t of the partition wall 12 of the deodorizing filter 1 is 0.31 mm or more, the strength of the deodorizing filter can be secured, and the deodorizing filter and the odor component can be sufficiently in contact with each other, and the thickness t is 0.47 mm or less. If it exists, an increase in pressure loss can be suppressed.

  More specifically, when the cross-sectional shape of the cell is a substantially equilateral triangle shape, the thickness t of the partition wall 12 is preferably 0.33 mm or more and 0.64 mm or less, and 0.42 mm or more and 0.55 mm or less. Is more preferable, and 0.45 mm or more and 0.47 mm or less are still more preferable. When the cross-sectional shape of the cell is a substantially right-angled isosceles triangle, the thickness t of the partition wall 12 is preferably 0.31 mm or more and 0.64 mm or less, more preferably 0.46 mm or more and 0.55 mm or less. 0.46 mm or more and 0.49 mm or less is more preferable.

Moreover, when the cross-sectional shape of the cell 14 is a substantially equilateral triangle shape, the length of one side of the substantially equilateral triangle is preferably 3.5 mm or more and 4.8 mm or less, and 4.0 mm or more and 4.7 mm. The following is more preferable, and 4.0 mm or more and 4.6 mm or less are still more preferable. When the cross-sectional shape of the cell is a substantially right-angled isosceles triangle, the hypotenuse of this substantially right-angled isosceles triangle, that is, the length of the long side is preferably 4.6 mm or more and 6.7 mm or less. 3 mm or more and 6.4 mm or less are more preferable, and 5.3 mm or more and 6.2 mm or less are still more preferable.
By satisfy | filling said range of length, the raise of an excessive pressure loss can be suppressed and there can exist an effect of being compatible with high deodorizing performance.

In the present invention, the contact area with the exhaust gas obtained by the following equation, that is geometric surface area, 12.1 cm ² / cm ³ or more, preferably 17.7cm ² / cm ³ or less, 12.4 cm ² / More preferably, it is not less than cm ^{3 and not} more than 14.0 cm ² / cm ³ , more preferably not less than 12.6 cm ² / cm ^{3 and not} more than 13.7 cm ² / cm ³ . By satisfy | filling the range of said contact area, the raise of an excessive pressure loss can be suppressed and there can exist an effect of being compatible with high deodorizing performance.

  In the above formula, P represents the pitch and t represents the thickness of the partition wall.

More specifically, when the cross-sectional shape of the cell is a substantially equilateral triangle shape, the contact area of the deodorizing filter with the exhaust gas may be 12.1 cm ² / cm ³ or more and 16.5 cm ² / cm ³ or less. preferably, 12.4 cm ² / cm ³ or more, more preferably 13.5cm ² / cm ³ or less, 12.9 cm ² / cm ³ or more, more preferably 13.1 cm ² / cm ³ or less. When the cross-sectional shape of the cell is a substantially right-angled isosceles triangle, the contact area of the deodorizing filter with the exhaust gas is preferably 12.1 cm ² / cm ³ or more and 17.7 cm ² / cm ³ or less. More preferably, it is 0.4 cm ² / cm ³ or more and 14.0 cm ² / cm ³ or less, and further preferably 12.6 cm ² / cm ³ or more and 13.7 cm ² / cm ³ or less.

  The honeycomb structure constituting the deodorizing filter 1 of the present invention is obtained by molding and firing a clay having at least a binder (binder) and an adsorbent, and before firing the clay. The binder and adsorbent are contained, and after firing, the binder is removed.

  Examples of the binder include methyl cellulose, polyvinyl alcohol, polyethylene glycol, acrylic resin, and the like. One kind may be used alone, or two or more kinds may be used in combination. Of these, methylcellulose is preferably used from the viewpoint of extrusion moldability and cost.

  The content of the binder is preferably 7% by mass or more and 17% by mass or less in the clay, more preferably 7% by mass or more and 10% by mass or less, and more preferably 7% by mass or more and 9% by mass or less. Further preferred. If the content of the binder is 7% by mass or more, good extrusion moldability can be obtained, and if it is 17% by mass or less, the strength for deodorizing filter use can be sufficiently secured.

  Examples of the adsorbent include natural zeolite, hydrophobic zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, silica, alumina, lime, gypsum, bitter lime, magnesium hydroxide, hydrotalcite, perlite, Portland cement, and alumina cement. And artificial zeolite and silica gel obtained by treating sepiolite, palygorskite, aluminum silicate, activated clay, activated alumina, bentonite, talc, kaolin, mica, coal ash and the like. These adsorbents may be used alone or in combination of two or more.

  In the present invention, since the hydrophobic zeolite has a characteristic that it is difficult to adsorb water, it is excellent in the adsorption power of exhaust gas generated especially during cooking. Preferably, from the viewpoint of practical strength and deodorizing performance as a deodorizing filter, and cost, the group consisting of (1) hydrophobic zeolite and (2) natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite and silica gel It is more preferable to use in combination with at least one selected from the above (hereinafter also referred to as (2) specific adsorbent).

  (1) Hydrophobic zeolite (2) When not used in combination with a specific adsorbent, the content is 20 mass% or more and 70 mass% or less in the structure obtained by firing the clay. It is preferable to make it 20 mass% or more and 50 mass% or less, and 20 mass% or more and 30 mass% or less are still more preferable. When the content of the hydrophobic zeolite is 20% by mass or more, it is preferable because it has sufficient deodorizing performance against cooking odors, and when it is 70% by mass or less, good extrudability and practical strength can be obtained. Therefore, it is preferable.

Further, when the adsorbent contains (1) a hydrophobic zeolite and (2) a specific adsorbent, (1) the hydrophobic zeolite is 10% by mass or more and 50% by mass in the structure obtained by firing the clay. It is preferable to contain so that it may become% or less, 10 mass% or more and 22 mass% or less are more preferable, and 10 mass% or more and 18 mass% or less are still more preferable. And (2) the specific adsorbent is preferably contained in the structure obtained by firing the clay so as to be 8% by mass or more and 20% by mass or less, and 8% by mass or more and 19% by mass or less. Is more preferable, and 8 mass% or more and 15 mass% or less are still more preferable.
Specifically, in the structure constituting the deodorizing filter, it is preferable to contain a combination of (1) 10-50% by mass of hydrophobic zeolite and (2) 8-20% by mass of a specific adsorbent. More preferably, the combination of ˜22 mass% and the latter is used in a combination of 8 to 19 mass%, the former is more preferably used in the combination of 10 to 18 mass%, and the latter is used in a combination of 8 to 15 mass%.

  In the structure which comprises the deodorizing filter of this invention, unless the effect of this invention is prevented, components other than the above can be contained. Examples of other components include catalysts and inorganic clay minerals.

  As the catalyst, a transition metal oxide is generally used. Examples of the transition metal oxide include titanium dioxide, vanadium oxide, manganese oxide, manganese dioxide, iron oxide, cobalt oxide, copper (I) oxide, copper (II) oxide, and molybdenum oxide. Or may be used in combination of two or more. Among these, it is preferable to use manganese dioxide from the viewpoint of compatibility with odor components contained in exhaust air of kitchens and food processing factories, and cost.

  Examples of inorganic clay minerals include montmorillonite, kaolinite, sepiolite, and palygorskite.

  Examples of other fillers include glass fibers.

  The production method of the deodorizing filter of the present invention may be any known method, and is not particularly limited. For example, a clay obtained by mixing a binder, water, an adsorbent, and other components is a predetermined mold. And a method of sequentially performing extrusion, drying and firing.

  The odor that the deodorizing filter of the present invention deodorizes is an odor generated during cooking. The exhaust gas generated during cooking contains odorous molecules such as aldehydes, fatty acids, hydrocarbons, alcohols, ketones or esters, and odorous components such as oily smoke substances. It is possible to deodorize with efficiency. The deodorizing filter of the present invention is particularly excellent in aldehyde-based gas adsorption and can provide an efficient removal effect.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further, this invention is not restrict | limited to the following example. In the following examples, “part” means “part by mass”.

(Example 1, Example 8 to Example 12)
For 2,000 parts of water, 430 parts of methylcellulose (viscosity: 3500-5600 cps), 430 parts of hydrophobic zeolite (ZSM-5 type), 600 parts of natural zeolite, 356 parts of sepiolite, 356 parts of palygorskite, 178 parts of silicon dioxide, 1256 aluminum oxide Part, 178 parts of silicate mineral, 544 parts of manganese dioxide and 210 parts of glass fiber were added with stirring and mixed until uniform to obtain a clay.

  The obtained clay was extruded into a predetermined mold to obtain a honeycomb-like structure having a regular triangular cross-sectional view as shown in FIG. 1B, which was dried and fired at 400 ° C. for 48 hours to obtain a deodorizing filter. Manufactured. The size of the obtained deodorizing filter was 100 cm long, 100 cm wide, and 200 cm long.

(Example 2)
For 2,000 parts of water, 446 parts of methylcellulose (viscosity: 3500-5600 cps), 835 parts of hydrophobic zeolite (ZSM-5 type), 410 parts of sepiolite, 410 parts of palygorskite, 200 parts of silicon dioxide, 1350 parts of aluminum oxide, silicate mineral 200 parts, 564 parts of manganese dioxide and 218 parts of glass fiber were added with stirring and mixed until uniform to obtain a clay.
Using the obtained clay, a deodorizing filter was produced in the same manner as in Example 1.

(Example 3)
2,000 parts of methyl cellulose (viscosity: 3500-5600 cps), 1280 parts of hydrophobic zeolite (ZSM-5 type), 350 parts of sepiolite, 350 parts of palygorskite, 188 parts of silicon dioxide, 1230 parts of aluminum oxide, silicate mineral 161 parts, manganese dioxide 492 parts, and glass fiber 190 parts were added with stirring and mixed until uniform to obtain a clay.
Using the obtained clay, a deodorizing filter was produced in the same manner as in Example 1.

Example 4
2,000 parts of water, 640 parts of methylcellulose (viscosity: 3500-5600 cps), 2005 part of hydrophobic zeolite (ZSM-5 type), 110 parts of sepiolite, 110 parts of palygorskite, 186 parts of silicon dioxide, 1135 parts of aluminum oxide, silicate mineral 134 parts and 312 parts of glass fiber were added under stirring and mixed until uniform to obtain a clay.
Using the obtained clay, a deodorizing filter was produced in the same manner as in Example 1.

(Example 5)
Methyl cellulose (viscosity: 3500-5600 cps) 384 parts, hydrophobic zeolite (ZSM-5 type) 2990 parts, sepiolite 110 parts, palygorskite 110 parts, silicon dioxide 150 parts, aluminum oxide 640 parts, silicate mineral 80 parts and 187 parts of glass fiber were added under stirring and mixed until uniform to obtain a clay.
Using the obtained clay, a deodorizing filter was produced in the same manner as in Example 1.

(Example 6)
2,000 parts of water, 349 parts of methylcellulose (viscosity: 3500-5600 cps), 2088 parts of hydrophobic zeolite (ZSM-5 type), 804 parts of natural zeolite, 89 parts of sepiolite, 89 parts of palygorskite, 102 parts of silicon dioxide, 772 aluminum oxide Part, 73 parts of silicate mineral, and 171 parts of glass fiber were added with stirring and mixed until uniform to obtain a clay.
Using the obtained clay, a deodorizing filter was produced in the same manner as in Example 1.

(Example 7)
2,000 parts of methyl cellulose (viscosity: 3500-5600 cps), 883 parts of hydrophobic zeolite (ZSM-5 type), 773 parts of natural zeolite, 199 parts of sepiolite, 199 parts of palygorskite, 196 parts of silicon dioxide, 1386 aluminum oxide with respect to 2000 parts of water Part, 196 parts of silicate mineral, and 232 parts of glass fiber were added with stirring and mixed until uniform to obtain a clay.
Using the obtained clay, a deodorizing filter was produced in the same manner as in Example 1.

(Example 13 to Example 18)
2,000 parts of methyl cellulose (viscosity: 3500-5600 cps), 720 parts of hydrophobic zeolite (ZSM-5 type), 360 parts of molecular sieve, 360 parts of sepiolite, 360 parts of palygorskite, 180 parts of silicon dioxide, 1260 aluminum oxide Part, 180 parts of silicate mineral, 540 parts of manganese dioxide and 210 parts of glass fiber were added with stirring and mixed until uniform to obtain a clay.
The obtained clay is extruded into a predetermined mold to obtain a honeycomb-like structure having a right isosceles triangle shape as shown in FIG. 2, which is dried and fired at 400 ° C. for 48 hours to produce a deodorizing filter. did. The size of the obtained deodorizing filter was 100 cm long, 100 cm wide, and 200 cm long.

(Comparative Examples 1-3)
Using a clay having the same formulation as in Example 13, this was extruded into a predetermined mold to obtain a square honeycomb structure as shown in FIG. 3, which was dried and then dried at 400 ° C. for 48 hours. Firing and producing a deodorizing filter. The size of the obtained deodorizing filter was 100 cm long, 100 cm wide, and 200 cm long.

About the obtained deodorizing filter, the number of cells, partition wall thickness, pitch, opening area, opening ratio, and contact area were measured and calculated, respectively.
<Number of cells>
As the number of cells, the number of cells per square inch in the cross-sectional shape was measured.
<Partition wall thickness (mm)>
The partition wall thickness in the cross-sectional shape was measured as the partition wall thickness.
<Pitch (mm)>
As the pitch, the length of one side of the opening was measured for regular triangular and square cells, and the length of the hypotenuse of the cell was measured for right-angled isosceles triangular cells.
<Opening area (mm ² )>
As the opening area, the total area of the cell openings was measured.
<Opening ratio (%)>
As the aperture ratio, the ratio of the total area of the cell openings to the cross-sectional area of the deodorizing filter in the cross-sectional shape was determined.
<Contact area (cm ² / cm ³ )>
The contact area (geometric surface area) was determined by the following formula.

  In the above formula, P represents the pitch and t represents the thickness of the partition wall.

  The results are shown in Table 1.

  From the results shown in Table 1, when comparing the deodorizing filters of Examples 1 to 7, 9 and 13 with Comparative Example 2, the deodorizing filters of Examples 1 to 7, 9 and 13 are almost the same in number of cells. It can be seen that the contact area is significantly increased with respect to Comparative Example 2. This means that the contact opportunity with the odor component in the exhaust gas is efficiently improved and the deodorization efficiency is high.

<Test Example 1: Deodorization performance evaluation 1>
About the deodorizing filter manufactured in Examples 1-18 and Comparative Examples 1-3, the deodorizing performance was evaluated.
FIG. 4 is a diagram for explaining a deodorization performance evaluation apparatus used for the evaluation. In this evaluation apparatus, the odor component supplied from the standard gas cylinder 41 is adjusted to a predetermined flow rate by the mass flow controller (MFC) 42 and introduced into the pipe P1. On the other hand, air is also adjusted to a predetermined flow rate by the mass flow controller (MFC) 43 and introduced into the pipe P <b> 1 through the bubbling tank 44. Thereafter, both are mixed with each other in the pipe P1, and become SV (Space Velocity) to be measured. After the predetermined temperature and humidity are confirmed by the thermohygrometer 45, a part of the mixed gas is fractionated and introduced from the three-way cock 46 into a gas chromatograph (GC-FID) 47 equipped with an FID detector, and a deodorizing filter 48 The concentration of the inlet odor component is measured. On the other hand, another part of the mixed gas passes through the deodorizing filter 48 and is then separated and introduced from the three-way cock 49 into the GC-FID 47, and the concentration of the outlet odor component is measured.

Propionaldehyde was used as the odor component supplied from the standard gas cylinder 41, and the deodorization performance was evaluated under the conditions of a gas concentration of 20 ppm, SV18000 h ⁻¹ , gas temperature and humidity of 25 ° C. and 60% RH, and 60 minutes from the start of ventilation of the deodorization filter. After 15, 15, 30, 45, 60 minutes from the start of aeration, the gas after passing through the deodorizing filter was collected with a syringe, and the concentration of odor components was measured using a gas chromatography method (GC / FID). Deodorization performance was expressed as a removal rate determined by the following formula.
Removal rate (%) = {1− (concentration of odorous component contained in gas after passing through deodorizing filter / concentration of odorous component before passing through deodorized filter whose concentration has been adjusted)} × 100 (%)
The results are shown in Table 2 and FIG.

From the results of Table 2 and FIG. 5, it was shown that the deodorizing filter of the example had higher deodorizing performance than the comparative example. In particular, the deodorizing filter of the example showed a deodorizing performance equivalent to or higher than that of the deodorizing filter of Comparative Example 3 having 101 cells / inch ² . Moreover, in the case of Examples 2-5 which do not use (2) specific adsorbent, it turned out that a high removal rate can be obtained by containing 20 mass% or more of hydrophobic zeolites. Moreover, in Example 1 and Examples 6-7 which combined (1) hydrophobic zeolite and (2) specific adsorbent, (1) Hydrophobic zeolite is supplemented with (2) specific adsorbent, and high malodorous gas The result showed the removal rate. In Example 1 and Examples 8 to 11, and Example 13 and Examples 14 to 17 having different numbers of cells, there is no significant difference in the removal rate in the range of the contact area obtained, and are all equivalent to the comparative example? A higher removal rate was shown. In Examples 12 and 18, the contact area is high and the malodor gas removal rate is higher than that of the other examples, but the pressure loss is somewhat high, and the use may be limited. In view of the relative effect of improving the contact area, hydrophobic zeolite content rate, and malodorous gas removal rate, Example 1, Example 7-10, and Examples 13-16 are actual from the viewpoint of cost and strength as a deodorizing filter. It can be said that it is a typical combination.

<Test Example 2: Deodorization performance evaluation 2>
In Test Example 1, the deodorizing performance was evaluated in the same manner as in Test Example 1 using 10 ppm hexanal as an odor component instead of propionaldehyde.
The results are shown in Table 3 and FIG.

From the results of Table 3 and FIG. 6, it was shown that the deodorizing filter of the example had higher deodorizing performance than the comparative example even when the odor component was hexanal. In particular, the deodorizing filter of the example showed the same deodorizing performance as the deodorizing filter of Comparative Example 3 having 101 cells / inch ² cells. As in the case of propionaldehyde, it was found that (2) in Examples 2 to 5 in which no specific adsorbent is used, a high removal rate can be obtained by containing 20% by mass or more of hydrophobic zeolite. Moreover, in Example 1 and Examples 6-7 which combined (1) hydrophobic zeolite and (2) specific adsorbent, a high malodor gas removal rate is obtained by supplementing hydrophobic zeolite with (2) specific adsorbent. The result is shown. In Example 1 and Examples 8 to 12, and Example 13 and Examples 14 to 18 having different numbers of cells, there is no significant difference in the removal rate within the range of the contact area obtained, and are all equivalent to the comparative example? A higher removal rate was shown. In view of the relative effect of improving the contact area, hydrophobic zeolite content rate, and malodorous gas removal rate, Example 1, Example 7-10, and Examples 13-16 are actual from the viewpoint of cost and strength as a deodorizing filter. It can be said that it is a typical combination.

<Test Example 3: Deodorization performance evaluation 3>
The deodorizing efficiency of the deodorizing filters of Example 1 and Comparative Examples 1 and 2 was evaluated using the apparatus shown in FIG. The apparatus shown in FIG. 7 heats and cooks a predetermined amount of beef at an actual cooking site 51, guides exhaust gas generated by the cooking to a pipe P2 by an exhaust fan (not shown), passes the deodorization filter 52, and deodorizes the filter 52. This is to evaluate the odor concentration at the inlet 53 and the outlet 54 of the exhaust gas.
The evaluation was performed by a three-point comparison odor bag method. Specifically, all of the six odor judges determine the individual threshold value from the dilution factor when no odor is felt, and the odor concentration is calculated from the average of the remaining four individual threshold values obtained by cutting the upper and lower two of them. Asked. Deodorization efficiency is calculated | required by the following formula | equation.
Deodorization efficiency (%) = (Inlet odor concentration−Outlet odor concentration) / Inlet odor concentration × 100
The result is shown in FIG.

  From FIG. 8, it was found that Example 1 was superior in deodorizing efficiency at the same SV as compared with Comparative Examples 1 and 2, and in particular, it was found that the deodorizing performance was approximately twice that of Comparative Example 1. .

<Test Example 4: Evaluation of pressure loss>
The deodorizing filters manufactured in Examples 1 and 13 and Comparative Examples 1 to 3 were evaluated for pressure loss.
Specifically, the pressure loss was evaluated by measuring the pressure loss difference between the inlet side and the outlet side of each deodorizing filter using the apparatus shown in FIG. 4 in accordance with the surface speed of 2 to 5 m / s. .
The result is shown in FIG.

  From FIG. 9, both Example 1 and Example 13 have the same pressure loss as Comparative Examples 2 and 3, and the pressure loss is suppressed more in the deodorizing filter of Example 1 having a regular triangular cross section. I found out.

DESCRIPTION OF SYMBOLS 1 Deodorizing filter 12 Bulkhead 14 Cell 41 Standard gas cylinders 42 and 43 Mass flow controller (MFC)
44 Bubbling tank 45 Thermo-hygrometer 46, 49 Three-way cock 47 GC-FID
48 Deodorizing filter 51 Cooking site 52 Deodorizing filter 53 Inlet side inlet 54 Outlet side outlet P1, P2 Piping

Claims (17)

A deodorizing filter used for removing exhaust gas generated during cooking,
A honeycomb-like structure having a plurality of cells partitioned by partition walls and serving as a flow path for the exhaust gas;
The deodorizing filter, wherein a cross-sectional shape of the cell in a direction substantially perpendicular to a flow direction of the exhaust gas is a substantially triangular shape.   The deodorizing filter according to claim 1, wherein the cross-sectional shape of the cell is a substantially regular triangle shape or a substantially right-angled isosceles triangle shape. The cross-sectional shape of the cell is a substantially equilateral triangle shape, and a contact area with the exhaust gas is 12.1 cm ² / cm ³ or more and 16.5 cm ² / cm ³ or less. Deodorizing filter. The deodorizing filter according to claim 3, wherein the contact area is 12.4 cm ² / cm ³ or more and 13.5 cm ² / cm ³ or less. The deodorizing filter according to claim 3, wherein the contact area is 12.9 cm ² / cm ³ or more and 13.1 cm ² / cm ³ or less. The cross-sectional shape of the cell is a substantially right-angled isosceles triangle shape, and a contact area with the exhaust gas is 12.1 cm ² / cm ³ or more and 17.7 cm ² / cm ³ or less. Deodorizing filter as described in 2. The deodorizing filter according to claim 6, wherein the contact area is 12.4 cm ² / cm ³ or more and 14.0 cm ² / cm ³ or less. The deodorizing filter according to claim 6, wherein the contact area is 12.6 cm ² / cm ³ or more and 13.7 cm ² / cm ³ or less.   The deodorizing filter according to any one of claims 1 to 8, wherein the structure contains an adsorbent, and the adsorbent includes a hydrophobic zeolite.   The deodorizing filter according to claim 9, wherein the content of the hydrophobic zeolite is 20 to 70 mass%.   The deodorizing filter according to claim 10, wherein the content of the hydrophobic zeolite is 20 to 50% by mass.   The deodorizing filter according to claim 10, wherein the content of the hydrophobic zeolite is 20 to 30% by mass.   The structure contains an adsorbent, and the adsorbent contains a combination of hydrophobic zeolite and at least one selected from the group consisting of natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite, and silica gel. The deodorizing filter according to any one of claims 1 to 8, wherein:   10-50% by mass of the hydrophobic zeolite, and 8-20% by mass of at least one selected from the group consisting of natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite, and silica gel. The deodorizing filter according to claim 13, which is characterized by:   10 to 22% by mass of the hydrophobic zeolite, and 8 to 19% by mass of at least one selected from the group consisting of natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite and silica gel. The deodorizing filter according to claim 14, wherein   10 to 18% by mass of the hydrophobic zeolite, and 8 to 15% by mass of at least one selected from the group consisting of natural zeolite, hydrophilic zeolite, molecular sieve, diatomaceous earth, artificial zeolite and silica gel. The deodorizing filter according to claim 14, wherein   The deodorizing filter according to any one of claims 1 to 16, wherein the exhaust gas is an aldehyde-based gas.

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