JPH10230135A - Catalyst heater and catalytic device using the catalytic heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a catalytic heater wherein purification performance is not decreased even if it is clogged with foreign matter while rise of temperature is quick and the purification capacity is large by a method wherein a catalytic layer is formed on a surface of an expanded metal base material, and the catalytic layer is heated by using heating when the expanded metal base material is electrically charged. SOLUTION: A catalytic heater 1 is constituted by providing a feeding terminal 2 at both ends of an expanded metal wherein a catalytic layer is formed on a surface. In this case, a base material 4 of the expanded metal is manufactured by expanding successively a stitch after feeding a hoop-like plate in order according to a cut width and stamping with a semicylindrical edge. After degreasing the base material 4 manufactured thus, self creening porcelain enamel as a catalyst is applied onto the surface. After drying, it is baked to prepare the catalytic heater. Since the catalyst heater 1 is less prone to be clogged with the foreign matter, and further when it is partially clogged with the foreign matter, it is not on the whole clogged and purification performance is prevented from being deteriorated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst heater for purifying indoor air by purifying odor components and oil smoke generated from cooking appliances, combustion appliances, garbage disposal appliances, and the like, or attaching to a cooling device or the like. The present invention relates to a catalyst device using the catalyst heater.

[0002]

2. Description of the Related Art Conventionally, odors and oily smoke generated from cooking appliances and garbage disposal machines are oxidatively decomposed by externally heating a honeycomb-shaped oxidation catalyst using a ceramic carrier disposed in an exhaust gas path. Things. Thus, the indoor air is kept clean.
In addition, an adsorbent and the oxidation catalyst are installed in a cooling device, etc. During cooling, the smoke and odor components of the tobacco contained in the room air are once adsorbed to the adsorbent, and the adsorbed components are oxidatively decomposed by intermittent heating. Thus, the indoor air is purified.

[0003]

The above conventional method has a problem that the temperature of the oxidation catalyst rises slowly and it takes a long time to reach the decomposition temperature. For example,
In the case of an oxidation catalyst using a ceramic carrier, the reason is that the heat capacity of the catalyst is large and the thermal conductivity of the ceramic is low. Further, when the catalyst has a honeycomb shape, the temperature distribution becomes non-uniform, and the contact efficiency between the exhaust gas and the catalyst deteriorates.
Further, when the honeycomb is clogged by foreign matter, the purifying ability of the portion is reduced, and the durability is also reduced.

[0004]

SUMMARY OF THE INVENTION The present invention provides a catalyst heater which forms a catalyst layer on the surface of an expanded metal substrate and utilizes heat generated when an electric current is applied to the expanded metal substrate.
This is a catalyst device using the catalyst heater.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a catalyst layer is formed on a surface of an expanded metal substrate, and the catalyst layer is heated by utilizing heat generated when the expanded metal substrate is energized. In addition, the catalyst heater has a rapid temperature rise, has a large exhaust gas purifying ability, and does not lower the purifying performance even if foreign matter is clogged.

[0006] In the invention described in claim 2, the expanded metal base material has a thickness, width, length, step width, LW, SW.
The catalyst heater is capable of freely setting the resistance value by adjusting at least one of them, and supplying an arbitrary electric power to the catalyst layer.

According to a third aspect of the present invention, the catalyst layer is composed of an undercoat layer formed on the surface of the expanded metal substrate and a catalyst supported on the surface of the undercoat layer, so that the purification ability is high. The catalyst heater has excellent durability.

According to a fourth aspect of the present invention, the catalyst layer is formed on the surface of the uneven layer formed of a porous coating film formed on the surface of the expanded metal substrate, so that the anchor effect due to the unevenness and the chemical effect can be improved. The catalyst heater can be used together with the bonding, has high adhesion between the expanded metal base material and the catalyst layer, and has excellent durability.

According to a fifth aspect of the present invention, the catalyst layer has an adsorbent and a noble metal catalyst, always adsorbs harmful components in exhaust gas, and periodically supplies electricity to the catalyst heater to adsorb harmful components. Is a maintenance-free catalyst heater that can decompose and simultaneously activate the adsorbent.

[0010] The invention according to claim 6 is a catalyst heater in which the expanded metal substrate is processed into a corrugated plate to increase the contact area per exhaust gas passage area and improve the purification performance of the catalyst. .

According to a seventh aspect of the present invention, there is provided an expanded metal base comprising a catalyst heater, insulators disposed on upper and lower surfaces of the catalyst heater, and holding metal fittings disposed on side surfaces of the catalyst heater. The exhaust gas passes through the mesh of the material, the pressure loss is small, and the catalyst device is excellent in efficiency.

[0012]

【Example】

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described. FIG. 1 is a plan view showing the configuration of the present embodiment. Reference numeral 1 denotes an expanded metal having a catalyst layer formed on its surface, and power supply terminals 2 are provided at both ends. The base material of the expanded metal 1 (hereinafter simply referred to as a base material) has a configuration shown in FIG. The base material is prepared by sequentially feeding the hoop-shaped plate 4 in accordance with the step width K and punching out the stitches 3 by punching with a kamaboko-shaped blade. here,
The center-to-center distance in the short direction of the mesh is SW, and the center-to-center distance in the long direction of the mesh is LW. In this embodiment, the thickness is 0.1 mm, LW is 3 mm, SW is 2 mm, L is 800 mm, and S is 20 mm.
mm. As the base material, a material having a large specific resistance is suitable. In particular, in consideration of characteristics as a heater, any of Fe—Cr—Al heat resistant steel and Ni—Cr heat resistant steel is particularly excellent. In the present embodiment, in order to match the coefficient of thermal expansion of the catalyst layer formed on the surface, a heat-resistant Fe—Cr—Al-based steel (NTK No. 4) having a relatively small coefficient of thermal expansion is used.
L (manufactured by Nippon Metal Industry).

After the substrate thus prepared is degreased, a self-cleaning porcelain containing manganese oxide (hereinafter referred to as SC porcelain) is applied as a catalyst on the surface thereof, dried and fired to form a catalyst heater. . In addition,
In this embodiment, the SC enamel is used as the catalyst layer, but the present invention is not limited to the SC enamel.

FIG. 3 shows the result of operating the catalyst heater having the above configuration. That is, FIG. 3 shows a comparison between the surface temperature of the oxidation catalyst having the conventional configuration and the surface temperature of the catalyst heater of this embodiment when heated at the same volume.
From this result, the catalyst heater of this embodiment reaches a temperature almost twice that of the conventional heater at the same electric capacity. That is,
The energy required to reach the catalyst activation temperature is half that of the conventional one. FIG. 4 shows the result of comparing the rate of temperature rise between the configuration of the present embodiment and that of the conventional configuration. As can be seen from FIG.
In this embodiment, the time until the temperature reaches 100 ° C. is 40 W at 100 W.
It is seconds, but the conventional one requires 7 minutes at 300W.

As described above, the catalyst heater of this embodiment is
Since the expanded metal is used as the base material, foreign substances are hardly clogged, and even if the foreign substances are partially clogged, they are not completely clogged and the purification performance is not reduced. Further, since the punching metal is used as the heater, the heat transfer efficiency to the catalyst layer is high, energy is saved, and the temperature rising speed is very fast.

At this time, since the punching metal is used as a heater for heating the catalyst layer, the resistance value can be freely set and a catalyst heater capable of supplying an arbitrary electric power to the catalyst layer can be easily realized. is there. That is, the resistance value can be changed by adjusting any of the thickness, width S, length L, and step width K, LW, and SW of the expanded metal base material 4. In this embodiment,
Using a base material (thickness = 0.1 mm) of Fe-Cr-Al heat-resistant steel (NTK No. 4L (manufactured by Nippon Metal Industry)), keeping SW constant and adjusting LW and step width K ing.
FIG. 5 shows how the sheet resistance of the substrate 4 changes as a result of the adjustment. As can be seen from FIG. 4, the step width K and the sheet resistance are substantially in inverse proportion, and the electric resistance decreases as the step width K increases. FIG. 6 shows the relationship between the length L and the resistance. As a matter of course, when the length L is increased, the electric resistance increases proportionally. Further, the width S and the resistance are in an inversely proportional relationship, and when the width S is increased, the sheet resistance decreases. (Not shown)
At this time, according to the test results of the inventors, LW: SW =
A ratio of 2: 1 or more is superior in terms of mechanical strength, but it is not particularly necessary to limit the ratio of LW to SW.

(Embodiment 2) Next, a second embodiment of the present invention will be described. FIG. 7 is a cross-sectional view illustrating the configuration of the present embodiment. In the present embodiment, the catalyst layer 7 is constituted by the undercoat layer 5 and the noble metal catalyst 6 supported on the undercoat layer 5. With this configuration, it is possible to realize a catalyst heater having excellent purification ability and durability. Hereinafter, the catalyst heater having this configuration will be described.

3.5 g of undercoat slurry on substrate 4
After the application, the coating is dried at 130 ° C. for 20 minutes and baked at 600 ° C. for 20 minutes to form the undercoat layer 5. Next, an aqueous solution of 4.5% by weight of dinitrodiamine platinum nitrate and an aqueous solution of 4.5% by weight of dinitrodiamine palladium nitrate were mixed at a ratio of 1/2,
Apply 3.5g. After that, it is dried at 130 ° C for 20 minutes,
For 20 minutes to form a noble metal catalyst layer 6 and a catalyst heater. The undercoat slurry is prepared by using a sintered oxide A described below. 720 parts by weight of aluminum hydroxide, 217 parts by weight of cerium nitrate hexahydrate, 38 parts by weight of barium carbonate, and 1520 parts by weight of ion-exchanged water are mixed and dried at 100 ° C. Then, after sintering continuously at 1000 ° C. for 60 minutes, it is cooled and pulverized. The sintered oxide A obtained in this way was
0 parts by weight, 50 parts by weight of aluminum nitrate 9-hydrate, 80 parts by weight of colloidal alumina, and 460 parts by weight of ion-exchanged water were pulverized with a 2-liter ball mill for 5 hours. (Tokyo Keiki) viscosity is 105CP /
An undercoat slurry having a temperature of 25 ° C. and an average particle size distribution of 4.1 μm (particle size measuring device manufactured by Shimadzu Corporation) was obtained.

With the above configuration, the catalyst layer 7 has a high noble metal concentration at the surface. For this reason, a catalyst heater having a higher purification ability of the catalyst than the conventional one and having excellent durability can be realized.

(Embodiment 3) Next, a third embodiment of the present invention will be described. FIG. 8 is a cross-sectional view illustrating the configuration of the present embodiment. In the present embodiment, a concavo-convex layer 8 made of a porous coating film is formed on the surface of the substrate 4, and the catalyst layer 9 is formed on the surface. In the case of this configuration, the anchor effect and the chemical bonding by the uneven layer 8 can be used in combination, and a catalyst heater with improved adhesion between the base material 4 and the catalyst layer 9 can be realized.

Hereinafter, this configuration will be described. Uneven layer 8
Examples thereof include a plasma sprayed layer of alumina or the like, a heat-resistant paint having irregularities, an SC paint, and an SC enamel for stainless steel. In this embodiment, an SC enamel for stainless steel is used.

SC enamel is a porous coating film mainly composed of a glass component, manganese oxide and clay, and has a catalytic action. A mixture of a 4.5% by weight aqueous solution of dinitrodiamineplatinic nitric acid and a 4.5% by weight aqueous solution of dinitrodiaminepalladium nitric acid in a ratio of 1: 2 was added to this surface.
Apply 5g. After that, it is dried at 130 ° C for 20 minutes, and then dried at 600 ° C for 2 minutes.
By baking for 0 minutes, the catalyst layer 9 is formed, and at the same time, a catalyst heater is formed. In the catalyst heater manufactured in this manner, a manganese oxide-based catalyst and a noble metal-based catalyst coexist, and the advantages of the respective catalysts act so that the catalyst activity is extremely excellent. Further, the coating film formed by the uneven layer 8 has an anchor effect due to the unevenness, and is firmly bonded between the base material 4 and the uneven layer 8 and between the uneven layer 8 and the catalyst layer 9. is there.

In the configuration shown in FIG. 8, when the catalyst layer 9 has a configuration having an adsorbent and a noble metal catalyst, it is highly effective when used in combination with a cooling device, an air purifier, or the like. This realizes a catalyst heater.

Hereinafter, this configuration will be described. When the purpose is to purify indoor air by minimizing the release of heat, as in a cooling device or an air purifier, it is necessary to avoid a configuration in which the catalyst layer is constantly heated. In the present embodiment, the catalyst layer 9 has a configuration in which an adsorbent such as zeolite and a noble metal catalyst are combined. The catalyst layer 9 is applied to the uneven layer 8 and baked in the same manner as described above.
The catalyst layer 9 containing the adsorbent generally has a weak bonding force and is easily peeled off. However, in this embodiment, since the uneven layer 8 is used, the unevenness between the base material 4 and the uneven layer 8 is increased. The layer 8 and the catalyst layer 9 are firmly connected by the anchor effect of the uneven layer 8.

The above-structured catalyst heater is mounted on a cooling device or an air purifier, and usually only adsorbs odor components with an adsorbent, and energizes the base material 4 at regular intervals to cause the catalyst layer 9 to act. To oxidatively decompose odor components and activate the adsorbent at the same time. Thus, it is possible to realize a catalyst heater that can maintain deodorization without maintenance.

(Embodiment 4) Next, a sixth embodiment of the present invention will be described. FIG. 9 is a perspective view showing the configuration of this embodiment. In this embodiment, the base material 4 is processed into a corrugated plate, and the catalyst layer 9 is formed on the surface. Corrugated plate height H
Is not particularly limited, but is set to 10 mm in this embodiment.

With this configuration, the contact area where the exhaust gas contacts the catalyst layer 9 when passing through the catalyst heater can be increased. As a result, in the case of the configuration of this embodiment, the purification performance by the catalyst can be improved.

(Embodiment 5) Next, a fifth embodiment of the present invention will be described. This embodiment relates to a catalyst device using the catalyst heater described in the fourth embodiment. FIG.
Reference numeral 0 is a perspective view showing the configuration of the catalyst device of this embodiment. 1
Reference numeral 0 denotes a catalyst heater in which a catalyst layer 9 is formed on the surface of a substrate processed into a corrugated plate, and has a power supply terminal 1 at both ends. On a side surface of the catalyst heater 10, a holding fitting 1 having an insulating material 12 is provided.
1 to prevent left and right blur while electrically insulating the catalyst heater 10. Insulating materials 13 are provided on the upper and lower surfaces of the catalyst heater 10 to prevent the catalyst heater 10 from moving vertically. Note that the insulating material 13 is set to a size such that an opening of the mesh of the base material can be secured. 14 is an insulator,
The power supply terminal 1 is taken out from here.

With the above configuration, a catalyst device having a catalyst heater having the features described in the first to fourth embodiments can be realized.

That is, since the expanded metal is used as the base material, foreign substances are hardly clogged, and even if the foreign substances are partially clogged, they are not completely clogged and the purification performance does not decrease. . Since the expanded metal is used as a heater, the catalyst layer 9
Thus, it is possible to realize a catalyst device having high heat transfer efficiency, energy saving, and a very fast temperature rising speed.

Further, the catalyst layer 9 is formed as an undercoat layer,
When composed of a noble metal catalyst supported on an undercoat, the surface part is in a state of high noble metal concentration, realizing a catalyst device with higher purification capacity of catalyst and excellent durability compared to conventional You can do it.

In the case where an uneven layer made of a porous coating film is formed on the surface of the substrate and a catalyst layer is formed on the surface, the anchor effect and the chemical bonding by the uneven layer are used together. Thus, a catalyst device having high adhesion between the substrate and the catalyst layer and excellent durability can be realized.

In the case where a concavo-convex layer made of a porous coating film is formed on the surface of the base material, and a catalyst layer composed of an adsorbent and a noble metal catalyst is provided thereon, a maintenance-free structure is obtained. A catalyst device capable of continuing deodorization can be realized.

Further, when the base material is processed into a corrugated plate and a catalyst layer is formed on this surface, the contact area between the exhaust gas and the catalyst can be increased, and when the exhaust gas passes therethrough. Since the pressure loss of the catalyst is low, it is possible to realize a catalyst device having extremely high purification performance.

[0035]

According to the first aspect of the present invention, a catalyst layer is formed on the surface of an expanded metal substrate, and the catalyst layer is heated by utilizing heat generated when the expanded metal substrate is energized. An object of the present invention is to realize a catalyst heater which rises quickly, has a large exhaust gas purification ability, and does not decrease its purification performance even when foreign matter is clogged.

In the invention described in claim 2, the expanded metal base material has a thickness, width, length, step width, LW, SW
As a configuration in which the resistance is set by adjusting at least one of the above, a resistance value can be freely set, and a catalyst heater that can supply arbitrary power to the catalyst layer is realized.

According to a third aspect of the present invention, the catalyst layer is composed of an undercoat layer formed on the surface of the expanded metal substrate and a catalyst supported on the surface of the undercoat layer, and has a high purification ability. Further, a catalyst heater having excellent durability is realized.

According to a fourth aspect of the present invention, the catalyst layer is formed on the surface of an uneven layer made of a porous coating film formed on the surface of the expanded metal substrate. This realizes a catalyst heater having high adhesion and excellent durability.

According to a fifth aspect of the present invention, the catalyst layer has an adsorbent and a noble metal catalyst, so that a maintenance-free catalyst heater can be realized.

According to the sixth aspect of the present invention, a catalyst heater in which the expanded metal substrate is processed into a corrugated plate, the contact area per exhaust gas passage area can be increased, and the purification performance of the catalyst is improved. Things.

According to a seventh aspect of the present invention, there is provided a catalyst heater according to any one of the first to sixth aspects, an insulator disposed on an upper surface and a lower surface of the catalyst heater, and an insulator disposed on a side surface of the catalyst heater. The exhaust gas passes through the mesh of the expanded metal base material, the pressure loss is small, and an efficient catalyst device is realized as a configuration including the holding metal fittings.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a catalyst heater according to a first embodiment of the present invention.

FIG. 2 is a plan view illustrating the configuration of an expanded metal substrate.

FIG. 3 is a characteristic diagram showing a relationship between an electric capacity supplied to a substrate and a catalyst temperature.

FIG. 4 is a characteristic diagram showing a relationship between a current supply time to a substrate and a catalyst temperature.

FIG. 5 is a characteristic diagram showing the relationship between the step width of the base material and the sheet resistance.

FIG. 6 is a characteristic diagram showing the relationship between the length of the base material and the resistance.

FIG. 7 is a sectional view showing the configuration of a second embodiment of the present invention.

FIG. 8 is a sectional view showing the configuration of a third embodiment of the present invention.

FIG. 9 is a perspective view showing the configuration of a fourth embodiment of the present invention.

FIG. 10 is a perspective view showing the configuration of a fifth embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Catalyst heater 4 Expanded metal base material 5 Undercoat layer 6 Catalyst 7 Catalyst layer 8 Concavo-convex layer 11 Holder 12 Insulating material 13 Insulating material

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Haruo Terai 1006 Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (7)

[Claims] 1. A catalyst heater for forming a catalyst layer on a surface of an expanded metal substrate and heating the catalyst layer using heat generated when a current is supplied to the expanded metal substrate. 2. The expanded metal substrate has a thickness, width,
The catalyst heater according to claim 1, wherein the resistance is set by adjusting at least one of length, step width, LW, and SW. 3. The catalyst heater according to claim 1, wherein the catalyst layer comprises an undercoat layer formed on the surface of the expanded metal substrate, and a catalyst supported on the surface of the undercoat layer. 4. The catalyst heater according to claim 1, wherein the catalyst layer is formed on a surface of an uneven layer formed of a porous coating film formed on a surface of the expanded metal substrate. 5. The catalyst heater according to claim 4, wherein the catalyst layer has an adsorbent and a noble metal catalyst. 6. The catalyst heater according to claim 1, wherein the expanded metal substrate is processed into a corrugated sheet. 7. A catalyst heater according to any one of claims 1 to 6, comprising: an insulator disposed on an upper surface and a lower surface of the catalyst heater; and a holding member disposed on a side surface of the catalyst heater. Catalyst device.