JPH03217706A - Method of purifying exhaust gas - Google Patents

Abstract

PURPOSE:To prevent outflow of unburnt gas to the open air by a method wherein a discharge route and a carrier are coated with paint generating heat through energization, the paint is energized to heat a catalyst, and unburnt exhaust gas is burnt and purified. CONSTITUTION:A discharge pipe 1 which is a part of a discharge route 1a comprises a plurality of through-holes 2, 2... connected with each other, a catalyst 4 carried on the energizing surface of exhaust gas 3 of the through-hole 2, a carrier 5 which carries the catalyst 4, and paint 6 with which a part of the discharge pipe 1 is covered and which generates heat through energization. The paint 6 is connected to a cord 8 through a silver solder 7, and the paint 6 is energized through the cord 8. For example, platinum, palladium, and rhodium, are used as the catalyst 4 according to a kind and the nature of unbunnt gas. The outer and inner surfaces on the upper stream side of the discharge pipe 1 are coated with the heat generating paint 6, through enegization of the heat generating paint 6, the upper stream side of the exhaust pipe 1 is heated, heat is transferred throughout the whole of the exhaust pipe 1, which is heated to temperature optimum to working of the catalyst 4. By the passage of the exhaust gas 3 through the through-holes 2 of the discharge pipe 1, unburnt gas in the exhaust gas 3 is burnt and purified.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention is applicable to chimneys, factory exhaust ports, and kitchen equipment (for combustion).
The present invention relates to a method for purifying unburned exhaust gas in the exhaust path of a prime mover, a heating appliance, etc.

[Conventional technology]

Traditionally, chimneys, factory exhaust vents, kitchen equipment (for combustion),
2. Description of the Related Art Items that generate exhaust gas, such as prime movers and heating equipment, are provided with exhaust paths for discharging the gas.

However, exhaust gas usually contains unburned gas (e.g., fish smoke, NOx, etc.) that has a strange odor or is harmful, and this unburned gas directly enters the atmosphere from the exhaust pipe that forms the exhaust path. This causes unpleasant feelings and environmental deterioration.

[Problem to be solved by the invention]

Therefore, it is an object of the present invention to provide a method for purifying exhaust gas that can prevent unburned gas having an unpleasant odor or toxicity from flowing out into the atmosphere.

[Means to solve the problem]

In order to achieve the above object, the present invention supports a catalyst on at least a part of a suitably shaped carrier that constitutes an exhaust path through which exhaust gas passes or is supported in an exhaust path, and A paint that generates heat when energized is applied to at least a portion of the path and the carrier, and by energizing the paint, the catalyst is heated to burn unburned exhaust gas, thereby purifying the exhaust gas. .

The carrier may be an exhaust pipe having one or more through holes.

[Effect]

Since the present invention has the above configuration, electricity is applied to the paint applied to at least a portion of the exhaust path and the carrier to cause the paint to generate heat, thereby heating the exhaust path and the catalyst to ensure purification of unburned gas. I can do it.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

In the figure, (1) is an exhaust pipe that constitutes a part of the exhaust path (1a), and has multiple through holes (2) (2),
..., applied to the catalyst (4) supported on the exhaust gas (3) passage surface of the through hole (2), the carrier (5) supporting the catalyst (4), and a part of the exhaust pipe (1). , consisting of a paint (6) that generates heat when energized.

The paint (6) is connected to a cord (8) via a silver solder (7), and the paint (6) is energized by this cord (8).

The temperature at which the catalyst (4) of the exhaust pipe (1) is heated is the same as that of the paint (6
) The temperature is controlled to the optimum temperature for the unburned gas to burn.

The paint (6) can be applied as appropriate, but since the catalyst (4) is supported on the inner surface of the exhaust pipe (1), that is, the through hole (2), the paint (6) can be applied on the outer surface. It is preferable to apply the catalyst over a somewhat wider area.
) is easy to control the heating temperature. For example, it is most preferable to apply it to the entire outer surface of the exhaust pipe (1).

As the catalyst (4), appropriate materials such as platinum, palladium, rhodium, etc. can be used depending on the type and properties of the unburned gas, and the material of the carrier (5) supporting the catalyst (4) is as follows: For example, ceramics, aluminum, glass, stainless steel, etc., and the structure of the carrier (5) include:
For example, a honeycomb-like structure, a fibrous structure, a mat, a felt, a scrubber-like structure, etc. can be used. In other words, the structure of the carrier may be tubular or fibrous, as long as it allows gas to pass through the gaps. The selection depends on the exhaust pressure of the exhaust gas, as will be described later.

The catalyst (4) absorbs exhaust gas (
It is necessary that it is supported on at least a part of the passage surface of 3), and preferably it is supported over the entire surface of the passage surface.

By energizing the heat-generating paint (6) of the exhaust pipe (1) configured as described above to generate heat, the exhaust pipe (1) and the catalyst (4) are heated to a temperature at which the catalyst (4) can work in an optimal state.
).

Furthermore, by heating the exhaust pipe (1), the exhaust gas (3) is naturally also warmed when passing through the through hole (2), so that the unburned gas itself becomes easier to burn.

Figures 1 to 3 show an exhaust pipe (1) that constitutes a part of the exhaust system of a heating appliance, and the exhaust gas (3) is formed in a honeycomb shape from the left side to the right side of the figure. It passes through the through holes (2) (2)...

The heat-generating paint (6) is applied to the upstream side (left side in the figure) of the outer and inner surfaces of the exhaust pipe (1).

Therefore, when the heat-generating paint (6) is energized, the upstream side of the exhaust pipe (1) is heated, and this heat is conducted throughout the exhaust pipe (1), thereby bringing the catalyst (4) to the optimum temperature for its operation. Then, the exhaust gas (3) is inserted into the through hole (2) of this exhaust pipe (1).
), the unburned gas in the exhaust gas (3) is combusted and purified.

In this example, platinum/rhodium was used as the catalyst (4), and the catalyst (4) was heated to 300°C using an exothermic paint (6).
By heating to a certain degree, the proportion of residual unburned gas after passing through the exhaust pipe (1) could be reduced by half compared to the conventional method.

Figure 4 shows the method according to the present invention used to purify unburned gas such as smoke and soot generated when fish (10) and beef are grilled in a heating cooker (9). .

(11) is a heating device, such as a gas fire or an electric heater, and when fish (lO), etc. is grilled with this heating device (11), unburned gas (12) remains in the exhaust gas (3). .

Unburned gas (L2) remaining in this heating cooker (9)
When passing through the exhaust pipe (1) installed at the top of the cooking device (9), the heated catalyst (4) passes through the energized exothermic paint (6).
) is purified and released into the atmosphere.

In this embodiment, a heat-generating paint (6) is applied to the entire outer surface of the exhaust pipe (1), and the exhaust pipe (1) and catalyst (4) are heated from the outside.

In this example, platinum/palladium was used as the catalyst (4), and the catalyst (4) was energized to generate a heat-generating paint (6
), the proportion of unburned gas remaining after passing through the exhaust pipe could be reduced by half compared to conventional methods.

Furthermore, as another example (not shown), a carrier having a structure like a nonwoven fabric (that is, fibers formed into a cotton shape) carrying a catalyst before the punching process is supported in the exhaust path, Unburned exhaust gas can also be purified by energizing the catalyst or the exhaust path using a heat-generating paint to generate heat.

In other words, when used in applications where the pressure during exhaust gas exhaust is high, in order to reduce pressure loss due to obstacles in the exhaust path, for example, honeycomb-shaped through holes are used; When used in low-pressure applications, it is also possible to use carriers with somewhat greater resistance from exhaust gas, such as carriers with a structure like nonwoven fabric before the punching process.

〔Effect of the invention〕

Since this invention has the above-mentioned configuration, electricity is applied to the paint applied to the exhaust path to cause the paint to generate heat, thereby heating the exhaust path and the catalyst, thereby eliminating unburned and harmful odors contained in the exhaust gas. It is possible to reliably burn the gas and prevent it from flowing into the atmosphere.

[Brief explanation of drawings]

Figures 1 to 3 show an exhaust pipe that constitutes a part of the exhaust system of a heating appliance, Figure 1 is a perspective view showing the whole, Figure 2 is an enlarged perspective view of the main part of Figure 1, FIG. 3 is a cross-sectional view of FIG. 1. FIG. 4 is a longitudinal sectional view of a heating cooker using the method according to the present invention. (la)...Exhaust route (1,)...Exhaust pipe (
2)...Through hole (3)...Exhaust gas (4)
... Catalyst (5) ... Carrier (6) ... Exothermic paint

Claims (1)

[Claims] 1. A catalyst is supported on at least a part of a suitably shaped carrier that constitutes an exhaust passage through which exhaust gas passes or is supported within the exhaust passage, , coating at least part of it with paint that generates heat when energized;
A method for purifying exhaust gas, characterized in that the paint is energized to heat the catalyst to combust unburned exhaust gas, thereby purifying the exhaust gas. 2. The method for purifying exhaust gas according to claim 1, wherein the carrier is an exhaust pipe having one or more through holes.