JPH09170708A - Catalyst combustion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a carnation in combustion amount of a sufficient range to be realized without damaging a complete combustion by a method wherein a means for controlling a flow rate of fuel supplied to a per-mixing chamber and a movable closing means for closing a part of a communication hole of a combustion catalyst layer are substantially co-related to each other. SOLUTION: Fuel gas supplied from a fuel supplying pipe 1 is supplied to a per- mixing chamber 4 by sucking air under an ejector effect at a throat part 2 and adjusting its total amount at a combustion control part 3. Fuel and air mixed at the premixing chamber 4 are passed through the combustion catalyst layer 6 under their-reacted condition, ignited by an ignition device 5 and then a flame combustion is started at a downstream surface of the combustion catalyst layer 6. Then, combustion discharged gas of a high temperature heats a purifying catalyst layer 9 and concurrently heats the combustion catalyst layer 6 and then the temperature is gradually increased from the downstream surface side. At this time, a part of the communication hole of the combustion catalyst layer 6 is closed by a closing damper 7 so as to prohibit the pre-mixture gas flowed from the pre-mixing chamber 4 and to reduce an amount of pre-mixed gas. Accordingly, it is possible to realize a variation in amount of combustion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalytic combustion device using catalytic combustion.

[0002]

2. Description of the Related Art A number of catalytic combustion devices using a catalyst having an oxidation activity for a fuel mainly composed of hydrocarbon have been proposed in the past. This is performed by controlling the flow rate of a premixed air / fuel mixture.

[0003]

In the above-mentioned conventional equipment,
The control range of the combustion amount is limited by the type of fuel and the oxidation activity of the catalyst layer, and there is a drawback that it can be controlled only within a limited combustion amount range for a predetermined catalyst layer capacity. That is, because of the characteristic of catalytic combustion that the temperature of the catalyst layer increases / decreases according to the amount of fuel that reacts in the catalyst layer, the upper limit of the combustion amount per unit volume of the catalyst layer is the active component supported on the catalyst layer. It is regulated by the heat resistance limit temperature (for example, white metal), while the lower limit of the combustion amount is regulated by the lower limit temperature of reaction completion. Therefore, in the case of a fuel such as hydrogen or carbon monoxide which is easily oxidized at a low temperature, the catalyst layer temperature is from 100 ° C to 90 ° C.
Although it can be used up to about 0 ° C, the lower limit temperature is 400 ° C to 500 ° C for propane, butane, kerosene and the like for hydrocarbon fuels usually used for household use, and 650 ° C to 700 ° C for methane which is the main component of natural gas. Since the lower limit temperature is ℃ and the upper limit is about 900 ℃ which is the heat resistance limit, the upper limit of the combustion amount control range is 1 ℃.
When set to 00, the lower limit is limited to about 40 to 60.

On the other hand, when catalytic combustion is used as a domestic combustion device, when used as a heat source for heating or hot water supply, the control range of the combustion amount is preferably as wide as possible, and the upper limit is 10
The lower limit for 0 is at least 30, preferably 20 or less, and conventional catalytic combustion devices cannot meet this demand.

It is an object of the present invention to provide a catalytic combustion device that satisfies this need.

[0006]

In order to solve the above-mentioned problems, according to the invention of claim 1, a premixing chamber for mixing the fuel and the air whose inflow amount is controlled by the flow rate control unit, and the premixing chamber are arranged downstream thereof. And a combustion catalyst layer having a large number of communication holes,
A control means for controlling the flow rate control means is provided with a blocking means for blocking a part of the communication hole of the combustion catalyst layer (sequential partial blockage or partial instantaneous blockage of a predetermined area, upstream or downstream of the combustion catalyst layer). It is characterized in that the closing means is interlocked to perform opening / closing operations substantially corresponding to the level (not necessarily in proportional relation).

Further, in the second aspect, the exhaust flow passage installed on the downstream side of the combustion catalyst layer is divided into a plurality of parts, which substantially correspond to the control level of the flow rate control means (not necessarily a proportional relationship). Movable closing means for opening and closing the exhaust flow path of the section,
It is characterized in that it is opened and closed in conjunction with the flow control means.

According to a third aspect of the present invention, in the structure of the first or second aspect, a purification catalyst layer is provided on the downstream side of the combustion catalyst layer, and an ignition means (electric heater, discharge igniter) is provided between the two catalyst layers. Etc.) is arranged to perform an ignition operation when the movable closing means is released.

Further, in the present invention, the combustion catalyst layer and the means for supplying the fuel and the air to the combustion catalyst layer are divided into a plurality of parts, and the exhaust flow path includes one downstream side of the plurality of combustion catalyst layers. It is characterized in that it comprises a purification catalyst layer and controls the total flow rate by opening and closing the flow rate control means for the divided fuel and air.

According to a fifth aspect of the present invention, in the structure of the fourth aspect, ignition means is provided between the combustion catalyst layer and the purification catalyst layer,
When opening the flow control means to increase the fuel supply,
The feature is that it fires each time.

With the above construction, in the invention of claim 1, the closing means closes a part of the communication hole of the combustion catalyst layer when the flow control means reduces the amount of air and fuel to a predetermined value or less. Then, the passage of the premixed gas (when the upstream side is blocked) or the combustion exhaust gas (when the downstream side is blocked) is stopped. At this time, since the premixed gas flows only in the open portion of the combustion catalyst layer, the flow rate of the premixed gas per unit cross-sectional area (that is, the combustion amount per unit area of the combustion catalyst layer) is substantially increased, and the high temperature It becomes a high load combustion of and maintains stable catalytic combustion. On the contrary, when increasing the premixed gas flow rate from this state, by opening the closing means,
Combustion shifts and expands to the non-combustion part using the high-temperature combustion part as the ignition source, and then returns to full-scale combustion.

Further, in the invention of claim 2, the exhaust passage on the downstream side of the combustion catalyst layer is divided into a plurality (two passages or more may be provided according to the desired change in the combustion amount), and each passage is provided. If a means for closing the flow path is provided and the flow control means causes the amount of air and fuel to fall below a predetermined value,
A part of the divided exhaust flow path is closed. As a result, similarly to the first aspect, the premixed gas flows only in the combustion catalyst layer in the portion where the exhaust flow path is open, and high-temperature, high-load combustion is performed to maintain stable catalytic combustion. Although the combustion catalyst layer is single, the combustion / extinguishing operation can be performed to control the entire combustion amount as if the combustion units divided into a plurality are arranged. In addition, the reaction position of the combustion catalyst layer may be selected as desired (left or right / up or down, etc.). When increasing the flow rate of the premixed gas, open the closed exhaust flow path to transfer the combustion to the non-combustion part, using the high temperature combustion part as the ignition source, and return to full combustion. You can

According to the third aspect of the present invention, the purification catalyst layer is provided on the downstream side of the combustion catalyst layer, and the ignition means is arranged between both catalyst layers, so that the flame is generated on the downstream surface of the combustion catalyst at the start of catalytic combustion. The catalyst for combustion can be formed to heat the catalyst for combustion to be automatically transferred to catalytic combustion, and the flame can sufficiently heat the catalyst for purification to completely purify unburned components from the initial stage. Further, even when the combustion surface of the combustion catalyst layer is expanded by opening the closing means, the purifying action can be exhibited here until the transition to the steady combustion, so that clean exhaust gas characteristics can be secured at all stages of the combustion operation. . Further, by operating the ignition means when the closing means is released, it is possible to surely and promptly make a transition to catalytic combustion by flame formation / self-heating in the non-combustion portion of the combustion catalyst layer.

In a fourth aspect of the invention, contrary to the second aspect, the combustion catalyst layer and the passage for supplying the premixed gas to the combustion catalyst layer are divided, and the supply of the premixed gas is opened and closed. Combustion in the combustion catalyst layer can be started / stopped. When the premixed gas is supplied again to the combustion catalyst layer whose combustion has been stopped, the combustion load in the purification catalyst layer installed downstream (because the reaction here does not start in the initial stage) increases. However, since the temperature is raised, the temperature of the combustion catalyst layer can be raised by the heat radiation from the purification catalyst layer, and the catalytic combustion is shifted to the steady state (in the combustion catalyst layer).

Even in the above case, by providing the ignition means between the combustion catalyst layer and the purification catalyst layer, flame combustion is formed on the downstream surface of the combustion catalyst layer at the beginning of the initial combustion, and the combustion heat of the combustion is formed. Thus, the combustion catalyst layer can be heated to gradually shift to the catalytic combustion reaction, and the purification catalyst layer can be immediately preheated by the heat of flame combustion, enabling exhaust gas purification from the initial stage. At the same time when the closing means which is closed at the same time is opened or when the premixed gas supply means which is closed is opened, the non-combustion portion (here, the temperature of the combustion catalyst layer is lowered by operating the ignition means again. In the same manner as in the initial ignition, the reaction of gradually shifting from flame combustion to catalytic combustion is performed, and it is possible to quickly shift to steady full-scale combustion.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In order to carry out the present invention, a catalyst layer having a large number of communicating holes and having an oxidizing activity of hydrocarbons and carbon monoxide, an ignition device, a flow rate control device, etc. are indispensable, and if necessary, heat ray transmission. Materials, temperature sensors such as thermocouples, relays and timers, drive parts such as motors and solenoids are required, and well-known techniques can be used for these. For example, as the oxidation catalyst layer and the purification catalyst layer, a honeycomb carrier of metal or ceramic, or a braided body of ceramic fibers carrying an active component containing a precious metal such as platinum or palladium as a main component has been conventionally used. . Quartz glass, crystallized glass, or the like is generally used as a heat-resistant heat ray transmitting material in ordinary combustion equipment. Air or gas fuel can be supplied by using the supply pressure for gas fuel (such as cylinder gas or city gas) or by using an electric fan to pump the air. A throat nozzle using the Venturi effect utilizing the supply pressure of fuel gas is also used. For the flow rate control, a manual needle valve, an electric solenoid valve, or the like is used, and in the case of liquid fuel, an electromagnetic pump or the like is used. Other drive parts have manual lever operation,
There are also motor drives with automatic control. All of these are means that have been widely adopted from the past, and in the present invention, known techniques can be adopted for them. (First Embodiment) FIG. 1 is an overall sectional view of a catalytic combustion apparatus according to the present invention, and FIG. 2 is a combustion characteristic view thereof. In FIG. 1, 1 is a fuel supply pipe, 2 is a throat part that sucks air by the jet pressure of fuel, and 3 is a combustion control part that controls the flow rate of both and adjusts the combustion amount. Further, 4 is a premixing chamber, 5 is an igniter, and 6 is a combustion catalyst layer in which a noble metal of a white metal is supported on a ceramic honeycomb. Further, 7 is a closed damper that vertically slides close to the downstream surface of the combustion catalyst layer 6, and is operated by a damper drive unit 8. The damper drive unit 8 is circuit-connected so as to interlock with the combustion control unit 3. Reference numeral 9 is a purification catalyst layer which is installed on the downstream side of the combustion catalyst layer 6 so as to face it, and is a ceramic honeycomb on which a noble metal of white metal is carried as a main component. Further, 10 is a transmission window made of heat-resistant glass, which is installed so as to face the upstream side of the combustion catalyst layer 6.

Next, the operation and combustion characteristics of this embodiment will be described.

First, at the start of combustion, the closed damper 7 is in a fully open state, that is, in a state of being pulled up.
Then, the fuel gas supplied from the fuel supply pipe 1 (here, the city gas 13A containing methane as a main component is used) sucks air by the ejector effect when the fuel gas is ejected in the throat part 2, and the combustion control part 3 Then, the total amount is adjusted (actually, the amount of sucked air is changed by changing only the fuel supply amount) and then sent to the premix chamber 4. The fuel and air that have been sufficiently mixed in the premix chamber 4 initially pass through the combustion catalyst layer 6 without reaction, and are ignited by the igniter 5 to start flame combustion on the downstream surface of the combustion catalyst layer 6. The high temperature combustion exhaust gas flows downstream to heat the purification catalyst layer 9, but the flame formed at the same time also heats the combustion catalyst layer 6 and gradually raises the temperature from the downstream side thereof to a temperature at which catalytic combustion reaction is possible. Reach As a result, the mixed gas supplied from the premix chamber 4 gradually starts the oxidation reaction in the combustion catalyst layer 6, and the flame on the downstream surface disappears. When catalytic combustion is started,
Due to the heat of self-reaction, the temperature of the combustion catalyst layer is further raised, and eventually the reaction center position is moved to the vicinity of the most upstream surface (the surface facing the premixing chamber 4), where it is red-heated. The heat radiated from the combustion catalyst layer 6 which has been red-heated is heated / heated through the transmissive window 10 (or part of which is absorbed by the transmissive window 10 and radiated again as secondary radiant heat from here). Be offered.

As described above, at the start of this combustion, the closed damper 7 is in the fully open state, that is, in the state of being pulled up, and all the flow paths (communicating holes of the honeycomb) of the combustion catalyst layer 6 are open. Combustion control unit 3 after the start of catalytic combustion
It is set to send a signal to the damper drive unit 8 when it reaches a certain amount (here, about 60% of the maximum combustion amount) or less when it is controlled by. The closed damper 7 slidingly descends downward and the combustion catalyst layer 6
Block a part of the downstream surface of the. Since the flow of the premixed gas is obstructed at the part where the flow path is blocked by the blocking damper 7, the catalytic combustion reaction here is stopped, and the premixed gas is mixed with the combustion catalyst layer 6
Flows only to the open (non-closed) part of the where the combustion reaction occurs intensively. From this state, the combustion control unit 3 can reduce the premixture until the temperature of the combustion catalyst layer 6 reaches the vicinity of the lower limit of the reaction.

On the other hand, when the combustion amount is increased from the closed combustion state, a predetermined premixed gas supply amount (60 described above) is supplied.
%), The closed damper 7 is opened contrary to the above, and the premixed mixture starts to flow in the entire area of the combustion catalyst layer 6, so that the high temperature normally open portion is used as the ignition source. Combustion is transferred to the entire area, resulting in uniform combustion over the entire surface.

The characteristics at the time of combustion will be described with reference to FIG. In the present embodiment, the heat resistant upper limit temperature of the combustion catalyst layer 6 is about 900 ° C., and the lower limit temperature at which the complete reaction can be maintained is about 650 ° C. (both are the average temperatures of the combustion reaction center part). Maximum combustion amount (when the entire surface of the combustion catalyst layer 6 is used and the combustion load is increased to near the heat resistant upper limit temperature)
Assuming that the time is 100, the combustion temperature is about 60% and the lower limit temperature is 6
When the temperature approaches 50 ° C., and below that, the combustion reaction cannot be maintained, and the temperature rapidly decreases to extinguish the fire. Blocking the blocking damper 7 in this 60% combustion amount region (blocking area is about 40%)
Then, the combustion load per unit area of the combustion catalyst layer 6 becomes equal to that at the time of the maximum combustion, and the temperature returns to near the heat-resistant upper limit temperature. When the combustion amount is further reduced, the temperature gradually decreases, but complete combustion can be maintained up to a combustion amount of about 30%. Thus, while the combustion catalyst layer 6 was left fully open, only 100 to 60% of the combustion amount could be controlled (area A), but 100 to 30% (area A).
Up to + B), and it becomes possible to control a large amount of combustion according to the application. This effect is particularly effective when a fuel such as methane having a high complete reaction lower limit temperature (that is, low reactivity) is used, and the blockage damper 7 is successively arranged in a plurality of stages depending on the necessity of the combustion amount control range. It is also possible to operate.

Further, in this embodiment, the closing damper 7 is used.
Is provided on the downstream side of the combustion catalyst layer 6, but the same effect can be obtained even if it is provided on the upstream side, and the above effect is not impaired. Further, at the start of catalytic combustion, the igniter 5 installed downstream of the combustion catalyst layer 6 is operated here to form flame combustion and self-heat, but the flame is generated in the premixing chamber 4. Is formed and the combustion catalyst layer 6 is heated by the high-temperature exhaust gas (in this case, an operation of temporarily stopping the fuel supply and extinguishing the flame is required at the transition from the preheating stage to the catalytic combustion). ) Is also possible and does not affect subsequent operations and effects. However, as shown in the above-described embodiment, the structure in which the flame is formed on the downstream surface of the combustion catalyst layer 6 does not require a complicated structure or operation and is excellent in operability and economy.

When the combustion amount is increased, if the igniter 5 is energized at the same time when the closed damper 7 is opened, the unburned portion that has passed through the cooled non-combustion portion (the portion shielded by the closed damper 7) is not burned. It is more effective because the premixed air is ignited, the flame combustion is switched to the catalytic combustion as in the case of the initial ignition, and the entire state is restored to the uniform catalytic combustion promptly. With this configuration, when the closing damper 7 is slid down in a plurality of stages as described above,
Since it becomes possible to secure an arbitrary shielding area, the temperature of the red heat part of the combustion catalyst layer 6 hardly changes,
It is also possible to change only the red heat area in proportion to the amount of combustion. In the radiant combustion (heater) provided with the transmission window 10, it becomes possible to provide a highly convenient combustion device by proportionally correlating the actual combustion amount with the visual change in the red heat area. . Further, if the blockage damper 7 is arranged on the downstream side of the combustion catalyst layer 6, it can be used without being exposed to the high-temperature red heat portion and suffering thermal damage and without visually disturbing, and it is stable for a long period of time. Comfortable combustion control is possible. Further, by disposing the purifying catalyst layer 9 so as to face the downstream surface of the combustion catalyst layer 6, it is possible to effectively purify and remove unburned components under any condition after the initial ignition, and especially, the blockage damper 7 The final exhaust gas can always be kept in a clean state even in the situation where an incomplete reaction is likely to occur due to opening and closing. (Second Embodiment) A second embodiment of the present invention will be described. In this embodiment, the exhaust gas passage is divided,
It is characterized in that a movable damper for blocking a flow path is installed in a part of the structure so as to be opened and closed, and the basic performance of combustion is the same as that of the first embodiment. Therefore, the present embodiment will be described focusing on the difference.

FIG. 3 is a schematic sectional view of the present embodiment. In FIG. 3, exhaust passages 11 and 11 ′ divided into two are provided downstream of the combustion catalyst layer 6, and purification catalyst layers 9 and 9 ′ are arranged inside thereof. Further, igniters 5 and 5'are provided between the purification catalyst layers 9 and 9'and the combustion catalyst layer 6, respectively, and are slid vertically at the downstream ends of the exhaust flow paths 11 and 11 '. A closing damper 7 that can close one of the flow paths is arranged in association with the damper driving unit 8.

The operation at the start of combustion is the same as in the first embodiment, but when the combustion amount changes, the operation of the combustion control unit 3 corresponds to, for example, even when the same combustion amount is 50%, In the case of "combustion", the closed damper 7 is slid downward to close the exhaust flow passage 11 ', and only the upper half of the combustion catalyst layer 6 is burned. On the contrary, in the case of "lower combustion", the closed damper 7 is slid upward. The exhaust passage 11 is moved to close the exhaust passage 11, and the combustion catalyst layer 6 is combusted only in the lower half. Therefore, in addition to the wide control of the combustion amount, the selection of the combustion (red heat) position also depends on the application to the object to be heated (for example, lower combustion for foot heating, upper combustion for upper body heating, etc.). It can be carried out. In addition, the divided exhaust passages 11 and 11 'can be used as if there are two divided combustion portions, even though the combustion catalyst layer 6 is integrated, and the igniter 5 is provided inside each of them. By arranging 5 ', it is possible to freely ignite / extinguish. Thus, even if a fuel having a low reactivity such as methane is used, the combustion amount can be changed within a sufficiently large range, and the state of the combustion amount can be directly visually confirmed. (Third Embodiment) A third embodiment of the present invention will be described. Contrary to the second embodiment, the present embodiment is divided into a premixed gas supply portion on the upstream side of the combustion catalyst layer for open / close control, and an exhaust passage and a purification catalyst layer on the downstream side. Is characterized in that it is integrated. The basic combustion characteristics of each block are the same as those of the first and second embodiments, and this embodiment will be described with a focus on the difference.

FIG. 4 is a schematic horizontal sectional view of this embodiment. In FIG. 4, the combustion catalyst layers 6, 6 ', 6 ", the permeation windows 10, 10', 10" arranged opposite to each other on the upstream side thereof and the premixing chambers 4, 4 ', 4 "sandwiched between them are , A plurality of independent units are provided, and the stop valves 12, 12 ', 1 are provided in the flow path of the premixed gas supplied thereto.
2 ″. On the other hand, the combustion catalyst layers 6, 6 ′,
The downstream side of 6 ″ is integrated, and one purification catalyst layer 9 is arranged in the exhaust passage 11.

In this structure, from the start of combustion, in any unit (single or plural units are possible), the igniters 5, 5 ', 5 "are ignited to start flame combustion, and eventually the combustion catalyst layers 6, 6'. , 6 ", catalytic combustion is started.
When the stop valves 12, 12 ′, 12 ″ are opened and closed by the combustion control unit 3, combustion / extinguishing is performed in the unit corresponding to the stop valves 12, 12 ′, 12 ″, and combustion at any combustion amount / any position is possible. Restart from combustion stop (stop valve 12, ...
. (Opening), the combustion load on the purification catalyst 9 temporarily increases and the temperature also rises, which serves as an ignition source and cools the combustion catalyst layers 6 ,. . . However, it is preferable to energize the igniters 5, ... Each time to start the flame combustion. Since the stop valves 12, ... Are in a cooling atmosphere, there is no thermal performance deterioration or incomplete stopping of the premixed gas, and the combustion amount can be controlled reliably for a long period of time. Since the purification catalyst layer 9 is always in a heated state (as long as it burns in any unit), even if incomplete combustion occurs at the combustion catalyst layer 6 ... The purifying effect can be fully exerted and a clean exhaust gas state can be maintained.

In this embodiment, the stop valves 12, ... Are provided downstream of the throat section 2 for automatically sucking combustion air.
However, the combustion control unit 3 may control only the fuel supply amount and may be integrated with the stop valves 12, ... Or have a throat function downstream thereof, which does not impair the effects of the present invention. .

Although the present invention has been described with reference to an example in which the present invention is applied to a gas-fuel combustion heater, it goes without saying that the present invention is not limited to this. That is, the following cases are also included in the present invention. 1. It is also applicable when liquid fuel is used as the fuel type. In this case, a means for vaporizing the liquid fuel upstream of the premixing chamber is added. 2. The application of combustion heat can be applied to a hot water supply device for recovering heat from high-temperature exhaust gas, or for directly recovering heat from radiant heat from a catalytic combustion surface, or a heating medium heating device. Further, it can be applied to a cooking device or a dryer using radiant heating. By using catalytic combustion,
It is needless to say that the fact that the generation of nitrogen oxides can be reduced to almost zero and the clean exhaust gas characteristics can be realized is the same as that of the conventionally proposed catalytic combustion device. 3. Although a ceramic honeycomb is used as the carrier of the combustion catalyst layer and the purification catalyst layer, the material and shape thereof are not limited as long as they have a large number of communication holes through which the premixed gas can flow, and for example, ceramic or A metal sintered body, a metal honeycomb, a metal nonwoven fabric, a ceramic fiber braid, or the like can be used. As the active ingredient, a noble metal such as platinum, palladium, and rhodium is generally used, but a mixture of these metals or a mixed composition with another metal or an oxide thereof may be used. It is possible to select an active ingredient according to the type of fuel and use conditions. 4. When controlling the supply of fuel and air, only the fuel supply is actually controlled using the throat part, and the air is automatically sucked. However, when fuel and air are forcibly supplied by fans, etc. However, the same effect can be obtained by controlling the flow rate of both by the combustion control unit.

[0030]

As described above, the catalytic combustion apparatus according to the present invention can control a wide combustion amount range within a limited usable temperature range of the catalyst. Even if a fuel having such a low reactivity is used, the combustion amount can be changed in a sufficient range without impairing complete combustion, and it is effective in providing a combustion device for comfortable and efficient heat supply.

Further, particularly in the case of directly utilizing the radiant heat from the catalyst layer through the transmission window, it is possible to visually confirm the change in the combustion amount and also to provide the visual effect, and to realize clean and comfortable heating. Will be possible.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a combustor as a first embodiment of the present invention.

FIG. 2 is a combustion characteristic diagram of the combustor.

FIG. 3 is a schematic sectional view of a heater as a second embodiment of the present invention.

FIG. 4 is a schematic sectional view of a heater as a third embodiment of the present invention.

[Explanation of symbols]

 1 Fuel Supply Pipe 2 Throat Part 3 Fuel Control Part 4, 4 ', 4 "Premixing Chamber 5, 5', 5" Ignition Device 6, 6 ', 6 "Combustion Catalyst Layer 7 Closing Damper 8 Damper Drive Unit 9, 9 'Purification catalyst layer 10, 10', 10 "Transmission window 11, 11 'Exhaust channel

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Maenishi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Jiro Suzuki, 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. A premixing chamber for mixing fuel and air, a fuel flow rate control means for supplying the fuel to the premixing chamber, and a combustion catalyst layer having a large number of communication holes installed downstream of the premixing chamber. A movable closing means for closing a part of the communication hole of the combustion catalyst layer close to the upstream surface or the downstream surface of the combustion catalyst layer, wherein the flow rate control means and the closing means are substantially associated with each other. A catalytic combustion device characterized in that 2. A premixing chamber for mixing a fuel and air, a flow rate control means for the fuel supplied to the premixing chamber, and a combustion catalyst layer having a large number of communication holes installed downstream of the premixing chamber. The combustion catalyst layer is provided with a plurality of exhaust passages that are dividedly installed on the downstream side, and a passage closing means that closes a part of the plurality of exhaust passages, and the flow rate control means and the closing means are substantially the same. A catalytic combustion device characterized in that it is associated with the above. 3. A purification catalyst layer having a large number of communication holes on the downstream side of the combustion catalyst layer, and an ignition means between the previous combustion catalyst layer and the previous purification catalyst layer. The catalytic combustion device according to claim 1 or 2, wherein the ignition means is operated at the time of opening. 4. A combustion catalyst layer having a plurality of communication holes arranged in a plurality of divisions, a plurality of flow rate control means for independently controlling the amount of fuel supplied to each combustion catalyst layer, and each combustion catalyst. One exhaust flow path covering the entire downstream side of the bed,
It is characterized by comprising: a purification catalyst layer having a large number of communication holes provided in the exhaust passage, and an operating means for closing a part of the plurality of flow rate control means to change the total flow rate. Catalytic combustion device. 5. The ignition means is provided between the combustion catalyst layer and the purification catalyst layer, and the ignition means is operated when the fuel supply is restarted by the flow rate control means. Catalytic combustion device.