Exhaust gas treatment apparatus
The exhaust gas treatment device addresses the issue of device enlargement by integrating a heating and combustion system with controlled gas flow and calorific value to reduce catalysts, achieving compact size and efficient VOC removal.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- MURATA MFG CO LTD
- Filing Date
- 2025-12-03
- Publication Date
- 2026-07-23
AI Technical Summary
Conventional catalytic exhaust gas treatment devices require a large number of catalysts, leading to an increase in device size.
An exhaust gas treatment device that includes a heating portion, a combustion gas supply portion, and a catalyst portion, with controlled flow rate and calorific value, to mix and burn exhaust gas with combustion gas, reducing the need for multiple catalysts.
The device effectively reduces the overall size by minimizing the number of catalysts required and mitigates catalyst poisoning, maintaining efficient VOC removal.
Smart Images
Figure JP2025042127_23072026_PF_FP_ABST
Abstract
Description
Exhaust gas treatment device
[0001] The present invention relates to an exhaust gas treatment device, and particularly to an exhaust gas treatment device for treating exhaust gas containing volatile organic compounds (VOCs: Volatile Organic Compounds).
[0002] Conventionally, a catalytic exhaust gas treatment device has been used to detoxify volatile organic compounds in exhaust gas generated in the electronic component manufacturing process. In this device, the removal of volatile organic compounds is performed using a catalyst (for example, see Patent Document 1).
[0003] Japanese Patent Application Laid-Open No. 2004-8987
[0004] In conventional solutions, it may be required to arrange a plurality of catalysts. In that case, there is a problem that the number of catalysts required for exhaust gas treatment is large and the equipment becomes large.
[0005] An object of the present invention is to provide an exhaust gas treatment device capable of suppressing the enlargement of the device.
[0006] An exhaust gas treatment device according to an aspect of the present invention includes an exhaust gas passage portion having an exhaust gas inlet and an exhaust gas outlet, a heating portion provided in the exhaust gas passage portion, and a first catalyst portion provided on the exhaust gas outlet side of the heating portion in the exhaust gas passage portion. The exhaust gas treatment device further includes a combustion gas supply portion. The combustion gas supply portion is connected to the exhaust gas passage portion such that exhaust gas and combustion gas supplied from the combustion gas supply portion have a mixing region where they are mixed at a position on the exhaust gas inlet side of the first catalyst portion in the exhaust gas passage portion. The exhaust gas treatment device further includes a first control portion that controls the flow rate of the combustion gas supplied to the mixing region and a second control portion that controls the calorific value of the heating portion.
[0007] An exhaust gas treatment device according to another aspect of the present invention includes a heating portion that heats exhaust gas, a combustion gas supply portion that supplies and mixes combustion gas with the exhaust gas heated by the heating portion to burn the exhaust gas, and a first catalyst portion to which the mixed exhaust gas and combustion gas are supplied.
[0008] According to the present invention, an exhaust gas treatment device and an exhaust gas treatment method can be obtained that can suppress the increase in size of the device.
[0009] This is a schematic diagram of the exhaust gas treatment device according to the first embodiment of the present invention. This is a schematic diagram of the exhaust gas treatment device according to the second embodiment of the present invention. This is a schematic diagram of the exhaust gas treatment device according to the third embodiment of the present invention.
[0010] 1. First Embodiment (1) The exhaust gas treatment device 1 according to the first embodiment will be described using the schematic configuration diagram 1 of the exhaust gas treatment device. Figure 1 is a schematic configuration diagram of the exhaust gas treatment device according to the first embodiment of the present invention.
[0011] The exhaust gas treatment device 1 is a device for treating exhaust gas W1. The exhaust gas W1 includes, for example, volatile organic compounds (VOCs) and organosilicon compounds.
[0012] Exhaust gas W1 is a decomposition gas or combustion gas generated when organic substances such as binders contained in ceramic bodies or ceramic laminates are incompletely decomposed or burned during firing of ceramic bodies formed by shaping ceramic raw materials or ceramic laminates formed by stacking ceramic green sheets, for example, in the manufacturing process of ceramic electronic components.
[0013] The exhaust gas treatment device 1 includes a heating unit 2, a combustion gas supply unit 3, and a catalyst unit 4 (first catalyst unit). The exhaust gas W1 flows in the order of heating unit 2, combustion gas supply unit 3, and catalyst unit 4.
[0014] The heating unit 2 heats the exhaust gas W1 to a temperature in the range of 700 to 800°C.
[0015] The combustion gas supply unit 3 supplies combustion gas B1 to the exhaust gas W1 heated by the heating unit 2 and mixes them to burn the exhaust gas W1. As a result, VOCs contained in the exhaust gas W1 are effectively removed by combustion. Furthermore, some of the organosilicon compounds are burned, and some of the organosilicon compounds at high temperatures are adsorbed onto the surface of the cylindrical body, etc. By removing VOCs by combustion, the amount of VOCs processed by the downstream catalyst unit 4 can be reduced, and the reduction in organosilicon compounds reduces the effect of catalyst poisoning on the downstream catalyst unit.
[0016] The mixed exhaust gas W1 and combustion gas B1 pass through the catalyst section 4. As a result, the VOCs in the mixed gas of exhaust gas W1 and combustion gas B1, which have already had their VOCs reduced by combustion, are further reduced, thus removing the VOCs. Since the VOCs have been reduced in the previous stage, the amount of VOCs processed by the catalyst section 4 is reduced. In addition, by reducing the amount of organosilicon compounds, the amount of organosilicon compounds adhering to the surface of the oxidation catalyst 6 (described later) is reduced, which has the effect of maintaining the catalytic reaction with VOCs for a longer period of time. Here, "removal" means that the VOCs are reduced to below a predetermined standard value.
[0017] (2) In the detailed configuration diagram 1 of the exhaust gas treatment device 1, the exhaust gas treatment device 1 is represented as having a structure in which exhaust gas W1 flows from the right side to the left side of the diagram within a cylindrical member 20 (exhaust gas passage section). The cylindrical member 20 has an exhaust gas inlet 20A and an exhaust gas outlet 20B.
[0018] The cylindrical member 20 is divided into a first zone 21 and a second zone 22. The exhaust gas W1 flows from the first zone 21 to the second zone 22 (from the right side in Figure 1 to the left side in Figure 2). In other words, the first zone 21 is located upstream in the flow direction of the exhaust gas W1, and the second zone 22 is located downstream in the flow direction of the exhaust gas W1. The first zone 21 is the zone where the heated exhaust gas W1 is processed by mixing and burning the combustion gas B1. The second zone 22 is the zone where the mixed gas of exhaust gas W1 and combustion gas B1 is processed. More specifically, starting from a point downstream of the point where the combustion gas B1 merges with the exhaust gas W1, the area upstream from this point is the first zone 21, and the area downstream is the second zone 22.
[0019] The first zone 21 is provided with a heating unit 2 and a combustion gas supply unit 3. The heating unit 2 is located on the upstream side in the flow direction of the exhaust gas W1, and the combustion gas supply unit 3 is located on the downstream side in the flow direction of the exhaust gas W1.
[0020] A catalyst unit 4 is provided in the second zone 22. The catalyst unit 4 is located on the exhaust gas outlet 20B side of the heating unit 2 in the cylindrical member 20.
[0021] The heating unit 2 has a first heater 5. The first heater 5 directly heats the exhaust gas W1 sent to the first zone 21. The first heater 5 is composed of, for example, an electric heater or a heat exchanger. The first heater 5 is formed in a cylindrical shape and is provided on the inner circumferential surface of the cylindrical member 20. Specifically, the first heater 5 is provided near the exhaust gas inlet 20A of the cylindrical member 20.
[0022] The combustion gas supply unit 3 includes a blower 8 that supplies combustion gas B1 (e.g., air, oxygen) to the exhaust gas W1, and a combustion gas supply pipe 9. The combustion gas supply pipe 9 is positioned in a hole 10 provided in the cylindrical member 20. The combustion gas B1 supplied by the blower 8 is supplied to the inside of the cylindrical member 20 through the combustion gas supply pipe 9. Specifically, a mixing region A is secured in the cylindrical member 20 where the exhaust gas W1 and the combustion gas B1 supplied from the combustion gas supply unit 3 are mixed at a position on the exhaust gas inlet 20A side of the catalyst 4. A flow valve 11 is provided in the combustion gas supply pipe 9.
[0023] The catalyst unit 4 includes an oxidation catalyst 6 for decomposing VOCs and a second heater 7 for heating the oxidation catalyst 6. The oxidation catalyst 6 is a catalyst in which active components such as platinum, palladium, manganese, and cobalt are supported on ceramics such as alumina. The second heater 7 is composed of, for example, an electric heater or a heat exchanger. The second heater 7 is formed in a cylindrical shape and is provided on the inner circumferential surface of the cylindrical member 20. The second heater 7 heats the mixed gas passing through the oxidation catalyst 6 to a temperature in the range of 200 to 400°C.
[0024] The exhaust gas treatment device 1 further comprises a first control unit 31 that controls the flow rate of combustion gas B1 supplied to the mixing region A, and a second control unit 32 that controls the amount of heat generated by the heating unit 2. The first control unit 31 and the second control unit 32 are computer systems having a processor (e.g., CPU), a storage device (e.g., ROM, RAM, HDD, SSD, etc.), and various interfaces (e.g., A / D converter, D / A converter, communication interface, etc.). The control unit performs various control operations by executing a program stored in the storage unit (corresponding to part or all of the storage area of the storage device).
[0025] The first control unit 31 controls the flow valve 11 to adjust the ratio of VOCs (an example of a first component) contained in the exhaust gas W1 and targeted for reduction by the catalyst unit 4, and oxygen (an example of a second component) contained in the combustion gas B1 and reducing VOCs by reacting with them, to a predetermined ratio. The flow rate of the exhaust gas W1 and the amount of VOCs contained in the exhaust gas W1 are input to the first control unit 31 either in advance or in real time.
[0026] The second control unit 32 controls the first heater 5 to raise the temperature of the exhaust gas W1 so that it reaches the reaction temperature at which the organic silicone compound and oxygen react in the predetermined ratio described above. The reaction temperature is, for example, in the range of 700 to 800 degrees Celsius.
[0027] (3) Exhaust gas flow Initially, the exhaust gas W1 becomes highly active (high temperature) due to the first heater 5.
[0028] Next, the high-temperature exhaust gas W1 flows toward the catalyst section 4, where it is mixed with the combustion gas B1 upstream of the catalyst section 4 (in the mixing region A in Figure 1). As a result, combustion occurs, and a portion of the VOCs in the exhaust gas W1 are treated. Furthermore, the organosilicon compounds in the exhaust gas W1 are burned and some of them adhere to the cylindrical member 20. In this case, since the exhaust gas W1 is at a high temperature, the effect of efficiently decomposing the VOCs can be obtained, and the effect of reducing or decomposing the organosilicon compounds can also be obtained.
[0029] Next, the mixed gas passes through the catalyst section 4. The VOCs in the mixed gas are converted to CO by the heated oxidation catalyst 6. ２ and H ２ It is burned and decomposed along with oxygen. In this case, since the amount of organosilicon compound is reduced in the preceding stage of the catalyst section 4, the reduction in the effect of decomposing VOCs due to catalyst poison in the oxidation catalyst 6 can be suppressed.
[0030] (4) Effects According to this embodiment, an exhaust gas treatment device 1 can be obtained without increasing the overall size. Specifically, the number of catalytic treatment stages or the amount of catalyst used can be reduced. Specifically, in a conventional configuration where there is no combustion of exhaust gas W1, the number of oxidation catalysts was 2 to 4, but in the example configuration of this embodiment, the number of oxidation catalysts could be reduced to 1. Furthermore, the effect of suppressing the "reduction in the amount of oxidation catalyst processed due to the effect of catalyst poison" can also be obtained.
[0031] 2. The exhaust gas treatment device 1 according to the second embodiment of the present invention will be described using Figure 2 of the second embodiment. Figure 2 is a schematic configuration diagram of the exhaust gas treatment device according to the second embodiment of the present invention. Note that the basic configuration and basic operation of the second embodiment are the same as those of the first embodiment, so the following description will focus on the differences.
[0032] (1) The heating section exhaust gas treatment device 1A has a heating section 2A. The heating section 2A includes a porous ceramic 15A (catalyst poison reduction section) through which a number of fluid paths are arranged for the exhaust gas W1 to pass, and a first heater 16A that heats the porous ceramic 15A.
[0033] The porous ceramic 15A is provided in the cylindrical member 20 at a position where the exhaust gas W1 is heated by the first heater 16A. More specifically, the porous ceramic 15A is provided on the exhaust gas inlet 20A side of the mixing region A.
[0034] The porous ceramic 15A has, for example, a honeycomb structure in which the interior is divided into multiple cells by partition walls. The first heater 16A heats the porous ceramic 15A and the exhaust gas W1 flowing through the multiple fluid paths within the porous ceramic 15A to 700°C or higher, preferably in the range of 700 to 800°C. At this time, in the porous ceramic 15A heated by the first heater 16A, the exhaust gas W1 is indirectly heated through the multiple fluid paths within the porous ceramic 15A, so the temperature rise of the exhaust gas W1 can be made more uniform compared to when the gas is directly heated by the first heater 16A.
[0035] (2) Exhaust gas flow Initially, the exhaust gas W1 is brought to a highly active (high temperature) state by the first heater 16A. As a result, for example, by controlling the temperature of the organic silicone compound and porous ceramic 15A in the exhaust gas W1 to 700°C or higher, the surface area for adsorption is increased, and approximately 80% to 100% of the organic silicone compound is adsorbed on the surface of the porous ceramic 15A by weight. In contrast, when the organic silicone compound and porous ceramic 15A are at a temperature below 700°C, the adsorption of the organic silicone compound onto the surface of the porous ceramic 15A is reduced to approximately 10%.
[0036] Next, the high-temperature exhaust gas W1 flows toward the catalyst section 4, where it is mixed with combustion gas B1 upstream of the catalyst section 4 (in mixing region A in Figure 2). As a result, combustion occurs, and a portion of the exhaust gas W1 is treated. Specifically, VOCs are decomposed by combustion. In this case, because the exhaust gas W1 is at a high temperature, the VOCs are effectively decomposed. Furthermore, some of the organosilicon compounds are burned, and some of the organosilicon compounds at high temperatures are adsorbed onto the surface of the cylindrical body or other surfaces.
[0037] Next, the mixed gas passes through the catalyst section 4. The mixed gas is burned and decomposed into CO ２ and H ２ O by the heated oxidation catalyst 6. In this case, since the VOC is reduced in the front stage of the catalyst section 4, the decomposition amount of the VOC is reduced. Therefore, the amount of VOC processed in the catalyst section 4 is reduced.
[0038] (3) Effect According to this embodiment, the exhaust gas treatment device 1A can be obtained without increasing the overall size. Specifically, the number of catalyst treatment stages or the amount of catalyst used can be reduced. For example, in the conventional configuration, the number of oxidation catalysts was 2 to 4, but in this embodiment, the number of oxidation catalysts can be reduced to 1.
[0039] 3. Third Embodiment The exhaust gas treatment device 1 according to the third embodiment of the present invention will be described using FIG. 3. FIG. 3 is a schematic configuration diagram of the exhaust gas treatment device according to the third embodiment of the present invention. Since the basic configuration and basic operation of the third embodiment are the same as those of the first embodiment, the following description will focus on the differences.
[0040] (1) Heating section The exhaust gas treatment device 1B has a heating section 2B. The heating section 2B includes a pretreatment agent 17B (catalyst poison reduction section) through which the exhaust gas W1 passes, and a first heater 18B that heats the pretreatment agent 17B.
[0041] The pretreatment agent 17B is provided at a position where the exhaust gas W1 is heated by the first heater 18B in the cylindrical member 20. More specifically, the pretreatment agent 17B is provided on the exhaust gas inlet 20A side from the mixing region A. [[ID=
[0044] Next, the exhaust gas W1 in a high-temperature state flows toward the catalyst unit 4, and combustion gas B1 is mixed upstream of the catalyst unit 4 (in the mixing region A in FIG. 3). As a result, combustion occurs and a part of the exhaust gas W1 is treated. Specifically, VOC is decomposed by combustion. In this case, since the exhaust gas W1 is at a high temperature, the effect of decomposing VOC is high.
[0045] Next, the mixed gas passes through the catalyst unit 4. The mixed gas is burned and decomposed into CO ２ and H ２ O by the heated oxidation catalyst 6. In this case, since the content of the organosilicon compound is reduced in the previous stage of the catalyst unit 4, an effect of suppressing "reduction in the ability to decompose VOC due to catalyst poisoning" can be obtained.
[0046] (3) Effect According to the present embodiment, an exhaust gas treatment apparatus 1B can be obtained without increasing the overall size. Specifically, the number of stages of the catalytic treatment or the amount of catalyst used can be reduced. For example, conventionally, the number of oxidation catalysts was 2 to 4, but in this embodiment, the number of oxidation catalysts can be reduced to 1.
[0047] 4. Other Embodiments Although a plurality of embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications are possible without departing from the gist of the invention. In particular, the plurality of embodiments and modifications described in this specification can be arbitrarily combined as needed.
[0048] The first zone 21 and the second zone 22 may be realized by two independent gas chambers. The number of oxidation catalysts in the catalyst unit 4 may be two or more.
[0049] 1, 1A, 1B: Exhaust gas treatment apparatus 2, 2A, 2B: Heating unit 3: Combustion gas supply unit 4: Catalyst unit (first catalyst unit) 5: First heater 6: Oxidation catalyst 15A: Porous ceramic (catalyst poisoning reduction unit) 16A: First heater 17B: Pretreatment agent (catalyst poisoning reduction unit) 18B: First heater 31: First control unit 32: Second control unit A: Mixing region B1: Combustion gas W1: Exhaust gas
Claims
1. An exhaust gas treatment apparatus comprising: an exhaust gas passage section having an exhaust gas inlet and an exhaust gas outlet; a heating section provided in the exhaust gas passage section; and a first catalyst section provided in the exhaust gas passage section on the exhaust gas outlet side of the heating section, wherein the apparatus further comprises a combustion gas supply section, the combustion gas supply section being connected to the exhaust gas passage section such that the exhaust gas and the combustion gas supplied from the combustion gas supply section are mixed in a mixing region at a position in the exhaust gas passage section on the exhaust gas inlet side of the first catalyst section, and further comprising: a first control unit for controlling the flow rate of the combustion gas supplied to the mixing region; and a second control unit for controlling the amount of heat generated by the heating section.
2. The exhaust gas treatment apparatus according to claim 1, wherein the combustion gas supply unit has a flow valve, the first control unit controls the flow valve to adjust the ratio of a first component, which is a volatile organic compound contained in the exhaust gas and to be reduced by the first catalyst unit, and a second component, which is contained in the combustion gas and reduces the first component by reacting with it, to a predetermined ratio, and the heating unit has a heater, the second control unit controls the heater to raise the temperature of the exhaust gas until it reaches a reaction temperature at which the first component and the second component react in the predetermined ratio.
3. The exhaust gas treatment apparatus according to claim 2, wherein the reaction temperature is in the range of 700 to 800 degrees.
4. The exhaust gas treatment apparatus according to claim 2 or 3, wherein the heater is provided near the exhaust gas inlet of the exhaust gas passage.
5. The exhaust gas treatment apparatus according to any one of claims 2 to 4, further comprising a catalyst poison reduction unit provided in the exhaust gas passage at a position where the exhaust gas is heated by the heater.
6. The exhaust gas treatment apparatus according to claim 5, wherein the catalyst poison reduction unit is provided on the exhaust gas inlet side of the mixing region.
7. An exhaust gas treatment apparatus comprising: a heating unit for heating exhaust gas; a combustion gas supply unit for burning the exhaust gas by supplying and mixing combustion gas with the exhaust gas heated by the heating unit; and a first catalyst unit to which the mixed exhaust gas and combustion gas are supplied.
8. The exhaust gas treatment apparatus according to claim 7, further comprising a catalyst poison reduction unit provided at a position where the exhaust gas is heated by the heating unit.
9. The exhaust gas treatment apparatus according to claim 6 or 7, wherein the heating unit heats the exhaust gas to a temperature in the range of 700 to 800 degrees Celsius.
10. The exhaust gas apparatus according to any one of claims 1 to 9, wherein the exhaust gas comprises a volatile organic compound and an organosilicon compound, the combustion gas supply unit reduces the volatile organic compound by burning the exhaust gas, and the first catalyst unit has an oxidation catalyst that decomposes the volatile organic compound.
11. The exhaust gas treatment apparatus according to any one of claims 5, 6, and 8, wherein the catalyst poison reduction unit reduces the catalyst poison contained in the exhaust gas.