JP2001314732A - Catalytic deodorizing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long life catalyst used in the catalytic deodorizing device by preventing the poisoning due to catalytic poison. SOLUTION: In this catalyst type deodorizing system which removes a odor of exhaust gas and included of hydrocarbon by a catalytic device, a water washing filter device 2 for removing one part of the catalyst piston included in the exhaust gas is disposed on the preceding stage of the catalytic device 1A and, a pretreating device 1B for removing the catalyst poison remaining in the exhaust gas which flows through the water washing filter device 2 is disposed just before the inflow side of the exhaust gas of the catalytic device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalytic deodorizing system for removing a malodor based on hydrocarbon components contained in exhaust gas.

[0002]

2. Description of the Related Art In a factory or the like that discharges an exhaust gas containing a hydrocarbon component, it is necessary to remove an offensive odor based on the hydrocarbon component in the exhaust gas. For example, in an asphalt plant that produces recycled aggregate by using recycled material to which asphalt or the like peeled off from the roadbed or the like adheres, only the recycled material is heated to produce recycled aggregate, or the core material such as stone and Recycled materials are heated together to produce recycled aggregates, but hydrocarbon-based components such as aldehydes, ketones, other intermediate products, and fats contained in exhaust gas generated when the recycled materials are heated by a burner Odors were generated from the species and the like, causing "smell pollution". As a deodorizing device for removing the odor of the exhaust gas, there is a catalytic deodorizing device for oxidizing and burning the exhaust gas at 300 to 350 ° C. As the catalytic device used in the catalytic deodorizing device, for example, a honeycomb catalytic device in which a catalyst such as Pt or Pd is supported on a surface portion of a ceramic carrier formed in a honeycomb shape is used, and is included in the exhaust gas. The combustible substances are oxidized and burned by the catalyst. When the flammable substance is a hydrocarbon-based substance, harmless and odorless CO
₂ and H ₂ O.

[0003]

However, the exhaust gas contains a component called a catalyst poison, and this catalyst poison is poisoned by the catalyst of the catalyst device used in the catalytic deodorizer. In addition, there is a problem that the catalytic reaction of the catalyst device is stopped from attenuating, and the catalyst device does not function. That is, there is a problem that the life of the catalyst is shortened by the poisoning. For example, the exhaust gas discharged from the asphalt plant contains mist such as tar and oil,
Since a large amount of catalyst poisons such as dusts such as powder and sand, and silicon compounds are contained, in the above-mentioned asphalt plant, the above-mentioned catalytic deodorizing device is not used in the above-mentioned asphalt plant. 750 to exhaust gas
It uses a deodorizing device called a direct combustion system in which it is heated to 800 ° C. and burns, and fuel consumption is currently required.

[0004] The present invention has been made to solve the above-mentioned problems, and a catalytic deodorizing system capable of extending the life of a catalyst in a catalytic device for removing malodor based on hydrocarbon-based components contained in exhaust gas. For example, the present invention provides a catalytic deodorizing system that can be used in an asphalt plant that has not been used in the past due to the problem of poisoning.

[0005]

According to the present invention, there is provided a catalytic deodorizing system for removing the odor of an exhaust gas containing a hydrocarbon component using a catalytic device, the catalyst poison contained in the exhaust gas being provided upstream of the catalytic device. A washing filter device for removing a part of the catalyst device is provided, and a pretreatment agent for removing catalyst poison remaining in exhaust gas passing through the washing filter device is provided immediately before the exhaust gas inflow side of the catalyst device. Consisting of In addition, only one of the pretreatment agent and the washing filter device may be provided. Further, the washing filter device has a partition wall for partitioning an exhaust gas inflow side and an exhaust gas outflow side, and the partition wall includes a plurality of horizontal holding units to which a filter member is attached, and each of these horizontal holding units. It is preferable to use an inclined connection portion for connecting vertically, and a shower device for washing the filter member located below is provided for each inclined connection portion.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram of a catalytic deodorizing system according to the present embodiment, FIG. 2 is a cross-sectional view of a water-washing filter device provided in front of a catalytic-type deodorizing device provided with a catalytic device, and FIG. It is a partial perspective view for explanation. The catalytic deodorization system according to the present embodiment is provided, for example, as an exhaust gas treatment device for an asphalt plant to deodorize exhaust gas generated in the asphalt plant. As shown in FIG.
The catalytic deodorizing system includes a catalytic deodorizing device 1 having a catalytic device 1A, and an exhaust gas inlet 1f of the catalytic deodorizing device 1.
And a washing filter device 2 for removing mist such as tar component and oil component and dust such as sand and dust, which are part of the catalyst poison contained in the exhaust gas, and a catalytic deodorizing device 1 A pretreatment agent 1B is provided immediately before the exhaust gas inflow side of the catalyst device 1A in the inside and removes an organic silicon compound which is a catalyst poison remaining in the exhaust gas passing through the washing filter device 2.

The exhaust gas introduced into the catalytic deodorizing device 1 passes through a heat exchanger 3, a preheating chamber 4 having a burner 4a, and a blower 5, and after passing through a pretreatment agent 1B, the catalytic device 1A.
To be oxidized and burned.

[0008] As the above-mentioned catalyst device 1A, for example, P is formed on the surface of a ceramic carrier formed in a honeycomb shape.
A honeycomb catalyst device supporting a catalyst such as t or Pd is used. There are various types of catalyst devices, and any type of catalyst device can be used as long as it can remove a malodor based on hydrocarbon-based components in exhaust gas.

The washing filter device 2 includes a filter member 2A made of non-woven fabric, and a shower device 2B for washing mist and dust, which are catalyst poisons, attached to the filter member 2A with water. In detail, as shown in FIGS. 2 and 3, a partition wall 2S for partitioning the exhaust gas inflow side 2X and the exhaust gas outflow side 2Y is provided. The partition wall 2S is for mounting the filter member 2A in a horizontal state. It comprises a plurality of horizontal holding parts 2a and an inclined connecting part 2b for connecting these horizontal holding parts 2a in the vertical direction. In addition, each inclined connecting portion 2 located above the filter member 2A
b, a shower device for washing the filter member with water is provided, and the mist and dust removed from each of the filter members 2A by washing with the shower device 2B are removed from the respective inclined members located below the filter members 2A. It falls below the washing filter device 2 via the connecting portion 2b. Further, the horizontal holding portion 2a has a U-shaped filter member holding frame 2c at both ends to hold both ends of the filter member 2A. As a result, the filter members 2A are vertically dispersed and arranged in a hierarchical manner.
The filter surface can be made large, and the inflow speed of exhaust gas can be reduced. For example, about 10 m / sec is changed to 2 m / sec.
By reducing to about c, the exhaust gas passes through the filter member 2A slowly and slowly, so that the catalyst poison such as dust and mist in the exhaust gas can be sufficiently removed by the filter member 2A. Further, the water washing filter device 2 includes a pressure sensor 20 on each of the exhaust gas inflow side 2X and the exhaust gas outflow side 2Y.
When the differential pressure between X and the outflow side 2Y reaches a predetermined value, the shower device 2B releases cleaning water to clean the filter member 2A. That is, the clogging of the filter member 2A is detected by the differential pressure, and an alarm is sounded when the clogging is detected. The alarm receiver turns on the cleaning switch before or after the operation of the system, and outputs the alarm from the shower device 2B. By injecting the cleaning water, dust and mist adhering to the filter member 2A are cleaned. In the washing filter device 2, since the filter members 2A are vertically dispersed and arranged in a hierarchy, the filter surface can be enlarged, the inflow speed of the exhaust gas can be reduced, and the mist and dust are inclined at the inclined connection portion. Since it falls down efficiently via 2b, mist and dust adhering to the filter member 2A can be efficiently and sufficiently removed without adhering to the lower layer filter member 2A. In addition, 2i is an exhaust gas inlet and 2o is an exhaust gas outlet. Further, mist and dust dropped below the washing filter device 2 and discharged to the outside of the washing filter device 2 through the drain pan section 2k are collected in the sedimentation tank 2p,
Discharged outside and post-processed.

The pretreatment agent 1B is obtained by adding alumina (aluminum oxide) or the like to a ceramic structure or the like as a carrier, and removes the organic silicon compound by reacting the organic silicon compound with the alumina. .

A bag filter device 6 for removing relatively large waste dust in the exhaust gas is provided between the burner for heating the recycled material and the washing filter device 2. As shown in FIG. 4, the bag filter device 6 attaches and removes waste dust in the exhaust gas that enters through the exhaust gas inlet 6a to the plurality of cloth bag filters 6A.
Exhaust gas is discharged from the exhaust gas outlet 6b. The discharged exhaust gas is sent to the washing filter device 2.

A plurality of switching valves are provided in the exhaust gas passage between the bag filter device 6 and the washing filter device 2. Reference numeral 7A in FIG. 1 is a direct exhaust switching valve for allowing exhaust gas having no odor to be exhausted through the exhaust chimney 8 in the case of exhaust gas having no odor, such as when no recycled material is used. Reference numeral 7B denotes an exhaust gas introduction switching valve for sending exhaust gas having a bad smell generated when a recycled material is used to the washing filter device 2. 7C
Is an outside air release switching valve that does not drive out residual gas remaining in the exhaust gas flow path in the system when the system is started. That is, when the system is started, the direct exhaust switching valve 7A
To close the exhaust gas introduction switching valve 7B and the outside air release switching valve 7C
Open. When exhausting through the exhaust chimney 8, the exhaust gas introduction switching valve 7B is closed and the exhaust switching valve 7A is directly opened.
When the malodorous exhaust gas is sent to the washing filter device 2 and the catalyst deodorizing device 1, the exhaust gas switching valve 7A and the outside air release switching valve 7C are closed and the exhaust gas introduction switching valve 7B is opened.

Next, the operation will be described. The exhaust gas from the burner that heats the recycled material, as shown by the arrow in FIG.
Large dust and the like are removed by the bag filter device 6, and mist and dust, which are catalyst poisons, are removed via the washing filter device 2 and sent to the catalytic deodorizing device 1. Exhaust gas sent to the catalytic deodorizing device 1 through the washing filter device 2 is sent to the preheating chamber 4 via the heat exchanger 3 and is heated.
Then, it is sent to the pretreatment agent 1B by the blower 6. The organic silicon compound in the exhaust gas is removed by the pretreatment agent 1B and sent to the catalyst device 1A. This catalyst device 1A
Then, the exhaust gas is oxidized and burned at 300 to 350C. As a result, the odor of the exhaust gas generated from the aldehydes, ketones, other intermediate products, fats, etc. of the hydrocarbon-based components is removed, resulting in harmless and odorless CO ₂ and H ₂ O. 3 to the outside. When the pretreatment agent 1B is used at a low temperature of 300 ° C. or less, the effect is attenuated and clogging and ignition may occur.
It is desirable to use in an atmosphere of 0 ° C. or higher. For this reason, the temperature of the exhaust gas is raised to about 350 ° C. in the preheating chamber 4 and sent to the pretreatment agent 1B.

According to the catalytic deodorizing system of the present embodiment, most of the components that become catalyst poisons are removed before exhaust gas is led to the catalytic device 1A.
The life of the catalyst A can be extended. Depending on the type of catalyst poison, the poisoned catalyst can be regenerated by washing or the like. For example, it is possible to regenerate the catalyst by washing it with water in the case of dust, baking it in the case of mist, etc., and chemical cleaning in the case of organic silicon compounds, etc. Must be performed In the present embodiment, since the catalyst poison that causes poisoning can be removed in advance, a system that can reduce the maintenance work of the catalyst device 1A and prolong the life of the catalyst of the catalyst device 1A can be obtained. Therefore, since the problem of catalyst poisons can be improved, the present system can be used in an asphalt plant, and has a lower temperature (3 times) than a direct combustion type deodorizer conventionally used in an asphalt plant.
(00-350 ° C) so that the exhaust gas can be burned and deodorized.
Fuel efficiency can be greatly improved. CO ₂ C
O and NOx can be greatly reduced.

Further, since the washing filter device 2 is provided, the filter effect can be maintained for a long time, and the system according to the present embodiment using the washing filter device 2 has an effect of removing tar and mist which are catalyst poisons. The system can be maintained for a long time, the life of the catalyst of the catalyst device 1A can be prolonged, and the effect that maintenance of the catalyst device 1A can be reduced can be maintained for a long time.

Further, when the exhaust gas containing a large amount of tar is supplied to the pretreatment agent 1B, it is necessary to periodically perform "firing" at 500 ° C. for about 15 to 20 minutes in order to exert a sufficient effect. However, in the present system, since the tar component can be removed in advance by the washing filter device 2, the pretreatment agent 1B
Can be reduced, and a sufficient effect can be exhibited for a long time. That is, maintenance of the pretreatment agent 1B can be reduced, and a sufficient pretreatment effect can be exerted for a long time.

Therefore, by providing both the water washing filter device 2 and the pretreatment agent 1B, an excellent system which can prolong the life of the catalyst of the catalyst device 1A can be obtained. In particular, a catalytic deodorizing system suitable for exhaust gas treatment of an asphalt plant can be obtained.

Further, since the bag filter device 6 is provided, dust containing catalyst poison can be reliably removed, and the life of the catalyst of the catalyst device 1A can be extended.

The exhaust gas of the catalytic deodorizing device 1 shown in FIG. 1 may be used for preheating a burner for heating the recycled material.

Further, in the above embodiment, the case where the present invention is applied to an asphalt plant has been described. However, the system of the present invention can be applied to all cases where it is necessary to remove the odor of exhaust gas containing hydrocarbon-based components. For example, the present system can be applied to a chemical factory, an offset printing factory, a metal printing factory, a paint drying factory, and the like, because exhaust gas containing hydrocarbon-based components is generated.

Further, in the above embodiment, the system provided with both the washing filter device 2 and the pretreatment agent 1B has been described, but only one of them may be provided according to the type of the catalyst poison. For example, if exhaust gas containing a small amount of components such as mist and dust is to be treated, the washing filter device need not be provided, and components such as mist and dust are large.
If the exhaust gas containing a small amount of the organic silicon compound is to be treated, the pretreatment agent need not be provided.

In the case of removing other catalyst poisons such as organic phosphorus compounds and organometallic compounds, a pretreatment agent which easily reacts with these catalyst poisons may be used.

[0023]

According to the present invention, there is provided a catalytic deodorizing system capable of extending the life of the catalyst of the catalytic device and reducing the trouble of maintenance of the catalytic device. Therefore, for example, it can be used in an asphalt plant, and can greatly improve fuel efficiency as compared with a direct combustion type deodorizing device used in a conventional asphalt plant. Also, by providing a washing filter device, tar content,
A catalytic deodorization system suitable for exhaust gas treatment of an asphalt plant that emits exhaust gas containing a large amount of mist such as oil can be obtained. In addition, it has a partition wall for partitioning an exhaust gas inflow side and an exhaust gas outflow side, and this partition wall is used for connecting a plurality of horizontal holding parts to which a filter member is attached and these horizontal holding parts in a vertical direction. With the inclined connecting portion, each inclined connecting portion is provided with a shower device for washing the filter member located below, the filter members are vertically dispersed, arranged in a hierarchical manner, the filter surface can be enlarged, By using a flush filter device that can reduce the inflow speed of the exhaust gas, mist and dust in the exhaust gas can be efficiently and sufficiently removed.

[Brief description of the drawings]

FIG. 1 is a block diagram of a catalytic deodorizing system according to an embodiment of the present invention.

FIG. 2 is a sectional view of a washing filter device.

FIG. 3 is a partial perspective view for explaining the structure of a washing filter device.

FIG. 4 is a perspective view showing a bag filter device.

[Explanation of symbols]

1. Catalytic deodorizing device, 1A catalytic device, 1B pretreatment agent, 2 washing filter device.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenji Kubota 2-19-8 Momoi, Suginami-ku, Tokyo Railway Car Industry Co., Ltd. (72) Inventor Seiichi Kashihara 2-19-8 Momoi, Suginami-ku, Tokyo No. Inside the Railway Vehicle Industry Co., Ltd. (72) Inventor Isao Sonobe 8-27 Shin-Ogawa-cho, Shinjuku-ku, Tokyo Inside Guyart Kumagai (72) Inventor Hideyuki Tokioka 8-27, Shin-Ogawa-cho, Shinjuku-ku, Tokyo F-term (reference) in Guy Art Kumagai Corporation 4D032 AB03 AB09 AC01 BB05 4D048 AA17 AA18 AA19 AA20 AA22 AA23 AA24 AB01 AB03 AB05 AB06 BA30Y BA31Y BB02 BC04 CA03 CC38 CC39 CD02 CD05 CD08

Claims (4)

[Claims] 1. A catalytic deodorizing system for removing an odor of an exhaust gas containing a hydrocarbon component by a catalyst device, wherein a catalyst poison contained in the exhaust gas is partially removed before the catalyst device. A catalytic filter, comprising a washing filter device and a pretreatment agent for removing catalyst poison remaining in exhaust gas passing through the washing filter device, immediately before the exhaust gas inflow side of the catalyst device. Deodorizing system. 2. A catalytic deodorizing system for removing an odor of an exhaust gas containing a hydrocarbon component using a catalytic device, wherein a pretreatment agent for removing a catalyst poison contained in the exhaust gas is provided upstream of the catalytic device. Catalytic deodorization system characterized by having provided. 3. A catalytic deodorizing system for removing an odor of an exhaust gas containing a hydrocarbon component by a catalytic device, wherein a washing filter device for removing a catalyst poison contained in the exhaust gas is provided upstream of the catalytic device. Catalytic deodorization system characterized by having provided. 4. The washing filter device has a partition wall for partitioning an exhaust gas inflow side and an exhaust gas outflow side, the partition wall includes a plurality of horizontal holding portions to which a filter member is attached, and each of these horizontal holding portions. And an inclined connecting part for connecting the parts in a vertical direction, and each inclined connecting part is provided with a shower device for rinsing the filter member located therebelow. Item 4. A catalytic deodorizing system according to Item 3.