JP5075470B2 - Catalytic combustion reactor for organic exhaust gas - Google Patents

Description

  The present invention relates to a catalytic combustion reactor for detoxifying an organic substance-containing exhaust gas discharged from a factory or the like by catalytic combustion treatment.

  For example, organic matter-containing exhaust gas (hereinafter simply referred to as exhaust gas) discharged from a factory having acrylic acid and methacrylic acid production facilities needs to be rendered harmless. As exhaust gas, in addition to what is discharged through piping from processes such as chemical factories, gas containing organic matter leaked from the process is covered with air in the building while the process is covered with buildings such as painting factories. Including those collected by suction.

  In order to detoxify such exhaust gas, for example, when the concentration of organic substances in the exhaust gas is several hundred ppm or more, it is certain that the exhaust gas is burnt and is economical. As a method for the combustion treatment, a direct combustion method in which auxiliary fuel is burned as necessary and directly combusted in a combustion furnace at a high temperature of 800 ° C. or higher, and an organic substance concentration is adjusted within a predetermined range in the catalyst layer. There is a catalytic combustion method in which combustion is performed at a relatively low temperature of 700 ° C. or lower.

  In Patent Document 1, as a direct combustion method, when exhaust gas is burned in a combustion furnace, adhesion of combustion products to the furnace wall is prevented, and low concentration combustible harmful components contained in the exhaust gas are efficiently burned. An exhaust gas combustion method and apparatus that can be produced is shown. The method of directly combusting exhaust gas in a combustion furnace has the advantage that stable processability can be obtained without complicated operations, but it also has problems. In the exhaust gas direct combustion method, since it is necessary to perform combustion at a high temperature (at least 800 ° C. or more), a lot of energy is required. For this reason, a large amount of auxiliary fuel is required, and costs for combustion equipment, exhaust heat recovery equipment, exhaust gas treatment equipment, and the like are required. Furthermore, generation of dioxins, NOx, etc., generation of global warming gas accompanying a large amount of energy consumption, etc. are also problems. Therefore, except when a large amount of diluent gas is required or when it is not suitable for catalytic combustion that contains a large amount of components that are harmful to the catalyst, exhaust gas with a high concentration of organic matter is more effective than direct combustion in a combustion furnace. It is advantageous to burn.

  The catalytic combustion method can complete the combustion reaction at a lower temperature (700 ° C. or lower) than the direct combustion method, and does not require auxiliary fuel. Therefore, the combustion facility and the exhaust heat recovery facility are relatively small, and Exhaust gas treatment equipment is not required. Moreover, it can be said to be a method that is friendly to the earth, such as generation of dioxin and NOx is extremely small, and energy consumption is also small, so that the generation amount of global warming gas is small.

The catalytic combustion method minimizes the amount of heat loss to the outside during catalytic combustion reaction, the location where the burned reaction fluid contacts the outer surface of the reactor, and the use of high-grade materials with heat resistance and corrosion resistance. A catalytic combustion reactor having a limit structure and a catalyst structure are disclosed (Patent Document 2). Patent Document 2 discloses a catalytic combustion reaction method using these catalytic combustion reactors and a catalyst structure.
Although catalytic combustion of exhaust gas is a low temperature compared with direct combustion, it is a reaction accompanied by large heat generation, and the catalyst layer greatly expands and contracts as combustion starts and stops. Further, a temperature difference of several hundred degrees is generated between the gas inflow surface and the gas outflow surface of the catalyst layer, and the magnitudes of thermal expansion and contraction are completely different. Furthermore, since the material and shape of the support located on the gas inflow surface and gas outflow surface of the catalyst layer and the catalyst filling portion are completely different, the degree of thermal expansion / contraction is completely different. Therefore, in a somewhat large reactor, the catalyst layer has a structure in which stress due to thermal expansion / contraction is not concentrated, and the difference in thermal expansion / contraction between the support of the catalyst layer and the catalyst portion causes gas to enter the catalyst layer. It is important to have a structure that does not cause gaps that cause blow-through. However, Patent Document 2 does not have sufficient countermeasures against this problem.

Further, as a catalytic reactor for treating nitrogen oxides in exhaust gas by the catalytic reduction method, a rectangular catalyst packed layer in which a gas inflow surface and a gas outflow surface are formed of a metal mesh or a perforated plate in a gas flow path, A solid-gas contact reaction apparatus characterized by being arranged in combination with each other so as to open a skirt in the gas inflow direction is disclosed (Patent Document 3). However, since this apparatus is intended for the reduction reaction of nitrogen oxides in exhaust gas, there is no heat generated by the reaction, and no measures are taken against the above-described thermal expansion / contraction.
As described above, as a reactor that performs catalytic combustion of exhaust gas with a large amount of heat generation, a reactor that maintains high purification performance of exhaust gas and can continue stably even if there is large thermal expansion / contraction is desired.
JP-A-6-129627 JP 2004-28556 A JP 51-126976 A

In the case of the catalytic combustion reaction for purifying the exhaust gas as described above, the intended purpose cannot be achieved economically unless the exhaust gas purification performance is kept high and at the same time stable.
That is, (1) the residence time of the exhaust gas in the catalyst layer is uniform, (2) the temperature of the support of the catalyst layer changes rapidly, and a large temperature gradient between the gas inflow surface and the gas outflow surface of the catalyst layer (3) A structure that does not cause gaps in the catalyst layer due to thermal expansion / contraction between the catalyst layer support and the catalyst filling portion. Etc. are necessary. When the scale of the catalytic combustion reactor exceeds a certain scale, the importance of being able to continue stably increases.

  In the present invention, when an organic matter-containing exhaust gas is rendered innocuous by catalytic combustion, an organic matter-containing exhaust gas catalytic combustion reactor excellent in economic efficiency that can maintain high purification performance of the organic matter-containing exhaust gas and at the same time can be stably provided. With the goal.

In the present invention, the inside of the outer shell container, the partition wall is fixed with a partition wall opening, the hollow cylindrical body is provided, et al is rising from the periphery of the partition wall opening,
The hollow columnar body is formed by a plurality of plate-like catalyst layers rising so as to surround the partition opening,
The upper part of the hollow columnar body is closed by an upper lid of the catalyst layer, the inside of the outer shell container is partitioned by the partition wall, the hollow columnar body, and the upper lid of the catalyst layer, and gas is supplied to one side of the partitioned outer shell container. There is a gas outlet on the other side,
Each of the plurality of plate-like catalyst layers is
A support body that rises so as to surround the partition wall opening and through which the exhaust gas forming the gas inflow surface can pass ; and a support body through which the exhaust gas that forms the gas outflow surface can pass ;
Two side walls that rise from the partition wall and do not allow exhaust gas to pass through;
A catalyst-filled portion comprising a catalyst filled in a space formed by the two supports and the two side walls;
On the two side walls, a support holding groove that fits the two supports and holds them at a certain distance is formed along a direction in which the two side walls rise from the partition wall,
Said gas inlet surface gas for forming a can pass support and can pass the exhaust gas to form the gas outlet side support is fitted to the support retaining groove, portions other than the support of the catalyst layer and the partition wall is not fixed to the can stretch independently with the support retaining groove in,
The inclination angle of the catalyst layer with respect to the vertical direction is 45 ° or less,
Provided is a catalytic combustion reactor for organic substance-containing exhaust gas in which gas that has entered the outer shell container from the gas inlet passes through the catalyst filling portion of the catalyst layer and is discharged from the gas outlet .

In the catalytic combustion reactor for organic matter-containing exhaust gas of the present invention, it is preferable that the support forming at least the gas outflow surface has a closed plate shape in which 3% to 20% of the support has no opening.
Moreover, it is preferable to use the catalytic combustion reactor of the organic substance containing exhaust gas of this invention for the catalytic combustion of the organic substance containing exhaust gas whose combustion temperature is 100-700 degreeC.

  According to the catalytic combustion reactor for organic matter-containing exhaust gas of the present invention, for example, when the organic matter-containing exhaust gas discharged from a factory or the like is made to be harmless by catalytic combustion treatment, the exhaust gas purification performance can be kept high. Can achieve the intended purpose.

Hereinafter, an embodiment of an organic substance-containing exhaust gas catalytic combustion reactor (hereinafter sometimes referred to as a reactor) according to the present invention will be described with reference to FIGS.
As shown in FIG. 1, in the catalytic combustion reactor 1, a partition wall 20 that does not allow exhaust gas to pass is fixed inside an outer shell container 10. The partition wall 20 is provided with a partition wall opening 21.
Further, in the reactor 1 of this embodiment example, a gas inlet 11 is provided in the upper part and a gas outlet 12 is provided in the lower part.

  As shown in FIGS. 4 and 5, a hollow columnar body 40 that rises vertically from the peripheral edge of the partition wall opening 21 is provided on the partition wall 20, and a catalyst layer 30 is formed on the hollow columnar body 40. . In the present embodiment example, as shown in FIG. 4, eight catalyst layers 30 are connected in a prismatic shape to form a hollow columnar body 40.

As shown in FIG. 5, the catalyst layer 30 is provided with side walls 22 that do not allow exhaust gas to pass therethrough, and support body holding grooves 23 and 24 are formed in the side walls 22.
Further, the catalyst layer 30 includes a support 31 (hereinafter referred to as the support 31) that forms a gas inflow surface and a support 32 (hereinafter referred to as a support 32) that forms a gas outflow surface. 22 are respectively fitted in the support holding grooves 23 and 24 formed so that the gas inflow surface and the gas outflow surface are always at a constant distance. Further, the catalyst layer 30 is filled with catalyst particles in a space formed by the two side walls 22 and the supports 31 and 32.
As described above, the hollow columnar body 40 has the support body holding grooves 23 and 24, and the support body holding grooves 23 and 24 are used so that the distance between the opposite side surfaces of the hollow columnar body 40 is a constant distance. 31 and a support 32 are disposed, and a catalyst is filled between the supports 31 and 32 to form the catalyst layer 30.
In the present embodiment, the supports 31 and 32 are provided vertically on the partition wall 20 as shown in FIG. The upper end surface of the catalyst layer 30 is closed by a catalyst layer upper lid 42.
Further, the supports 31 and 32 are only fitted into the support holding grooves 23 and 24, and are not fixed to the partition wall 20 and the catalyst layer upper lid 42. Therefore, in the reactor 1, the support 31 and the support 32 can be expanded and contracted independently.

In the reactor 1 of the present invention, as described above, the hollow columnar body 40 is formed with a set of eight catalyst layers 30 connected in a prismatic shape. The upper opening 41 of the hollow columnar body 40 is closed by the seal plate 43 (FIG. 1), and the exhaust gas that has passed through the catalyst layer 30 from the support 31 side flows into the reactor upper part 13 from the upper opening, The exhaust gas entering from the inflow port 11 is prevented from flowing into the hollow columnar body 40 without passing through the catalyst layer 30.
The number of catalyst layers 30 formed on the side surface of one hollow columnar body 40 is not limited to eight. For example, six or ten catalyst layers 30 may be connected in a prismatic shape, or may have a structure in which only one catalyst layer 30 is provided and all other portions are sidewalls through which exhaust gas does not pass.
The number of hollow columnar bodies 40 is not limited, and a plurality of hollow columnar bodies 40 can be provided in the reactor 1 (four in FIG. 4). For example, the number may be three or five. The number of catalyst layers 30 formed on the side surfaces of the hollow columnar body 40 and the hollow columnar body 40 is the most appropriate number based on the required catalyst amount, the catalyst layer thickness, the gas passage area, etc. determined from the amount of exhaust gas for performing catalytic combustion treatment. It may be determined by calculation.

  The exhaust gas inflow surface and the exhaust gas outflow surface of the supports 31 and 32 are formed by, for example, a metal net or a perforated plate. In the support 32, a region of 3 to 20% from the upper end of the support 32 is a closed plate-like support upper portion 34 that has no opening and does not pass exhaust gas, and only the portion of the support opening surface 36 is present. A gas outflow surface should be formed (FIGS. 2 and 3). Alternatively, the support 31 may be provided with a similar support plate-like support upper portion 33 so that only the support opening surface 35 forms a gas inflow surface. The support 31 and the support 32 have a shape in which a bar 38 is attached to a rectangular frame 37 and a wire mesh 39 is stretched, and these are fitted into the support holding groove 23 and the support holding groove 24 of the side wall 22, respectively. . Note that the upper part of the support in the shape of a closing plate may be provided only on the support 31.

  As described above, in the reactor 1, the partition wall 20 having the partition wall opening 21 is fixed inside the outer shell container 10, and the partition wall 20 is provided with the hollow columnar body 40 rising from the peripheral edge of the partition wall opening 21. The upper opening 41 of the hollow columnar body 40 is closed to partition the outer shell container 10. Further, since the catalyst layer 30 is formed on the side surface of the hollow columnar body 40, the exhaust gas flowing into the reactor upper part 13 from the gas inlet 11 flows out of the gas from the support 31 side forming the gas inlet surface. It passes through the catalyst layer 30 toward the support 32 forming the surface, enters the reactor lower part 14 through the partition opening 21, and is discharged from the gas outlet 12.

  For example, when the exhaust gas from a factory or the like is made to be harmless by catalytic combustion treatment, the catalytic combustion reactor is required to have a high purification rate (reaction rate) so that the organic matter concentration in the exhaust gas after treatment is at least 1 ppm or less. . In order to obtain such a high purification rate, the time during which the exhaust gas stays in the catalyst layer must be made uniform. If the residence time is not uniform, even if the average residence time is a predetermined value, the purification rate of the exhaust gas passing through the portion where the residence time is short is lowered, and the overall purification rate is lowered. Further, since the gas flow resistance is generally small in the portion where the residence time is short, a large amount of exhaust gas selectively flows into the portion, and the reduction in the overall purification rate is accelerated. In order to make the residence time uniform, it is important that the catalyst layer 30 is formed so that the thickness a of the catalyst filling portion 50 is uniform, that is, the distance a between the support 31 and the support 32 is constant. It is.

  Moreover, it is preferable that the thickness a (distance a between the support 31 and the support 32) of the catalyst-filled portion 50 is in the range as shown below. If the thickness a is equal to or greater than the lower limit value, the pressure loss ΔP when the exhaust gas passes through the catalyst layer 30 is not extremely reduced, and it is difficult for the exhaust gas to drift or blow through, and a uniform flow rate (extruded flow) is obtained. It is done. The lower limit value of the thickness a is considered to be at least several tens of times the catalyst particle diameter, although it depends on the flow rate of the exhaust gas flowing into the reactor 1 and the shape and particle diameter of the catalyst. On the other hand, if the thickness a is equal to or less than the upper limit value, the pressure loss ΔP of the exhaust gas passing through the catalyst layer 30 does not become too large, and a large amount of power is not required to send the exhaust gas. In this case, the equipment cost and the operation cost can be suppressed, and the economy is excellent. The upper limit value of the thickness a is determined by the flow rate of the exhaust gas flowing into the reactor 1, the shape of the catalyst, the particle diameter, and the like.

  In catalytic combustion of exhaust gas, although there are some differences depending on the type and concentration of combustibles in the exhaust gas and the type of catalyst, it is usually preferable to adjust the combustion temperature in the range of 100 to 700 ° C. When the exhaust gas temperature entering the catalyst layer 30 is lower than the ignition temperature, the combustion reaction of the combustible material in the exhaust gas does not occur. Therefore, the exhaust gas needs to be preheated to an ignition temperature or higher and supplied to the catalyst layer 30, and the temperature is at least 100 ° C. or higher although it varies depending on the type of combustible material. Moreover, although the temperature of the exhaust gas supplied to the catalyst layer 30 further increases due to the combustion reaction, it is preferable that the combustion temperature does not exceed 700 ° C. even if the organic matter in the exhaust gas is completely combusted. This is because it is necessary to keep the combustion temperature lower than the temperature at which the thermal degradation of the catalyst proceeds in order to maintain a stable purification rate in the long term. The upper temperature limit varies depending on the type of catalyst and the like because the thermal deterioration temperature differs, but the temperature is 700 ° C. or less for most catalysts. However, in order to obtain a high purification rate, the combustion temperature of the exhaust gas should be high. Therefore, it is desirable that the combustion temperature be as high as possible within a range lower than the temperature at which the thermal degradation of the catalyst proceeds.

  As described above, in the catalytic combustion of exhaust gas, the combustion temperature of exhaust gas is 100 ° C. or more on the gas inflow surface (support 31) of the catalyst layer 30 and 700 ° C. or less on the gas outflow surface (support 32) of the catalyst layer 30. It is good to control so that it becomes. The temperature of the gas outflow surface of the catalyst layer 30 is controlled by diluting and adjusting the combustible concentration in the exhaust gas with air or the like so that the adiabatic temperature rise of the exhaust gas due to combustion is within a predetermined range.

In the catalytic combustion reaction, as described above, the temperature of the catalyst layer 30 is considerably higher than the normal temperature. On the other hand, since the heat capacity of the catalyst layer 30 is relatively small, the temperature rises rapidly when the combustion reaction starts, and conversely, the temperature drops rapidly when there is no combustible material. Even if the combustion reaction is in a steady state, a large temperature difference occurs between the gas inflow surface (support 31) and the gas outflow surface (support 32) of the catalyst layer 30. Therefore, in the structural design of the supports 31 and 32 of the catalyst layer 30, special consideration is necessary so that there is no concentration of stress accompanying expansion and contraction of the material due to heat. For example, the support bodies 31 and 32 may be fitted into the support body holding grooves 23 and 24 so as not to be fixed to the partition wall 20 and the catalyst layer upper lid 42 as in this embodiment. If it does in this way, the support bodies 31 and 32 will not mutually restrain, but a mutual support body can be thermally expanded / contracted independently. In addition, by doing this, the support bodies 31 and 32 can slide freely in the support body holding grooves 23 and 24 and freely expand and contract in accordance with heat. Therefore, even if the catalyst layer 30 undergoes thermal expansion / contraction, the stress concentration of the catalyst layer 30 can be avoided and a stable combustion reaction can be performed.
As the shape of the catalyst layer, a rectangular parallelepiped catalyst layer 30 as shown in this embodiment or a hollow columnar body 40 obtained by combining some of them is preferable.

In this embodiment, the support bodies 31 and 32 have a support plate upper part 33 and 34 in a region of 3 to 20% from the upper end of the support body. Therefore, the exhaust gas can pass through the support bodies 31 and 32 only at the portions of the support opening surfaces 35 and 36. This is because the exhaust gas flowing into the catalyst layer 30 from the support 31 is allowed to pass through the catalyst filling portion 50 at least by the distance a.
That is, it is for preventing the short circuit of the exhaust gas in the upper part of the catalyst layer 30. The catalyst filling portion 50 is an aggregate of small catalyst particles. Therefore, the catalyst filling portion 50 inside the catalyst layer 30 and the supports 31 and 32 are completely different in material and shape, so that the degree of thermal expansion / contraction is greatly different. If the region of the upper plate 34 in the form of a closing plate is 3% or more from the upper end of the support 32, the upper end surface 51 of the catalyst filling portion 50 is always the portion of the upper support 34 even if thermal expansion / contraction occurs. The catalyst layer 30 is in a state in which the catalyst is surely filled up to the portion of the support opening surface 36 into which the exhaust gas flows. Therefore, the distance a is always guaranteed for the exhaust gas to pass through the catalyst filling portion 50. Further, if the area of the upper support 34 in the shape of a closing plate is 20% or less from the upper end of the support 32, the flow rate of the exhaust gas can be increased and the exhaust gas can be purified with high efficiency. As described above, at least the support 32 is provided with the closing plate-like support upper portion 34, so that the portion of the catalyst filling portion 50 in the region of the support upper portion 34 is replaced with the supports 31 and 32 and the catalyst filling portion. The adjustment allowance for the difference in thermal expansion / contraction from 50 is possible.

Next, another embodiment of the catalytic combustion reactor for organic substance-containing exhaust gas of the present invention will be described with reference to FIGS.
As shown in FIG. 6, in the catalytic combustion reactor 2 (hereinafter referred to as the reactor 2), a partition wall 70 that does not allow exhaust gas to pass is fixed inside the outer shell container 60. The partition wall 70 is provided with a partition wall opening 71.
Further, the reactor 2 is provided with a gas inlet 61 at the upper part and a gas outlet 62 at the lower part.

In the reactor 2, similarly to the reactor 1, a hollow columnar body 90 is provided on the peripheral edge of the partition wall opening 71, and a catalyst layer 80 is formed on the hollow columnar body 90.
As in the case of the reactor 1, the catalyst layer 80 includes a support body 81 (hereinafter referred to as a support body 81) that forms a gas inflow surface and a support body 82 (hereinafter referred to as a support body 82) that forms a gas outflow surface. Are formed at a constant distance and filled with a catalyst (FIG. 7). The supports 81 and 82 are provided on the partition wall 70 so as to be inclined, and the catalyst layer 80 is inclined. The inclination angles α and β formed by the catalyst layer 80 and the vertical direction are both 45 ° or less. Further, the inclination angles α and β may be different.
The hollow columnar body 90 abuts two inclined catalyst layers 80, the side surface portion (side surface 93) is a wall body that does not allow exhaust gas to pass through, and the upper end surface of the catalyst layer 80 is closed by the catalyst layer upper lid 91. The upper part is closed with a seal plate 92. Therefore, the gas that has passed through the catalyst layer 80 does not flow into the reactor upper part 63, and the exhaust gas that has entered from the gas inlet 61 does not flow into the hollow columnar body 90 without passing through the catalyst layer 80.
Similarly to the reactor 1, the supports 81 and 82 are fitted into support holding grooves provided on the side wall 72 and are not fixed to the partition wall 70 and the catalyst layer upper lid 91.

  A plurality of the hollow columnar bodies 90 are arranged on the partition wall 70 (three in FIG. 6). The number of the hollow columnar bodies 90 is not particularly limited. As in the case of the reactor 1, the most appropriate number is calculated from the required catalyst amount determined from the amount of exhaust gas to be burned, the thickness of the catalyst layer, the gas passage area, and the like. Just decide.

As in the case of the reactor 1, the support 81 and the support 82 form a gas inflow surface and a gas outflow surface by a metal mesh, a perforated plate, or the like. The support 82 is provided with a closed plate-like support upper portion 84 having no opening in an area of 3 to 20% from the upper end of the support 82, and only the portion of the support opening surface 86 becomes a gas outflow surface. Good (Fig. 7). Further, the support member 81 may be provided with a similar support plate-like support upper portion 83 so that only the support opening surface 85 becomes a gas inflow surface. The portion on the closing plate may be provided only on the support 81.
The support 81 and the support 82 have a shape in which a crosspiece 88 is attached to a frame 87 and a wire mesh 89 is stretched in the same manner as in the reactor 1, and are inclined by being fitted in support support grooves provided on the side walls 72. To be provided.

  As described above, in the reactor 2, as in the reactor 1, the outer shell container 60 is partitioned, and the gas that flows from the gas inlet 61 to the reactor upper part 63 forms a gas inflow surface. It passes through the catalyst layer 80 from the body 81 side to the support 82 side forming the gas outflow surface, enters the reactor lower part 64 through the partition wall opening 71, and is discharged from the gas outlet 62.

  The thickness b (distance b between the support 81 and the support 82) of the catalyst-packed portion 100 is preferably in the same range as the thickness a of the reactor 1. If the thickness b is equal to or greater than the lower limit value, the pressure loss ΔP when the exhaust gas passes through the catalyst layer 80 is not extremely reduced, and the exhaust gas is less likely to be knitted or blown out, resulting in a uniform flow rate (extrusion flow). can get. On the other hand, if the thickness b is less than or equal to the upper limit value, the pressure loss ΔP of the exhaust gas passing through the catalyst layer 80 does not become too large, and no large power is required to send the exhaust gas. It can be suppressed and is economical.

In the reactor 2, similarly to the reactor 1, in order to prevent a short circuit of exhaust gas at the upper part of the catalyst layer 80, a support upper part 84 on the closing plate is provided in a region of 3 to 20% from the upper end of the support 82. ing. Since the supports 81 and 82 and the catalyst-filled portion 100 are completely different in material and shape, the degree of thermal expansion / contraction is greatly different.
If the region of the upper end plate-like support 84 is 3% or more from the upper end of the support 82, the upper end portions 83, 84 of the upper end surface 101 of the catalyst filling portion 100 are always expanded and contracted even if the upper end surface 101 is thermally expanded / contracted. In other words, the portions of the support opening surfaces 85 and 86 into which the exhaust gas from the catalyst layer 80 flows are always filled with the catalyst. Therefore, the distance b is ensured for the exhaust gas to pass through the catalyst-filled portion 100. Moreover, if the area | region of the support plate upper part 84 of a closing plate shape is 20% or less from the upper end of the support body 82, the flow volume of waste gas can be increased and combustion can be performed with high efficiency. As described above, at least the support 82 is provided with the closing plate-like support upper portion 84 so that the portions of the catalyst filling portion 100 in the region of the support upper portion 84 are separated from the supports 81 and 82 and the catalyst filling portion 100. The adjustment allowance for the difference in thermal expansion / contraction with

 In addition, since the catalyst layer 30 is provided vertically in the reactor 1, even if the supports 31 and 32 and the catalyst filling portion 50 expand and contract at different expansion rates, the catalyst particles appropriately have gaps due to the influence of gravity. Move to fill. Therefore, the portions of the support opening surfaces 35 and 36 of the catalyst layer 30 are kept filled with the catalyst particles, and the thickness of the catalyst filling portion through which the exhaust gas passes is kept uniform. In the reactor 2, since the catalyst layer 80 is provided with an inclination, the inclination angles α and β must be set to 45 ° or less in order to obtain the effect of gravity as described above.

As mentioned above, although two example embodiments were described about the catalyst combustion reactor of the organic substance containing exhaust gas of the present invention, the embodiment is not limited to these two. For example, instead of the hollow columnar body 40 in which the rectangular parallelepiped catalyst layers 30 are connected, a catalyst layer having a shape like a concentric cylinder may be provided. Alternatively, the gas inlet and the gas outlet, and the support 31 and the support 32 may be interchanged so that the exhaust gas flows from the lower side to the upper side of the reactor (the same applies to the reactor 2). The type and shape of the catalyst used in the catalytic combustion reactor of the present invention are not particularly limited as long as it is used for a normal catalytic combustion reaction. For example, a catalyst such as Pt or Pd can be used if it is an exhaust gas containing an organic substance such as styrene or acetic acid.
Further, the organic substance-containing exhaust gas treated in the catalytic combustion reactor of the present invention is not particularly limited as long as it contains a combustible organic compound. For example, methacrolein is obtained by gas phase oxidation of isobutylene or tertiary butyl alcohol. Or the exhaust gas produced | generated when manufacturing methacrylic acid and the waste gas produced | generated when vapor-phase-oxidizing propylene and producing methacrolein or methacrylic acid are mentioned. Such exhaust gas contains isobutylene, propylene, carbon monoxide, acetic acid, methacrylic acid, acrylic acid and the like as combustible organic compounds.

  According to the catalytic combustion reactor of the present invention, for example, when an organic matter-containing exhaust gas from a factory or the like is subjected to catalytic combustion treatment to be detoxified, the purification performance can be kept high, so that it is economically superior. In addition, the catalytic combustion method can complete the combustion reaction at a lower temperature than the direct combustion method, so that it does not require an auxiliary fuel and is low in energy consumption and economical. In addition, since there is no generation of dioxin or NOx and the generation amount of global warming gas is small, the method is friendly to the earth. The catalytic combustion reactor of the present invention has a great effect in performing the catalytic combustion treatment of the organic substance-containing exhaust gas more economically, and it seems that the spread of the catalytic combustion method is promoted.

1 is a longitudinal sectional view of a catalytic combustion reactor 1 that is an embodiment of the present invention. It is a detailed longitudinal cross-sectional view of the catalyst layer 30 part of FIG. It is the front view seen from the support body 32 side of the catalyst layer 30 of this invention. 1 is a cross-sectional view of a catalytic combustion reactor 1 that is an embodiment of the present invention. It is a detailed cross-sectional view of the catalyst layer 30 part of FIG. It is a longitudinal cross-sectional view of the catalytic combustion reactor 2 which is the other embodiment of this invention. It is a detailed longitudinal cross-sectional view of the hollow columnar body 90 part of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Catalytic combustion reactor 2 Catalytic combustion reactor 10 Outer shell container 11 Gas inlet 12 Gas outlet 20 Partition wall 21 Partition opening 30 Catalyst layer 31 Support body which forms gas inflow surface 32 Support body which forms gas outflow surface 40 Hollow columnar body 60 outer shell container 70 partition wall 71 partition wall opening 80 catalyst layer 81 support body forming gas inflow surface 82 support body forming gas outflow surface 90 hollow columnar body

Claims (3)

Inside the outer shell container, the partition wall is fixed with a partition wall opening, the hollow cylindrical body is provided, et al is rising from the periphery of the partition wall opening,
The hollow columnar body is formed by a plurality of plate-like catalyst layers rising so as to surround the partition opening,
The upper part of the hollow columnar body is closed by an upper lid of the catalyst layer, the inside of the outer shell container is partitioned by the partition wall, the hollow columnar body, and the upper lid of the catalyst layer, and gas is supplied to one side of the partitioned outer shell container. There is a gas outlet on the other side,
Each of the plurality of plate-like catalyst layers is
A support body that rises so as to surround the partition wall opening and through which the exhaust gas forming the gas inflow surface can pass ; and a support body through which the exhaust gas that forms the gas outflow surface can pass ;
Two side walls that rise from the partition wall and do not allow exhaust gas to pass through;
A catalyst-filled portion comprising a catalyst filled in a space formed by the two supports and the two side walls;
On the two side walls, a support holding groove that fits the two supports and holds them at a certain distance is formed along a direction in which the two side walls rise from the partition wall,
Said gas inlet surface gas for forming a can pass support and can pass the exhaust gas to form the gas outlet side support is fitted to the support retaining groove, portions other than the support of the catalyst layer and the partition wall is not fixed to the can stretch independently with the support retaining groove in,
The inclination angle of the catalyst layer with respect to the vertical direction is 45 ° or less,
A catalyst combustion reactor for organic substance-containing exhaust gas in which gas entering the outer shell container from the gas inlet passes through the catalyst filling portion of the catalyst layer and is discharged from the gas outlet .   2. The catalytic combustion reactor for exhaust gas containing organic matter according to claim 1, wherein the support forming at least the gas outflow surface is a closed plate shape having no opening in an area of 3 to 20% from the upper end of the support.   The catalytic combustion reactor for organic matter-containing exhaust gas according to claim 1 or 2, which is used for catalytic combustion of an organic matter-containing exhaust gas having a combustion temperature of 100 to 700 ° C.

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