Exhaust gas treatment device

Abstract

To provide an exhaust gas treatment device which can disperse exhaust gas uniformly.SOLUTION: A denitrification plant 3 is an exhaust gas treatment device used for exhaust gas containing NOx such as N2O. A cylindrical body having an inlet 3a and an outlet 3b for the exhaust gas has a first area 51 and a second area 53 in a written order from the inlet 3a side. The second area 53 is provided with: a second discharge part 531 for discharging a reductant agent; a first plate part 533 at the downstream side of the second discharge part 531; a second plate part 535 at the downstream side of the first plate part 533; and a second catalyst part 537 at the downstream side of the second plate part 535. In the first plate part 533 and the second plate part 535, first openings 533a are formed at both ends in a first direction which is orthogonal to a center axis 59 of the second area 53 and a center axis 59 of the first plate part 533. The second plate part 535 has a second opening 535a smaller than the first plate part 533 between the first openings 533a at both sides in the first direction.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an exhaust gas treatment device used for exhaust gas emitted from an internal combustion engine that uses ammonia as fuel or as part of the fuel. [Background technology]

[0002] As an apparatus for treating exhaust gas containing NOx such as NO, NO2, N2O, and N2O3 generated when ammonia is burned, "the denitration apparatus 43 is a denitration apparatus 43 that removes nitrogen oxides from combustion gas. The denitration apparatus 43 is provided with: a first catalyst pack 110 that is provided inside a housing 47 and through which combustion gas passes; a second catalyst pack 120 that is provided inside the housing 47 below the first catalyst pack 110 and through which combustion gas that has passed through the first catalyst pack 110 passes; a stand 140 that is provided between the first catalyst pack 110 and the second catalyst pack 120 and supports the first catalyst pack 110 on the second catalyst pack 120; and a steel frame part 150 that supports the second catalyst pack 120 relative to the housing 47" (Patent Document 1). Furthermore, as a technology for uniformly dispersing a fluid supplied to a catalyst pack or the like, for example, a fluid mixing device has been proposed (Patent Document 2), which includes "a nozzle 2 for injecting a gas or liquid different from the gas into a duct 1 with a square cross section, which serves as a flow path for the gas, and mixing plates 4, 4 protruding from the inner wall surfaces of a pair of opposing duct walls near the nozzle 2, and further mixing plates 5, 5 protruding from the inner wall surfaces at a position downstream of mixing plate 4 on the pair of opposing duct walls on the side where mixing plate 4 is not installed." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-121127 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-298814 Summary of the Invention [Problem to be solved by the invention]

[0004] Although the above-mentioned fluid mixing device technology can uniformly disperse the fluid (gas or liquid injected from the nozzle), there is a demand for even more uniform dispersion. An object of the present invention is to provide an exhaust gas treatment device that can uniformly disperse a reducing agent or the like in exhaust gas. [Means for solving the problem]

[0005] The exhaust gas treatment device according to the present invention is an exhaust gas treatment device used for exhaust gas emitted from an internal combustion engine and containing NOx (NO, NO2, N2O, N2O3, etc.), which is an oxide of nitrogen, and includes a cylindrical body having an inlet through which the exhaust gas flows and an outlet through which the exhaust gas flowing in from the inlet flows out, and the cylindrical body has, between the inlet side and the outlet side, a first region and a second region in this order from the inlet side, and the first region includes a first discharge portion for discharging a reducing agent, a swirling portion for swirling the exhaust gas that has flowed into the first region, and a reducing agent disposed on the second region side relative to the first discharge portion and the swirling portion. The second region is provided with a first catalyst portion having one or more second discharge holes for discharging the reducing agent, a first plate portion arranged on the outlet side of the second discharge portion, a second plate portion arranged on the outlet side of the first plate portion, and a second catalyst portion arranged on the outlet side of the second plate portion, the first plate portion and the second plate portion being orthogonal to a central axis of the second region, and first openings being formed on both end sides of the first plate portion in a first direction orthogonal to the central axis, and the second plate portion having a second opening smaller than the first plate portion between the first openings on both sides in the first direction. [Effects of the Invention]

[0006] According to the exhaust gas treatment device of the present invention, the reducing agent and the like can be uniformly dispersed in the exhaust gas. This allows exhaust gas in which the reducing agent and the like are uniformly dispersed to be supplied to the catalyst, thereby achieving high treatment capacity. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a conceptual diagram of an embodiment. [Figure 2] 1A and 1B are perspective views of a denitration device according to an embodiment, in which FIG. 1A is a view seen from one side in a first direction, and FIG. 1B is a view seen from the other side in the first direction. [Figure 3] FIG. 3 is a cross-sectional view of the denitration device perpendicular to the second direction. [Figure 4] FIG. 4 is a perspective view of the cross section of FIG. 3. [Figure 5] (a) is a view of the denitration device from a first direction, (b) is a cross-sectional view of the XX section of Figure 4(a) from the direction of the arrow, and (c) is a cross-sectional view of the YY section of Figure 4(a) from the direction of the arrow. [Figure 6] 1A and 1B are diagrams for explaining an analytical model, in which (a) shows the dimensions of Example A and Comparative Examples A and B, and (b) shows the dimensions of Comparative Example C. FIG. [Figure 7] 1(a) shows the configurations of Example A and Comparative Examples A to C, and FIG. 1(b) shows the analysis results. [Figure 8] Analysis of the pitch of the first outlet holes in the first region [Figure 9] Analysis of the blade angle of the first region of the swirl [Figure 10] Analysis of the wing span of the first region turning section [Figure 11] Analysis of the first opening in the second region [Figure 12] Analysis of the second opening in the second region [Figure 13] Analysis of the size of the second opening in the second region in the first direction [Figure 14] Analysis of the size of the second opening in the second region in the second direction [Figure 15] Analysis of the distance between the first catalyst section and the first plate section in the second region [Figure 16] Analysis of the distance between the first plate part and the second plate part in the second region [Figure 17] Analysis of the distance between the second plate section and the second catalyst section in the second region [Figure 18] Analysis of the distance between the second pipes in the second region [Figure 19] Analysis of the pitch of the second outlet holes of the second pipe in the second region [Figure 20] FIG. 10 is an explanatory diagram illustrating a case where two second openings are provided in the second plate portion. [Figure 21] Analysis of the distance between the two secondary apertures DETAILED DESCRIPTION OF THE INVENTION

[0008] <Embodiment> 1. Overview As shown in FIG. 1, the exhaust gas treatment device according to this embodiment is for converting exhaust gas emitted from an internal combustion engine 1 into clean gas. An example of this device is a denitration device 3 used for exhaust gas that is emitted from an internal combustion engine 1 and contains NOx such as N2O. The internal combustion engine 1 here uses a so-called ammonia co-fuel combustion, which is a mixture of fossil fuel and ammonia, and the exhaust gas contains NOx such as N2O. The denitration device 3 mixes a reducing agent with the exhaust gas and supplies the mixed exhaust gas to a denitration catalyst, thereby removing NOx such as N2O in the exhaust gas through a reduction reaction, thereby producing a clean gas (exhaust gas).

[0009] 2.Denitration equipment (1) Overview As shown in FIG. 2, the denitration device 3 includes a cylindrical body 5 having an inlet 3a through which exhaust gas flows and an outlet 3b through which the exhaust gas that has flowed in from the inlet 3a flows out. 3, the cylindrical body 5 has at least a first region 51 and a second region 53 in this order from the inlet 3a side between the inlet 3a and the outlet 3b. Here, the cylindrical body 5 has a third region 55 on the opposite side of the second region 53 from the first region 51 (the outlet 3b side). The third region 55 may be included in the second region 53. As shown in Figures 3 and 4, the first region 51 is provided with a first discharge section 511 for discharging a reducing agent, a swirling section 513 for swirling the exhaust gas that has flowed into the first region 51, and a first catalyst section 515 arranged on the second region 53 side of the first discharge section 511 and the swirling section 513. The second region 53 is provided with a second discharge section 531 for discharging the reducing agent, a first plate section 533 arranged on the outlet 3b side of the second discharge section 531, a second plate section 535 arranged on the outlet 3b side of the first plate section 533, and a second catalyst section 537 arranged on the outlet 3b side of the second plate section 535. 3 and 4, the first plate portion 533 is provided so that first openings 533a are formed on both end sides in a first direction perpendicular to the central axis (also referred to as the "second central axis") of the second region 53. The second plate portion 535 has a second opening 535a that is smaller than that of the first plate portion 533. The first region 51 is the region from the inlet 3a to the outlet 3b side end of the first catalyst section 515, the second region 53 is the region from the outlet 3b side end of the first catalyst section 515 to the outlet 3b side end of the second catalyst section 537, and the third region 55 is the region from the outlet 3b side end of the second catalyst section 537 to the outlet 3b.

[0010] The exhaust gas that flows in from the inlet 3a of the denitration device 3 configured as described above has a reducing agent discharged from the first discharge section 511 of the first region 51, passes through the downstream swirl section 513 where the reducing agent is diffused, and is then supplied to the first catalyst section 515. In the first catalyst section 515, NH3 and the like contained in the exhaust gas are decomposed to generate N2 and H2O. The generated N2 and H2O flow directly toward the outlet 3b. The exhaust gas that has passed through the first catalyst section 515 and flowed into the second region 53 has a reducing agent discharged from the second discharge section 531. The reducing agent is diffused as the exhaust gas passes through the first opening 533a between the first plate section 533 and the cylindrical body 5 and the second opening 535a of the second plate section 535, and is then supplied to the second catalyst section 537. In the second catalyst section 537, NOx such as N2O contained in the exhaust gas is reduced to generate N2 and H2O. The generated N2 and H2O directly flow toward the outlet 3b. Each part will be explained below.

[0011] (2) First area (2-1) First cylindrical part The first region 51 is formed by a first cylindrical portion 52, as shown in FIGS. The first cylindrical portion 52 is composed of at least a small-diameter cylindrical portion 521 having the inlet 3a, and a large-diameter cylindrical portion 522 connected to the second region 53. Here, the first cylindrical portion 52 has an inclined cylindrical portion 523 that connects the small-diameter cylindrical portion 521 and the large-diameter cylindrical portion 522 and is inclined so that the diameter increases (expands) from the small-diameter cylindrical portion 521 toward the large-diameter cylindrical portion 522. This allows the exhaust gas (which may contain a reducing agent or may simply be referred to as "exhaust gas") flowing inside small-diameter cylindrical portion 521 to flow into large-diameter cylindrical portion 522 with low resistance. The large-diameter cylindrical portion 522 has a cylindrical cross section that is quadrangular, such as a square or rectangle, a polygonal shape with more than a square, a circle, an ellipse, an oval, or a combination of these. Here, it has a rectangular cross section. In the cross section, the direction in which the short sides of the rectangle extend is the first direction, the direction in which the long sides extend is the second direction, and the direction perpendicular to the first and second directions is the third direction. Here, the first direction coincides with the up-down direction. The small-diameter cylindrical portion 521 has a cylindrical cross section that may be circular, elliptical, oval, polygonal (preferably four or more angles), or a combination of these. Here, it is cylindrical. The small-diameter cylindrical portion 521 has a small-diameter upstream portion 521a extending in a first direction, a small-diameter downstream portion 521b extending in a second direction, and a small-diameter midstream portion 521c connecting the small-diameter upstream portion 521a and the small-diameter downstream portion 521b in a bent state, forming an "L" shape as a whole with a curved middle portion. The diameter (dimension) of the small-diameter cylindrical portion 521 is configured to be constant and not change along the central axis of the small-diameter cylindrical portion 521.

[0012] The ratio of the long side to the short side of the large-diameter cylindrical portion 522 (long side / short side) is preferably 1.0 to 2.5. The ratio of the short side of the large diameter cylindrical portion 522 to the diameter of the small diameter cylindrical portion 521 (short side / diameter) is preferably 1.0 to 4.5. This allows the exhaust gas to be easily diffused when it flows from the small diameter cylindrical portion 521 into the large diameter cylindrical portion 522. The ratio (length / diameter) of the length of inclined cylindrical portion 523 in the third direction to the diameter of small diameter cylindrical portion 521 is preferably 0.3 to 1.2, which makes it easier for exhaust gas to diffuse when it flows from small diameter cylindrical portion 521 to large diameter cylindrical portion 522. Here, the central axis of the large-diameter cylindrical portion 522 and the central axis of the small-diameter downstream portion 521b of the small-diameter cylindrical portion 521 are substantially the same. The first central axis, which is the central axis of the first region 51, is the central axis of the space that constitutes the space of the first region 51 and is also the central axis of the first cylindrical portion 52.

[0013] (2-2) First discharge part 3 and 4, the first discharge section 511 includes a first pipe 524, and a plurality of first discharge holes (not shown) are formed in the first pipe 524. The plurality of first discharge holes are formed at intervals in the longitudinal direction of the first pipe 524. The first pipe 524 is provided in the small diameter upstream portion 521a of the small diameter cylindrical portion 521. Here, the first pipe 524 is arranged so as to pass through the center of the small diameter upstream portion 521a and to be perpendicular to the central axis. The shape of the first discharge holes may be circular, elliptical, oval, polygonal, or a combination thereof, and here, they are circular. The diameter of the first discharge holes is preferably 0.5 to 6.0 mm. The size and number of the first discharge holes are appropriately determined depending on the discharge amount of the reducing agent, the flow velocity of the exhaust gas, etc.

[0014] (2-3) Rotating section The swirl section 513 swirls the exhaust gas containing the reducing agent so as to mix the reducing agent discharged from the first discharge section 511 into the exhaust gas. The swirl section 513 is configured, for example, with a static mixer 525. The static mixer 525 is disposed inside the small diameter upstream section 521a of the small diameter cylindrical section 521 and on the upstream side of the first discharge section 511. As shown in the enlarged view of FIG. 3, the static mixer 525 includes a plurality of swirl vanes 525a that are fixedly arranged radially from the central axis (first central axis) of the small diameter upstream section 521a. That is, the static mixer 525 is of a paddle vane type, and includes four swirl vanes 525a in this example. Note that central portion 525b where multiple swirler blades 525a of static mixer 525 are joined is located on the central axis of small-diameter upstream portion 521a. Furthermore, swirler blades 525a are inclined at a predetermined angle (hereinafter referred to as "blade angle") F with respect to the flow direction of the exhaust gas, as shown in the enlarged view of FIG.

[0015] (2-4) First catalyst section The first catalyst section 515 decomposes NH3 in the exhaust gas and the reducing agent (ammonia) discharged by the first discharge section 511, and by using the heat generated at that time to raise the exhaust gas temperature, it promotes the decomposition of NOx such as N2O in the second catalyst section. A so-called CR reactor that uses a denitration catalyst is used as the first catalyst section 515. The first catalyst section 515 includes a plurality of cells 526 with a honeycomb structure. The first catalyst section 515 is disposed inside the large diameter cylindrical section 522. The first catalyst section 515 includes plate-shaped cells 526 that are perpendicular to the central axis of the large diameter cylindrical section 522. The plurality of cells 526 are provided with their through holes facing the third direction.

[0016] (3)Second area (3-1)Second cylinder part The second region 53 is formed by a second cylindrical portion 54 . The second cylindrical portion 54 is configured to have the same shape and size as the large-diameter cylindrical portion 522 of the first cylindrical portion 52. The large-diameter cylindrical portion 522 of the first cylindrical portion 52 and the second cylindrical portion 54 are configured as a single cylindrical body. This allows the exhaust gas that has passed through the first region 51 (first cylindrical portion 52) to be supplied (flow) smoothly to the second region 53. The second cylindrical portion 54 has a cylindrical cross section that is quadrangular such as a square or rectangle, a polygonal shape with more than a square, a circle, an ellipse, an oval, or a combination of these. Here, the cross section is a rectangular cylindrical shape that is elongated in the second direction, the same as the large-diameter cylindrical portion 522. The second cylindrical portion 54 is configured so that its cross-sectional shape and dimensions do not change along its second central axis, which is its central axis. The ratio of the long side to the short side of the second cylindrical portion 54 (long side / short side) is preferably 1.0 to 2.5. The ratio of the short side of the second cylindrical portion 54 to the diameter of the small diameter cylindrical portion 521 (short side / diameter) is preferably 1.0 to 4.5. Here, the second central axis of the second cylindrical portion 54 substantially coincides with the central axis of the large-diameter cylindrical portion 522 of the first cylindrical portion 52. The second central axis, which is the central axis of the second region 53, is the central axis of the space that constitutes the space of the second region 53 and is also the central axis of the second cylindrical portion 54.

[0017] (3-2)Second discharge part 3 and 4, the second discharge section 531 includes a second pipe 541, and a plurality of second discharge holes 541a are formed in the second pipe 541. The plurality of second discharge holes 541a are formed at intervals in the longitudinal direction of the second pipe 541. There are two second pipes 541, which extend in the second direction and are spaced apart in the first direction, so that the second discharge holes 541a are formed at intervals in the second direction. 3 and 4, the two second pipes 541 are arranged so as to sandwich the second central axis 59 of the second cylindrical portion 54. This allows the reducing agent to be discharged evenly in the first direction. Alternatively, the reducing agent can be discharged in a dispersed state.

[0018] The shape of the second discharge holes (not shown) may be circular, elliptical, oval, polygonal, or a combination of these, and here they are circular. The second discharge holes of the two second pipes 541 are formed at the same intervals and with the same size. The diameter of the second discharge holes is preferably 0.5 to 6.0 mm, but the size of the second discharge holes is appropriately set depending on the discharge amount of the reducing agent, the flow velocity of the exhaust gas, etc. The second discharge holes are formed toward the downstream side in the third direction (a direction parallel to the second central axis 59). "Toward the downstream side in the third direction" includes "toward the downstream side in a direction parallel to the third direction" and "toward the downstream side on the outer side in the first direction with respect to the third direction." This allows the reducing agent to be discharged in a dispersed state. Note that "toward the downstream side on the outer side in the first direction" means toward the downstream side on one side in the first direction in the case of the second pipe 541 located on one side in the first direction, and toward the downstream side on the other side in the first direction in the case of the second pipe 541 located on the other side. The outward direction of the first direction is a direction inclined at an angle of 90 degrees or less with respect to the first direction.

[0019] (3-3) 1st plate part The first plate portion 533 is arranged so as to be perpendicular to or intersect with the second central axis 59 of the second region 53. Here, it is arranged so as to be approximately perpendicular. Note that "approximately perpendicular" refers to a state in which the first plate portion 533 intersects with the direction perpendicular to the second central axis 59 at an angle within a range of -10 to 10 degrees. The first plate portion 533 is arranged in a first direction so that a first opening 533a is formed between the second region first wall portion 54a and the second region second wall portion 54b that are perpendicular to the first direction and that constitute the second tubular portion 54. The second region first wall portion 54a and the second region second wall portion 54b are the long side portions when the second cylindrical portion 54 has a rectangular cylindrical shape. The first plate portion 533 here is formed from a single plate member, and is attached at both ends in the second direction to the second region third wall portion 54c and the second region fourth wall portion 54d of the second tubular portion 54 (see Figure 1). The first opening 533a has a shape that is long in the second direction, such as a rectangular shape, an oval shape, an elliptical shape, a shape that is a combination of these, or a square shape, a circle, etc. Here, the first opening 533a has a rectangular shape. This allows the first plate portion 533 to be provided easily and inexpensively. The first opening 533a provided on both sides in the first direction may be one or more in the second direction.

[0020] (3-4)Second plate part The second plate portion 535 is disposed so as to be perpendicular to or intersect with the second central axis 59 of the second region 53. In this example, the second plate portion 535 is disposed so as to be substantially perpendicular to the second central axis 59. The second plate portion 535 is provided so that one or more second openings 535a are formed therein. Here, the second plate portion 535 is made of a single plate member and has one or more second openings 535a, which makes it possible to provide the second openings 535a easily and inexpensively. The second plate portion 535 has a second opening 535a in its central portion. Here, "having a second opening 535a in its central portion" means that the second central axis 59 passes through the second opening 535a. Note that if there are multiple second openings 535a, this means that there is a single circular opening at the center of the multiple second openings 535a, with the opening having the same area as the total opening area of ​​the multiple second openings 535a, and the central axis passes through that opening. When viewed from the direction in which the second central axis 59 extends, the second opening 535a is located between the first openings 533a on both sides in the first direction. The second plate portion 535 has an end portion in at least one of the first and second directions attached to the inner surface of the second cylindrical portion 54. Here, both ends in the first and second directions are attached to the inner surface of the second cylindrical portion 54 (the inner surfaces of the second region first to fourth wall portions 54a to 54d). This makes it possible to prevent exhaust gas from passing between the second plate portion 535 and the inner surface of the second cylindrical portion 54. Second opening 535a has, for example, a rectangular shape, an oval shape, an elliptical shape, a triangular shape or a polygonal shape with five or more sides, or a shape that is a combination of these. Here, second opening 535a has a rectangular shape that is long in the second direction.

[0021] (3-5)Second catalyst section The second catalyst section 537 promotes the reaction between NOx such as N2O in the exhaust gas and the reducing agent (ammonia) discharged by the first discharge section 511 and the second discharge section 531 by catalytic action. The second catalyst section 537 uses a so-called CR reactor that uses a denitration catalyst. The second catalyst section 537 includes a plurality of cells 538 with a honeycomb structure. The second catalyst portion 537 is disposed inside the second cylindrical portion 54. The second catalyst portion 537 includes plate-shaped cells 538 that are perpendicular to the second central axis 59 of the second region 53. The plurality of cells 538 are provided with their through holes facing the third direction.

[0022] (4) Third area The third region 55 is formed by a third cylindrical portion 56, as shown in FIGS. The third cylindrical portion 56 is composed of at least a small-diameter cylindrical portion having the outlet 3b, and a large-diameter cylindrical portion 563 connected to the second region 53. Here, it has an inclined cylindrical portion 565 that connects the small-diameter cylindrical portion 561 and the large-diameter cylindrical portion 563 and is inclined so as to become larger (expanded in diameter) from the small-diameter cylindrical portion 561 toward the large-diameter cylindrical portion 563. The small diameter cylindrical portion 561 has a cylindrical cross section that may be circular, elliptical, oval, polygonal (preferably with four or more sides), or a combination of these.Here, it has a cylindrical shape. The large-diameter cylindrical portion 563 has a cylindrical shape whose cross section is quadrangular such as a square or a rectangle, a polygonal shape with more than a square, a circle, an ellipse, an oval, a combination of these, etc. Here, like the second cylindrical portion 54, the large-diameter cylindrical portion 563 has a rectangular cross section. Here, the central axis of small diameter cylindrical portion 561 and the central axis of large diameter cylindrical portion 563 are offset in the first direction. These central axes may or may not coincide with each other, but are preferably parallel.

[0023] 3.Analysis results (1) Overall An analysis was conducted on the concentration distribution of a reducing agent (ammonia) when it was injected into exhaust gas. The analysis was conducted using the dimensions shown in Figure 6(a). Note that "A" in Figure 6(a) and other characters are shown in Figures 3 and 5. The diameter (inner diameter) of the first pipe 524 of the first discharge part 511 is 15.7 mm, and the pitch (center-to-center distance between holes) of the first discharge holes is 50 mm. The diameter (inner diameter) of the second pipe 541 of the second discharge part 531 is 15.7 mm, and the pitch (center-to-center distance between holes) of the second discharge holes is 92 mm. The discharge amount of the first discharge part 511 is 29 Nm 3 / hr, and the discharge rate of one of the second pipes 541 constituting the second discharge section 531 is 2.8 Nm 3 / hr, and the flow rate of the exhaust gas flowing into the inlet 3a is 10 Nm 3 / hr. There are four analytical models, as shown in Figure 7(a). In Example A, the first region 51 includes a first discharge portion 511 and a swirl portion 513, and the second region 53 includes a second discharge portion 531, a first plate portion 533, and a second plate portion 535. Comparative Example A has a first discharge portion 511 in the first region 51 and does not have a swirl portion. The second region 53 is the same as Example A. Comparative Example B includes second discharge portion 531 in second region 53, and does not include first plate portion 533 and second plate portion 535. First region 51 is the same as in Example A. In Comparative Example C, the first region 51 is the same as the first region 51 of Example A, and the second region is a model of the prior art (Japanese Patent Application Laid-Open No. 2004-298814), details of which are as shown in FIG. 6(b). In this embodiment, as shown in FIG. 7(b), the target range of the concentration (ppm) at the inlet of the first catalyst section 515 is 3,980 to 5,970, and the target range of the concentration (ppm) at the inlet of the second catalyst section 537 is 1,013 to 1,519.

[0024] FIG. 7(b) shows the analysis results of Example A and Comparative Examples A to C. In Example A, the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range. In comparative example A, the concentration at the inlet of first catalyst section 515 is not within the target range, and the concentration at the inlet of second catalyst section 537 is within the target range. Example A and Comparative Example A reveal the following. (a) In the first region 51, the swirling portion 513 provides a higher diffusibility of the reducing agent. (b) Even if the diffusibility is insufficient in the first region 51, the diffusibility can be sufficient in the second region 53.

[0025] In Comparative Example B, the concentration at the inlet of the first catalyst section 515 is within the target range, but the concentration at the inlet of the second catalyst section 537 is not within the target range. Example A and Comparative Example B reveal the following. (c) In the second region 53, the first plate portion 533 and the second plate portion 535 are provided, thereby making it possible to increase the diffusibility of the reducing agent. In Comparative Example C, the concentration at the inlet of the first catalyst section 515 is within the target range, but the concentration at the inlet of the second catalyst section 537 is not within the target range. The following can be seen from Example A and Comparative Examples A and C. (d) Example A and Comparative Example A can increase the diffusibility of the reducing agent in the second region more than Comparative Example C.

[0026] In Example A, the temperature difference at the outlet of the first catalyst section 515 is 13°C, and the temperature difference at the inlet of the second catalyst section 537 is 4°C. In Comparative Example A, the temperature difference at the outlet of the first catalyst section 515 is 94°C, and the temperature difference at the inlet of the second catalyst section 537 is 17°C. Example A and Comparative Example A reveal the following. (e) In the first region 51, the temperature difference is smaller when the swirling section 513 is provided, and ammonia is decomposed uniformly. (f) The temperature difference between the first region 51 and the second region 53 is smaller in the second region 53, and even if the diffusibility of the reducing agent is insufficient in the first region 51, the reducing agent can be sufficiently diffused in the second region 53.

[0027] In Comparative Example B, the temperature difference at the outlet of the first catalyst section 515 is 14°C, and the temperature difference at the inlet of the second catalyst section 537 is 21°C. Example A and Comparative Example B reveal the following. (g) Since the configuration of the first region 51 is the same, the temperature difference is also almost the same, but by providing the first plate portion 533 and the second plate portion 535 in the second region 53, the temperature difference is reduced and the diffusibility of the reducing agent can be improved. In Comparative Example C, the temperature difference at the inlet of the first catalyst section 515 is 8°C, and the temperature difference at the inlet of the second catalyst section 537 is 39°C. The following can be seen from Example A and Comparative Examples A and C. (h) Example A and Comparative Example A can increase the diffusibility of the reducing agent in the second region more than Comparative Example C. The temperature of the exhaust gas flowing in from the inlet 3a of the denitration device 3 is 405°C, and the temperature of the exhaust gas is increased by the heat of decomposition of ammonia in the first region 51. Therefore, the first region 51 also has the function of increasing the temperature of the exhaust gas supplied so that the decomposition reaction can occur efficiently in the second region 53.

[0028] (2) First area (2-1) 1st discharge hole FIG. 8 shows the analysis results when only the pitch of the first discharge holes 524a is changed. In addition, the upper side of the plot in FIG. 8(c) indicates the maximum value in FIG. 8(b), and the lower side indicates the minimum value in FIG. 8(b), and the same is true for the other figures. Here, as shown in FIG. 8(a), the first hole pitch (pitch of the first discharge holes) is 50 mm in Example A, 30 mm in Example 10a, and 65 mm in Example 10b. As shown in Fig. 8(b), in Examples A, 10a, and 10b, the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "Good." Note that in Fig. 8(b), for convenience, "Example 10a" and the like are referred to as "Example 10a" and the like. 8(c), the pitch of the first discharge holes 524a that will result in a concentration within the target range can be estimated to be 24 to 65 mm. This is within the range of 5 to 15% (pitch / diameter) of the diameter of the small-diameter cylindrical portion 521 of the first cylindrical portion 52, or more precisely, 5.4 to 14.5%.

[0029] (2-2) Blade angle of the swirl section FIG. 9 shows the analysis results when only the blade angle (F) of the swirler 513 (static mixer 525) is changed. Here, as shown in FIG. 9(a), the blade angles (F) are 35° for Example A, 30° for Example 11a, 45° for Example 11b, and 25° for Comparative Example 11a. In Examples A, 11a, and 11b, as shown in FIG. 9(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." In contrast, in Comparative Example 11a with a small blade angle (F), the concentration at the inlet of first catalyst section 515 is not within the target range. Although Comparative Example 11a is inferior in diffusibility, it is possible to reduce pressure loss in first region 51. Furthermore, from Figure 9(c), the blade angle (F) at which the concentration falls within the target range can be estimated to be 28 to 55°.

[0030] (2-3) Wingspan of the turning part FIG. 10 shows the analysis results when only the wing width of the swirl section 513 is changed. As shown in FIG. 10(a), the blade widths are Example A of 100 mm, Example 12a of 90 mm, Example 12b of 130 mm, Example 12c of 150 mm, and Comparative Example 12a of 80 mm. In Examples A, 12a, and 12b, as shown in FIG. 10(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." In contrast, in Example 12c, which has a large blade width, the concentration at the inlet of first catalyst section 515 is within the target range, but the concentration at the inlet of second catalyst section 537 is not within the target range. Also, in Comparative Example 12a, which has a small blade width, the concentration at the inlet of first catalyst section 515 is not within the target range, but the concentration at the inlet of second catalyst section 537 is within the target range. 10(c), the blade width at which the concentration falls within the target range at the inlet of the first catalyst section 515 can be estimated to be 90 to 170 mm. Note that this (blade width / diameter) is 0.2 to 0.4 (20 to 38%) relative to the diameter (d) of the small diameter cylindrical section 521 of the first cylindrical section 52. 10(b), considering the concentration at the inlet of the second catalyst section 537, the blade width within the target range is preferably 80 to 140 mm, which is 0.2 to 0.3 (18 to 31%) (blade width / diameter) relative to the diameter (d) of the small diameter cylindrical section 521 of the first cylindrical section 52.

[0031] (3)Second area (3-1) First opening FIG. 11 shows the analysis results in which only the first opening 533a of the first plate portion 533 was changed. Here, as shown in FIG. 11(a), the first opening 533a is 150 mm in Example A, 100 mm in Example 20a, and 200 mm in Example 20b. In Examples A, 20a, and 20b, as shown in FIG. 11(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 11(c), the size of the first opening 533a at which the concentration falls within the target range at the inlet of the second catalyst section 537 (opening ratio = opening area / cross-sectional area) can be estimated to be 10 to 30%. The opening area is the total area of ​​both openings in the first direction, and the size in the first direction of one of the first openings 533a is 69 to 208 mm.

[0032] (3-2) Second opening FIG. 12 shows the analysis results when only the second opening 535a of the second plate portion 535 is changed. Here, as shown in FIG. 12(a), the second opening 535a is 500×850 mm in Example A, 400×750 mm in Example 21a, and 600×950 mm in Example 21b. In Examples A, 21a, and 21b, as shown in FIG. 12(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." Furthermore, the size of second opening 535a at which the concentration falls within the target range at the inlet of second catalyst section 537 (opening ratio=opening area / cross-sectional area) can be estimated to be 6 to 20% from FIG. 12(c).

[0033] (3-2-1) Size in the first direction FIG. 13 shows the analysis results when only the size (D) of second opening 535a of second plate portion 535 in the first direction is changed. Here, as shown in FIG. 13(a), the size (D) of the second opening 535a in the first direction is 500 mm in Example A, 400 mm in Example 22a, and 600 mm in Example 22b. In Examples A, 22a, and 22b, as shown in FIG. 13(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 13(c), the size (D) of the second opening 535a at which the concentration falls within the target range at the inlet of the second catalyst section 537 can be estimated to be 350 to 800 mm. Note that the size of the second opening 535a (opening ratio = opening area / cross-sectional area) can be estimated to be 9.0 to 20.5% when the size (E) in the second direction is 850 mm.

[0034] (3-2-2) Second direction size FIG. 14 shows the analysis results when only the size (E) of second opening 535a of second plate portion 535 in the second direction is changed. 14(a), the size (E) of the second opening 535a in the second direction is 850 mm in Example A, 750 mm in Example 23a, 950 mm in Example 23b, and 425 mm in Example 23c. Examples A, 23a, and 23b have one second opening 535a, while Example 23c has two second openings 535a. In Examples A, 23a, 23b, and 23c, as shown in FIG. 14(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 14(c), the size (E) of the second opening 535a at which the concentration falls within the target range at the inlet of the second catalyst section 537 can be estimated to be 680 to 1000 mm. Note that the size of the second opening 535a (opening ratio = opening area / cross-sectional area) can be estimated to be 10.3 to 15.1% when the size (D) in the first direction is 500 mm.

[0035] (3-2-3) Overlapping portion of the first plate portion and the second plate portion 11(c) and 12(c), when the second region 53 is projected in the flow direction from the inlet 3a side toward the outlet 3b side, the area of ​​the portion where the first plate portion 533 and the second plate portion 535 overlap is within a range of 50 (0.80-0.30) to 84 (0.94-0.1)% of the cross-sectional area of ​​the second region 53. Here, the maximum value is determined by subtracting the minimum opening area of ​​the first openings 533a of the first plate portion 533 from the maximum area of ​​the portion where the second openings 535a of the second plate portion 535 are not present, and the minimum value is determined by subtracting the maximum opening area of ​​the first openings 533a of the first plate portion 533 from the minimum area of ​​the portion where the second openings 535a of the second plate portion 535 are not present, and dividing the result by the cross-sectional area of ​​the second region 53.

[0036] (3-3) Distance between the first catalyst part and the first plate part (L1) FIG. 15 shows the analysis results when only the distance (L1) between first catalyst portion 515 and first plate portion 533 was changed. Here, as shown in FIG. 15(a), the distance (L1) is 300 mm in Example A, 450 mm in Example 24a, and 150 mm in Example 24b. In Examples A, 24a, and 24b, as shown in FIG. 15(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 15(c), the distance (L1) at which the concentration falls within the target range at the inlet of the second catalyst section 537 can be estimated to be 100 to 500 mm. -5 ~15.1×10 -5 is within the range. Furthermore, L1 / (L1+L2+L3) can be estimated to be 14.3 to 45.5%.

[0037] (3-4) Distance between the first plate and the second plate (L2) FIG. 16 shows the analysis results when only the distance (L2) between the first plate portion 533 and the second plate portion 535 is changed. Here, as shown in FIG. 16(a), the distance (L2) is 300 mm for Example A, 240 mm for Example 25a, 450 mm for Example 25b, 150 mm for Comparative Example 25a, and 200 mm for Comparative Example 25b. In Examples A, 25a, and 25b, as shown in FIG. 16(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 16(c), the distance (L2) at which the concentration falls within the target range at the inlet of the second catalyst section 537 can be estimated to be 210 to 470 mm. -5 ~14.2×10 -5 is within the range. Furthermore, L2 / (L1+L2+L3) can be estimated to be 26.0 to 43.9%.

[0038] (3-5) Distance between the second plate and the second catalyst (L3) FIG. 17 shows the analysis results when only the distance (L3) between second plate portion 535 and second catalyst portion 537 was changed. Here, as shown in FIG. 17(a), the distance (L3) is 300 mm for Example A, 200 mm for Example 26a, 450 mm for Example 26b, and 150 mm for Comparative Example 26a. In Examples A, 26a, and 26b, as shown in FIG. 17(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 17(c), the distance (L3) at which the concentration falls within the target range at the inlet of the second catalyst section 537 can be estimated to be 180 to 520 mm. -5 ~15.7×10 -5is within the range. Furthermore, L3 / (L1+L2+L3) can be estimated to be 23.1 to 46.4%.

[0039] (3-6) Distance of the second discharge section (second pipe) (L4) FIG. 18 shows the analysis results when only the interval (L4) of the second discharge portion 531 is changed. Here, as shown in FIG. 18(a), the distance (L4) is 464 mm in Example A, 200 mm in Example 27a, and 700 mm in Example 27b. In Examples A, 27a, and 27b, as shown in FIG. 18(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 18(c), the distance (L4) at which the concentration falls within the target range at the inlet of the second catalyst section 537 can be estimated to be 190 to 900 mm. Note that the distance (L4) (L4 / B) is 14 to 65%, or more precisely 13.7 to 64.8%, relative to the size (B) of the second tubular section 54 in the second direction.

[0040] (3-7)Second discharge hole Figure 19 shows the analysis results when only the pitch of the second discharge holes was changed. Here, as shown in FIG. 19(a), the second hole pitch (pitch of the second discharge holes) is 92 mm in Example A, 81 mm in Example 28a, and 111 mm in Example 28b. In Examples A, 28a, and 28b, as shown in FIG. 19(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 19(c), the pitch of the second discharge holes that will result in a concentration within the target range can be estimated to be 74 to 125 mm, which is 3 to 5% (pitch / A) relative to the size (A) of the second cylindrical portion 54 in the second direction, or more precisely, 3.1 to 5.2 (%).

[0041] (4) Other FIG. 21 shows the analysis results when two second openings 535a are provided in the second plate portion 535 and only the interval (G) in the first direction is changed as shown in FIG. 20(b). Here, as shown in FIGS. 20(a) and 21(a), the spacing between the second openings 535a is 0 mm in Example A, 150 mm in Example 50a, 200 mm in Example 50b, and 296 mm in Comparative Example 50a. In Example A, there is one second opening 535a, but two openings with half the size in the first direction are provided with a gap of 0 mm. The size (H x E) of one opening is 250 mm x 850 mm. In Examples A, 50a, and 50b, as shown in FIG. 21(b), the concentrations at both the inlets of the first catalyst section 515 and the second catalyst section 537 are within the target range, and the result is "good." 21(c), the distance (G) between the second openings 535a at which the concentration falls within the target range at the inlet of the second catalyst section 537 can be estimated to be 0 to 270 mm. This is (G / B) with respect to the size (B) of the second cylindrical section 54 in the first direction, and is 0 to 19.5 (%).

[0042] <Modification> Although the present invention has been described above based on the embodiment, it is not limited to this embodiment. For example, the embodiment may be appropriately combined with the modified examples described below, or multiple modified examples may be appropriately combined.

[0043] 1. Internal combustion engine Although an ammonia-mixed fuel, which is a mixture of a fossil fuel and ammonia, was used as the fuel, a fuel mainly composed of ammonia may also be used. Note that "mainly" here means that it comprises more than half of the total, or that it is mixed at the highest ratio. Furthermore, when the exhaust gas treatment device is a denitration device, any fuel that causes the exhaust gas to contain NOx such as N2O may be used. In other words, any fuel that causes the exhaust gas to contain NOx such as N2O may be used.

[0044] 2. Exhaust gas treatment equipment (denitrification equipment) (1) Overall Although the exhaust gas treatment device has been described as a denitration device that performs denitration treatment to remove NOx such as N2O, it may also be, for example, a decomposition treatment device that performs a process to decompose ammonia. The fluid treatment device may also perform a dispersion treatment to disperse the treatment agent in the fluid into which the treatment agent has been discharged.

[0045] (2) First area (a) The first cylindrical portion 52 has a small diameter cylindrical portion 521, a large diameter cylindrical portion 522, and an inclined cylindrical portion 523, but may be a cylindrical portion with a constant cross-sectional shape or a cylindrical portion with constant dimensions. (b) The first cylindrical portion 52 has an "L" shape as a whole, but may have a straight line, and the small-diameter upstream portion 521a extends in a first direction, but may extend in a second direction or a direction intersecting the first direction or the second direction. The shape of the first cylindrical portion 52 may be appropriately determined depending on the arrangement relative to the internal combustion engine 1. (c) The large diameter cylindrical portion 522 has a rectangular shape that is long in the second direction, but may have a rectangular shape that is long in the first direction. (d) The central axes of the large diameter cylindrical portion 522 and the inclined cylindrical portion 523 and the central axis of the small diameter downstream portion 521b of the small diameter cylindrical portion 521 may or may not substantially coincide with each other. (e) For the swirling section 513, a paddle-type static mixer 525 is used, but any mixer that can swirl the exhaust gas flowing in can be used, for example, a static mixer with a twisted blade element. If swirling ability is not a consideration, a mixer that combines a restrictor and a resistance plate, a mixer that expands or reduces the pipe diameter, etc. can be used. The static mixer 525 has four paddle blades, but may have three or five or more paddle blades. (f) The first catalyst section 515 has cells 526 with a honeycomb structure, but may have a structure with fine interconnecting holes, a mesh structure like a sintered filter, a pellet-type structure, or the like, as long as it has a sufficient contact area with the exhaust gas and can support the catalyst. (g) Although the inclined tube portion 523 was provided between the small diameter tube portion 521 and the large diameter tube portion 522, it may not be necessary, or the first catalyst portion 515 may be provided inside the inclined tube portion 523 that is elongated in the third direction.

[0046] (3)Second area (a) The second cylindrical portion 54 may be a cylindrical portion having a constant cross-sectional shape or constant dimensions, or the cross-sectional shape or dimensions may vary along the second central axis 59. (b) The second cylindrical portion 54 has a rectangular shape that is long in the second direction, but may also have a rectangular shape that is long in the first direction. Furthermore, the cross-sectional shape and dimensions may be the same as or different from those of the large-diameter cylindrical portion 522 of the first cylindrical portion 52. (c) The second central axis 59 of the second cylindrical portion 54 and the central axis of the large diameter cylindrical portion 522 of the first cylindrical portion 52 may or may not substantially coincide with each other. (d) The second discharge section 531 includes two second pipes 541, but may include one or three or more second pipes 541. When three or more second pipes 541 are included, the positions and pitches of the second discharge holes may be different between adjacent second pipes 541. (e) The second pipe 541 is arranged to extend in the second direction, but may also be arranged to extend in the first direction, or may be arranged to be inclined relative to the first direction or the second direction, or may be, for example, a single pipe with a folded middle portion to form a "U" shape. (f) The direction in which the multiple second discharge holes face may be one type or multiple types, the second discharge holes of the two second pipes 541 may be the same or different, and they may be arranged so as to be symmetrical about the second central axis 59 or so as to be asymmetrical about the second central axis 59. The second discharge hole faces downstream in the third direction (this is an example of a case where there is only one type of facing direction), but if multiple second discharge holes 541a are formed in one second pipe 541, they may face in multiple directions, at least one side of one side and the other side of the first direction and the downstream side (this is an example of a case where there are multiple types of facing directions), or they may face in two directions, the downstream side and the upstream side of the third direction (this is an example of a case where there are multiple types of facing directions).

[0047] (g) The second pipes 541 may be provided in one or more stages along the direction in which the second central axis 59 of the second region 53 extends (that is, the third direction). The second discharge hole may be arranged singly in a direction passing through the center (axis) of the second pipe 541 and parallel to the second central axis 59, or may be arranged at a position offset from the center (axis) of the second pipe 541. (h) The plurality of second discharge holes aligned in the second direction may be arranged at equal intervals, or may be arranged so that the intervals become smaller or larger from the end toward the center in the second direction. (i) The multiple rows in which multiple second discharge holes are lined up in the second direction (multiple second pipes 541) may be arranged at intervals in the first direction across the second central axis 59, or may be arranged at intervals without sandwiching the central axis (such as when two second pipes 541 are arranged on one side or the other side of the second central axis 59 in the first direction). When multiple rows sandwich the central axis, the distance between the rows and the central axis may or may not be equal. The multiple rows (the multiple second pipes 541) may or may not be parallel to the second direction, or may include parallel rows and non-parallel rows. (j) The first opening 533a is formed between the end face of the first plate portion 533 in the first direction and the inner surface of the second region 53 (the inner surface of the second region first wall portion 54a or the second region second wall portion 54b), but it may also be an opening formed on both end sides of the first plate portion 533 in the first direction, or if a rib portion is formed extending in the first direction from the inner surface of the second tubular portion 54 toward the second center axis 59, an opening may be provided in that rib portion. (k) The second opening 535a may be a single opening in the center, or multiple openings 535a may be provided around the second central axis 59. In this case, the total opening area of ​​the multiple second openings 535a is smaller than the area of ​​the first plate portion 533. (l) The first plate portion 533 may be made up of one plate member, or may be made up of multiple plate members arranged in the first direction or the second direction. (m) The second plate portion 535 may be formed of a single plate member, or may be formed of multiple plate members arranged in the first direction or the second direction. In this case, the second opening 535a may be formed across one or multiple plate members. Furthermore, if there are multiple second openings 535a, one or more second openings 535a may be formed in at least two or more of the multiple plate members. (n) The second catalyst section 537 has cells 538 with a honeycomb structure, but may have a structure with fine interconnecting holes, a mesh-like structure like a sintered filter, a pellet-type structure, or the like, as long as it has a sufficient contact area with the exhaust gas and can support the catalyst.

[0048] (4) Other Second Area The first discharge part 511 and the second discharge part 531 discharge reducing agents of the same or substantially the same composition, but they may also discharge reducing agents of different compositions. In the case of a denitration device, a reducing agent containing ammonia is preferred. The first catalyst 515 and the second catalyst section 537 use a denitration catalyst, but may use, for example, an ammonia decomposition catalyst. The second catalyst section 537 uses the same denitration catalyst as the first catalyst section 515, but may use a different catalyst, for example, an ammonia decomposition catalyst, a CO oxidation catalyst, or the like.

[0049] <Invention> 1. Invention 1 Although the fluid mixing device technology of Patent Document 2 can disperse fluids uniformly, there is a demand for even more uniform dispersion. An object of the present invention 1 is to provide an exhaust gas treatment device that can uniformly disperse exhaust gas. The first exhaust gas treatment device according to the first invention comprises: An exhaust gas treatment device used for exhaust gases emitted from an internal combustion engine and containing NOx, a cylindrical body having an inlet through which the exhaust gas flows and an outlet through which the exhaust gas that has flowed in from the inlet flows out, the cylindrical body has a first region and a second region in this order from the inlet side between the inlet side and the outlet side, the first region is provided with a first discharge portion for discharging a reducing agent, a swirling portion for swirling the exhaust gas that has flowed into the first region, and a first catalyst portion disposed on the second region side with respect to the first discharge portion and the swirling portion, The second region is provided with a second discharge portion having one or more second discharge holes for discharging the reducing agent, a first plate portion arranged on the outlet side of the second discharge portion, a second plate portion arranged on the outlet side of the first plate portion, and a second catalyst portion arranged on the outlet side of the second plate portion, the first plate portion and the second plate portion are perpendicular to the central axis of the second region, First openings are formed on both end sides of the first plate portion in a first direction perpendicular to the central axis, The second plate portion has a second opening smaller than the first plate portion and between the first openings on both sides in the first direction. According to the first exhaust gas treatment device of the present invention 1, the exhaust gas can be uniformly dispersed.

[0050] The second exhaust gas treatment device according to the first invention is the first exhaust gas treatment device, The total opening area of ​​the first openings on both sides in the first direction is within a range of 10 to 30% of the cross-sectional area of ​​the second region. A third exhaust gas treatment device according to the first invention is the first or second exhaust gas treatment device, The opening area of ​​the second opening is in the range of 6 to 20% of the cross-sectional area of ​​the second region. A fourth exhaust gas treatment device according to the first invention is any of the first to third exhaust gas treatment devices, When the second region is projected from the inlet side toward the outlet side, the second opening is located within the outer circumferential edge of the first plate portion. A fifth exhaust gas treatment device according to the first invention is any of the first to fourth exhaust gas treatment devices, When the second region is projected from the inlet side toward the outlet side, the area of ​​the portion where the first plate portion and the second plate portion overlap is within a range of 50 to 84% of the cross-sectional area of ​​the second region.

[0051] A sixth exhaust gas treatment device according to the first invention is any of the first to fifth exhaust gas treatment devices, the cylindrical body has a second cylindrical portion that forms the second region, the second cylindrical portion has a rectangular shape or a shape similar to the rectangular shape that is long in a second direction perpendicular to the first direction and the central axis of the second region, The first opening and the second opening have a rectangular shape that is long in the second direction or a shape similar to the rectangular shape. A seventh exhaust gas treatment device according to the first invention is any of the first to sixth exhaust gas treatment devices, In the second central axis direction in which the central axis of the second region extends, the distance from the inlet of the second region to the first plate portion is 3.0×10 with respect to the cross-sectional area of ​​the second region perpendicular to the second central axis direction. -5 ~15.1×10 -5 is within the range of An eighth exhaust gas treatment device according to the first invention is any one of the first to seventh exhaust gas treatment devices, In the second central axis direction in which the central axis of the second region extends, the distance between the first plate portion and the second plate portion is 6.3×10 with respect to the cross-sectional area of ​​the second region perpendicular to the second central axis direction. -5 ~14.2×10 -5 is within the range. A ninth exhaust gas treatment device according to the first invention is any one of the first to eighth exhaust gas treatment devices, In the second central axis direction in which the central axis of the second region extends, the distance between the second plate portion and the second catalyst portion is 5.4×10 with respect to a cross-sectional area of ​​the second region perpendicular to the second central axis direction. -5 ~15.7×10 -5 is within the range.

[0052] A tenth exhaust gas treatment device according to the first invention is any one of the first to ninth exhaust gas treatment devices, the second discharge portion includes two second pipes spaced apart in the first direction, each second pipe having a plurality of second discharge holes formed therein and spaced apart in the second direction; The center-to-center distance between the two second pipes is within a range of 14 to 65% of the distance between the second regions in the first direction. An eleventh exhaust gas treatment device according to the first invention is any one of the first to tenth exhaust gas treatment devices, The center-to-center distance of the second discharge holes of the second pipe is within a range of 3 to 5% of the distance of the second region in the second direction. A twelfth exhaust gas treatment device according to the first invention is any one of the first to eleventh exhaust gas treatment devices, the cylindrical body has a first cylindrical portion that forms the first region, A part or the whole of the first cylindrical portion is cylindrical, the first discharge portion includes a first pipe having a plurality of first discharge holes formed therein; The center-to-center distance between the first discharge holes of the first pipe is within a range of 5 to 15% of the diameter of the first cylindrical portion. A thirteenth exhaust gas treatment device according to the first invention is any one of the first to twelfth exhaust gas treatment devices, the cylindrical body has a first cylindrical portion that forms the first region, The swirling section includes a static mixer made up of a plurality of swirling blades fixedly arranged radially from a first central axis of the first cylindrical section. A fourteenth exhaust gas treatment device according to the first invention is any one of the first to thirteenth exhaust gas treatment devices, The static mixer is of the paddle type. A fifteenth exhaust gas treatment device according to the first invention is any one of the first to fourteenth exhaust gas treatment devices, The number of the swirler blades is four. A sixteenth exhaust gas treatment device according to the first invention is any one of the first to fifteenth exhaust gas treatment devices, The angle of the swirler is within a range of 28 to 55 degrees relative to the first central axis.

[0053] A seventeenth exhaust gas treatment device according to the first invention is any one of the first to sixteenth exhaust gas treatment devices, The width of the swirler vanes is within a range of 20 to 39% of the diameter of the first cylindrical portion. An eighteenth exhaust gas treatment device according to the first invention is any one of the first to seventeenth exhaust gas treatment devices, The cylindrical body has a first cylindrical portion that forms the first region and a second cylindrical portion that forms the second region. a cross-sectional shape of the second cylindrical portion is a rectangle that is long in a second direction perpendicular to the first direction and the central axis of the second region, or a shape similar to the rectangle; The cross-sectional shape of the first cylindrical portion is circular or similar to a circular shape.

[0054] 2. Invention 2 In the fluid mixing device of Patent Document 2, a fluid containing a different type of gas or liquid injected from a nozzle is dispersed and supplied to a catalyst pack, but there is a demand for more uniform dispersion and supply grade. An object of the present invention 2 is to provide a fluid supply device that can supply injected gas or liquid in a dispersed manner. The fluid supply device according to the second aspect of the present invention is a cylindrical portion having an inlet through which a fluid flows and an outlet through which the fluid that has flowed in from the inlet flows out, The cylindrical portion includes a discharge portion for discharging gas or liquid, and a swirling portion for swirling the fluid that has flowed into the cylindrical portion. An example of the "tubular portion" and the "discharge portion" is the "first cylindrical portion" and the "first discharge portion," and the outlet corresponds to the opening upstream of the first catalyst portion in the embodiment. The fluid is supplied to the processing portion, and an example of the processing portion is the first catalyst portion. According to the fluid supply device of the second aspect of the present invention, it is possible to supply a fluid in which the discharged gas or liquid is dispersed.

[0055] 3. Invention 3 In the fluid mixing device of Patent Document 2, a fluid containing a different type of gas or liquid injected from a nozzle is dispersed and supplied to a catalyst pack, but there is a demand for more uniform dispersion and classification. An object of the present invention 3 is to provide a fluid supply device that can supply injected gas or liquid in a dispersed manner. The fluid supply device according to the third aspect of the present invention comprises: a cylindrical portion having an inlet through which a fluid flows and an outlet through which the fluid that has flowed in from the inlet flows out, The cylindrical portion includes a second discharge portion for discharging gas or liquid, a first plate portion disposed on the outlet side of the second discharge portion, and a second plate portion disposed on the outlet side of the first plate portion. the first plate portion and the second plate portion are perpendicular to the central axis of the cylindrical body, First openings are formed on both end sides of the first plate portion in a first direction perpendicular to the central axis, The second plate portion has a second opening smaller than the first plate portion and between the first openings on both sides in the first direction. An example of the "tubular portion" and the "discharge portion" is the "second cylindrical portion" and the "second discharge portion," and the inlet corresponds to the inlet of the second region in the embodiment. The fluid is supplied to the treatment portion, and an example of the treatment portion is the second catalyst portion. According to the fluid supply device of the third aspect of the present invention, it is possible to supply a fluid in which the discharged gas or liquid is dispersed.

[0056] 4.Other Invention 2 may or may not have some or all of the invention-specific features of each of the twelfth to seventeenth exhaust gas treatment devices of the first invention, and may or may not have modified configurations. Invention 3 may or may not have some or all of the invention-specifying features of each of the second to eleventh exhaust gas treatment devices of the first invention, and may or may not have the configuration of a modified example. [Explanation of symbols]

[0057] 3 Denitration equipment 5 cylinder 51 First area 53 Second area 511 1st discharge part 513 Swivel section 515 1st catalyst section 531 2nd discharge part 533 1st plate part 535 2nd plate part 537 Second catalyst section

Claims

1. An exhaust gas treatment device used for exhaust gas that is emitted from an internal combustion engine and contains NOx, a cylindrical body having an inlet through which the exhaust gas flows and an outlet through which the exhaust gas that has flowed in from the inlet flows out, the cylindrical body has a first region and a second region in this order from the inlet side between the inlet side and the outlet side, the first region is provided with a first discharge portion for discharging a reducing agent, a swirling portion for swirling the exhaust gas that has flowed into the first region, and a first catalyst portion disposed on the second region side with respect to the first discharge portion and the swirling portion, The second region is provided with a second discharge portion having one or more second discharge holes for discharging the reducing agent, a first plate portion disposed on the outlet side of the second discharge portion, a second plate portion disposed on the outlet side of the first plate portion, and a second catalyst portion disposed on the outlet side of the second plate portion, the first plate portion and the second plate portion are perpendicular to the central axis of the second region, First openings are formed on both end sides of the first plate portion in a first direction perpendicular to the central axis, The second plate portion has a second opening smaller than the first plate portion between the first openings on both sides in the first direction. Exhaust gas treatment device.

2. a total opening area of ​​the first openings on both sides in the first direction is within a range of 10 to 30% of a cross-sectional area of ​​the second region; The exhaust gas treatment device according to claim 1 .

3. The opening area of ​​the second opening is within a range of 6 to 20% of the cross-sectional area of ​​the second region. The exhaust gas treatment device according to claim 2 .

4. When the second region is projected from the inlet side toward the outlet side, the second opening is located within an outer peripheral edge of the first plate portion. The exhaust gas treatment device according to claim 1 or 3.

5. When the second region is projected from the inlet side toward the outlet side, the area of ​​the portion where the first plate portion and the second plate portion overlap is within a range of 50 to 84% of the cross-sectional area of ​​the second region. The exhaust gas treatment device according to claim 1 or 4.

6. the cylindrical body has a second cylindrical portion that forms the second region, the second cylindrical portion has a rectangular shape or a shape similar to the rectangular shape that is long in a second direction perpendicular to the first direction and the central axis of the second region, The first opening and the second opening have a rectangular shape that is long in the second direction or a shape similar to the rectangular shape. The exhaust gas treatment device according to claim 1, 4 or 5.

7. In a second central axis direction in which the central axis of the second region extends, the distance from the entrance of the second region to the first plate portion is 3.0 × 10 with respect to a cross-sectional area of ​​the second region perpendicular to the second central axis direction. －５ ~15.1 x 10 －５ is within the range of The exhaust gas treatment device according to claim 1 or 6.

8. In the second central axis direction in which the central axis of the second region extends, the distance between the first plate portion and the second plate portion is 6.3×10 with respect to a cross-sectional area of ​​the second region perpendicular to the second central axis direction. －５ ~14.2 x 10 －５ is within the range of The exhaust gas treatment device according to claim 7 .

9. In the second central axis direction in which the central axis of the second region extends, the distance between the second plate portion and the second catalyst portion is 5.4 × 10 with respect to a cross-sectional area of ​​the second region perpendicular to the second central axis direction. －５ ~15.7 x 10 －５ is within the range of The exhaust gas treatment device according to claim 8 .

10. the second discharge portion includes two second pipes spaced apart in the first direction, each second pipe having a plurality of second discharge holes formed therein and spaced apart in the second direction; The center-to-center distance of the two second pipes is within a range of 14 to 65% of the distance in the first direction of the second region. The exhaust gas treatment device according to any one of claims 1, 6 and 9.

11. The center-to-center distance of the second discharge holes of the second pipe is within a range of 3 to 5% of the distance of the second region in the second direction. The exhaust gas treatment device according to claim 10.

12. the cylindrical body has a first cylindrical portion that forms the first region, A part or the whole of the first cylindrical portion is cylindrical, the first discharge portion includes a first pipe having a plurality of first discharge holes formed therein; The center-to-center distance of the first discharge holes of the first pipe is within a range of 5 to 15% of the diameter of the first cylindrical portion. The exhaust gas treatment device according to claim 1 .

13. the cylindrical body has a first cylindrical portion that forms the first region, the swirling section includes a static mixer including a plurality of swirling blades fixedly arranged radially from a first central axis of the first cylindrical section, The exhaust gas treatment device according to claim 1 .

14. The static mixer is a paddle type. The exhaust gas treatment device according to claim 13.

15. The number of the swirler vanes is four. The exhaust gas treatment device according to claim 13 or 14.

16. The angle of the swirler is within a range of 28 to 55 degrees with respect to the first central axis. The exhaust gas treatment device according to claim 15.

17. The width of the swirler is within the range of 20 to 38% of the diameter of the first cylindrical portion. The exhaust gas treatment device according to claim 13.

18. The cylindrical body has a first cylindrical portion that forms the first region and a second cylindrical portion that forms the second region. a cross-sectional shape of the second cylindrical portion is a rectangle that is long in a second direction perpendicular to the first direction and the central axis of the second region, or a shape similar to the rectangle; The cross-sectional shape of the first cylindrical portion is circular or similar to a circular shape. The exhaust gas treatment device according to claim 1 .

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