JP4490155B2 - Nitrogen oxide removal equipment - Google Patents

Description

  The present invention relates to a technique for removing nitrogen oxides from a mixed gas generated in an automobile tunnel, an automobile underpass, an indoor parking lot, or the like.

  Conventionally, in exhausting automobile tunnels and the like, for the purpose of reducing pollution, it has been studied to remove nitrogen oxides in exhaust gas and release it to the atmosphere. As a means for that, development of an apparatus for adsorbing and removing the nitrogen oxides with an adsorbent is in progress.

  Specifically, the following Patent Document 1 discloses one having an adsorbent packed layer filled with an adsorbent for adsorbing and removing nitrogen oxides in the middle of a gas passage through which a mixed gas to be processed flows. Has been.

  However, this apparatus has a disadvantage that it is not easy to carry the adsorbent and replace it on site. This inconvenience becomes more pronounced as the amount of adsorbent used increases.

  Therefore, Patent Document 2 below discloses an apparatus for facilitating the replacement work of the adsorbent.

  This apparatus has a two-story structure having an adsorbent storage chamber and a gas distribution chamber above and below. The floor of the adsorbent storage chamber is provided with a plurality of gas introduction ports that open to the gas distribution chamber below the adsorbent storage chamber, and an adsorbent cartridge is placed on the floor so as to cover each gas introduction port. Has been. Each adsorbent cartridge has a top wall and a side wall, but has a shape opened downward, and the side wall is composed of an adsorbent layer.

In this apparatus, when a mixed gas is introduced into the gas distribution chamber, the mixed gas flows into the adsorbent cartridge through the gas inlets, and then passes through the adsorbent layer to enter the adsorbent storage chamber. It flows out and is discharged from the adsorbent storage chamber to a predetermined place. At this time, when the mixed gas permeates through the adsorbent layer, nitrogen oxides contained in the mixed gas are adsorbed and removed by the adsorbent, so that only the remaining processed gas flows to the adsorbent storage chamber. It flows out and is discharged out of the system from the same room.
JP-A-11-333249 (0002, FIG. 2) JP 2001-79341 A (0031-0035, FIG. 3)

  In the apparatus described in Patent Document 2, the use of the adsorbent cartridge greatly facilitates the replacement work of the adsorbent compared to the apparatus described in Patent Document 1, but the cartridge is accommodated. Since the adsorbent storage chamber and the gas distribution chamber have a two-storied structure in which the adsorbent storage chamber and the gas distribution chamber are arranged vertically, there is a problem that it is difficult to keep the overall height of the apparatus small.

Further, regarding the flow of the mixed gas, since the mixed gas is introduced laterally with respect to the gas distribution chamber and then flows upward into the adsorbent storage chamber on the upper side, the mixed gas is simply placed in a substantially horizontal direction. Since the gas flow is more complicated than that of the flowing apparatus and it is difficult to ensure a large flow path area at the gas distribution chamber inlet, there is a problem that the pressure loss tends to increase as a whole. In particular, when a relatively large machine such as a silencer is installed on the downstream side of the adsorbent storage chamber, the machine must be installed on the side of the silencer because of its installation space. As a result, the mixed gas in the adsorbent storage chamber must be discharged to the side, further complicating the gas flow.

  In view of such circumstances, the present invention is a device for removing nitrogen oxides in a mixed gas, and processes the mixed gas in a substantially horizontal direction while facilitating the transporting and exchanging operations of the adsorbent. An object of the present invention is to reduce the height and pressure loss of the entire apparatus.

As means for solving the above problems, the present invention is a nitrogen oxide removing apparatus that adsorbs and removes nitrogen oxides contained in the mixed gas with an adsorbent while circulating the mixed gas in a substantially horizontal direction , A gas introduction part into which the mixed gas is introduced; a nitrogen oxide adsorption part that adsorbs and removes nitrogen oxides contained in the mixed gas while circulating the mixed gas introduced into the gas introduction part in a substantially horizontal direction; A gas outlet from which the mixed gas is led out from the nitrogen oxide adsorbing portion is arranged in a substantially horizontal direction, and the nitrogen oxide adsorbing portion includes a plurality of nitrogen oxide removing device adsorption units, each adsorption unit, respectively, shaped to form the inner flow path extending in a substantially horizontal direction inside, at least in part on the gas mixture and the adsorption member containing permeable adsorbent layer in the thickness direction It is arranged so as to surround the suction member from the outside, an outer frame which is formed in a cylindrical shape having a rectangular cross-section to form the outer flow path between the outer surface of the suction member, the inside of the outer frame A support member that supports the adsorbing member, and the inner flow path is opened and the outer flow path is closed at one axial end, and the inner flow path is closed and the outer flow path is closed at the other axial end. So that the mixed gas introduced from one of the opening of the inner flow path and the opening of the outer flow path passes through the adsorbent layer and is discharged from the other opening. One of the opening of the inner flow path and the opening of the outer flow path in each adsorption unit faces the gas introduction part, and the other opening faces the gas lead-out part. The outer faces of the outer frame are in a posture where the units are parallel to each other The adsorption unit with each other by being superimposed are arranged in a matrix, in which the outer frame of each adsorption unit in this arrangement state to secure the outer flow path between the outer surface of the suction member.

  In this apparatus, the mixed gas introduced into the gas introduction unit is provided with an inner flow path of each adsorption unit for nitrogen oxide removing devices (hereinafter simply referred to as “adsorption unit”) arranged in the nitrogen oxide adsorption unit. Of the outer channel, the gas flows into the channel opened to the gas introduction unit side, passes through the adsorbent layer of the adsorption member facing the channel, and opens to the gas outlet unit side. And flows out from this flow path to the gas outlet. At this time, when the mixed gas permeates the adsorbent layer, nitrogen oxides contained in the mixed gas are adsorbed and removed by the adsorbent, so that only the remaining processed gas is transferred to the adsorbent storage chamber. It flows out and is discharged out of the system from the same room.

  Therefore, in this apparatus, the mixed gas can be processed while flowing in a substantially horizontal direction in the order of the gas introduction part, the nitrogen oxide adsorption part, and the gas outlet part, thereby reducing the overall height of the apparatus and reducing the pressure loss. Can be reduced. In particular, the gas introduction part, such as the one where the gas introduction part is provided with an electric dust collector for removing suspended particulate matter in the mixed gas introduced into the gas introduction part, or the one where the silencer is provided in the gas outlet part When a relatively large machine is installed in the gas outlet part, the machine can be arranged at substantially the same height level as the nitrogen oxide adsorbing part, which is extremely advantageous in terms of the apparatus layout.

  Moreover, each of the adsorption units has an outer frame on the outer side of the adsorption member having the adsorbent layer, and not only the inner flow path in the adsorption member but also the outer flow path between the adsorption member and the outer frame. These adsorbing units are arranged vertically and horizontally in a so-called horizontal state (in which the axial direction is substantially horizontal), but in each adsorbing unit, the adsorbing unit is located upstream of the adsorbent layer. Both the flow path and the downstream flow path can be reliably formed.

  In addition, since a plurality of suction units are used in combination, it is possible to flexibly cope with changes in the air volume and installation space by changing the number of arrays (number of columns and stages). Furthermore, a larger adsorbent layer surface area can be secured in the same installation space as compared to the case where a single adsorbent layer is used.

  When arranging the adsorption units vertically and horizontally, a sealing material such as a rubber sheet may be interposed between the units to prevent the mixed gas from flowing.

  In the present invention, the specific shape of each suction unit is not particularly limited. However, if the outer frame is a suction unit formed in a cylindrical shape having a rectangular cross section, the outer surfaces of the outer frames are brought into contact with each other. However, these adsorption units can be arranged in an orderly manner.

  In particular, in the suction unit in which the outer frame is formed in a cylindrical shape having a square cross section, it can be arranged regardless of the vertical and horizontal directions, and thus the arrangement work becomes easier.

  The adsorbing member only needs to have the adsorbent layer in a part thereof, but if substantially the entire adsorbing member is constituted by the adsorbent layer, the processing efficiency is further improved.

  In that case, although the said adsorbent layer may be comprised by the single thing, if the said adsorbent layer is divided | segmented into multiple at least in the circumferential direction of the said adsorption member, it adsorb | sucks in the division | segmentation state The agent layer can be transported at a lower cost.

  In particular, if the adsorbing member has a shape having a polygonal cross section (including a triangle or a quadrangle) and the side walls constituting the respective sides are each constituted by the adsorbent layer, each adsorbed divided Since the agent layer has a flat plate shape, the conveyance of the agent layer is further facilitated.

  The support member may be any member as long as it supports the adsorbing member in the outer frame. Further, at least the adsorbent layer of the adsorbing member is inserted into and removed from the inner space of the outer frame in the axial direction. It is more preferable to support the adsorbing member so that it is possible. According to this configuration, it is possible to replace the adsorbent layer while leaving the outer frame, which is more economical than the case where the entire adsorption unit including the outer frame is replaced.

  In particular, the support member includes a traveling body that is fixed to one member of the adsorption member and the outer frame and that can travel in the axial direction with respect to the surface of the other member. If it is a thing, the insertion / extraction operation | work of the adsorption | suction member with respect to the inside of an outer frame can be made smoother.

  The support member may be fixed to either the suction member or the outer frame, but if the support member is fixed to the outer frame side, the common support member is continuously used even if the suction member is replaced. Is possible and will be more economical.

  Since this adsorbing unit is such that the mixed gas permeates the adsorbent layer in a direction substantially orthogonal to the flow direction in the inner flow path or the outer flow path, the transmittance is the above-mentioned among the inner flow path and the outer flow path. Although it is easy to concentrate on the downstream portion of the upstream flow channel, which is the flow channel upstream of the adsorbent layer, the mixed gas flows through the upstream flow channel in the middle of the upstream flow channel. By adopting a configuration in which a gas guide member that guides the adsorbent layer in the direction of transmission is provided, the permeability of the mixed gas to the adsorbent layer can be made uniform in the axial direction.

  In particular, if the gas guide members are arranged at a plurality of positions aligned in the axial direction of the upstream flow path, it is possible to further promote the uniformity of the transmittance. Here, the gas flow rate at the inlet portion in the upstream channel is likely to be larger than the gas flow rate at the downstream portion, and pressure loss is likely to occur, but at the position where each gas guide member is disposed. If the shape of each gas guide member is set such that the flow passage area excluding the gas guide member becomes smaller as the downstream gas guide member is disposed, the arrangement of each gas guide member is set. By securing a flow path area corresponding to the gas flow rate at the position at the position, an increase in pressure loss can be effectively suppressed.

  Further, in view of the tendency of the gas flow rate, the flow area of the upstream flow path, which is the flow path upstream of the adsorbent layer, of the inner flow path and the outer flow path becomes smaller toward the downstream side. And the shape of both flow paths is such that the flow area of the downstream flow path, which is the flow path downstream of the adsorbent layer, of the inner flow path and the outer flow path becomes larger toward the downstream side. Is set, the gas flow rate can be made uniform and pressure loss can be suppressed.

  As described above, according to the present invention, by configuring the nitrogen oxide adsorbing unit with a plurality of units, it is possible to flow and process the mixed gas in a substantially horizontal direction while facilitating the transporting and replacing work of the adsorbent. This makes it possible to reduce the overall height of the apparatus and reduce pressure loss.

  A preferred embodiment of the present invention will be described with reference to the drawings.

  The nitrogen oxide removing apparatus shown in FIGS. 1 and 2 is constructed, for example, in a concrete structure for tunnel formation buried underground, and includes a gas introduction unit 10, a nitrogen oxide adsorption unit 12, and a gas The derivation | leading-out part 14 is provided, and each part 10,12,14 is arranged in the horizontal direction in that order.

  A mixed gas containing automobile exhaust gas generated in the tunnel or the like is introduced into the gas introduction unit 10 through a passage not shown. An electric dust collector 16 that removes suspended particulate matter in the mixed gas is provided in the gas introduction unit 10.

  A plurality of adsorption units 20 are loaded in the nitrogen oxide adsorption unit 12. These adsorbing units 20 adsorb and remove nitrogen oxides in the mixed gas while flowing the mixed gas sent from the gas introducing unit 10 in a substantially horizontal direction, and the treated gas is discharged into the gas deriving unit 14. It is what will be drained. In the illustrated example, nine suction units 20 are installed in a 3 × 3 array in a posture parallel to each other.

  The gas deriving unit 14 receives the treated gas sent from the nitrogen oxide adsorbing unit 12, guides it to an appropriate part, and releases it to the atmosphere. In the gas deriving unit 14, a silencer 18 is provided. Is provided.

  Next, various structural examples of the adsorption unit 20 loaded in the nitrogen oxide adsorption unit 12 will be described. Any of the adsorption units 20 shown below exhibits an excellent adsorption effect when installed in the nitrogen oxide adsorption unit 12 in an appropriate arrangement.

  The adsorption unit 20 shown in FIGS. 3A and 3B has a double structure in which an outer frame 24 is provided outside the adsorption member 22, and a support member 34 is provided between the adsorption member 22 and the outer frame 24. Is intervening.

  The adsorbing member 22 includes four adsorbing panels 26 constituted by adsorbent layers, and four corner bars (corner members) 28 interposed between the adsorbing panels 26. The adsorbing member 22 has a cylindrical shape with a square cross section cut in a plane orthogonal to the axial direction (left-right direction in FIG. 3B), and an inner flow path 30 is formed on the inside thereof. . And the site | part corresponded to each side of the said square is comprised by the said adsorption | suction panel 26, the site | part corresponded to each vertex part of the said square is comprised by the said corner | angular material 28, and the both ends of each adsorption | suction panel 26 are The corner square member 28 is fixed to two inner side surfaces of the four side surfaces. That is, the substantially entire surface of the adsorbing member 22 (the surface excluding the corner square member 28) is composed of an adsorbent layer, and the adsorbent layer is divided into four adsorbing panels 26. Yes.

The adsorbent layer constituting the adsorption panel 26 contains an adsorbent that adsorbs and removes nitrogen oxides. Specifically, NO (nitrogen monoxide) is oxidized or the oxidation reaction is promoted to reduce NO2 (
Nitrogen dioxide) and the ability to adsorb NO and NO2 to some extent,
And those capable of adsorbing NO2 and reducing NO2 to NO (for example, carbonaceous materials), or those using these in combination are suitable. These adsorbents can be held by being sandwiched between a net (for example, a metal net) having a finer eye than the adsorbent or a lattice (for example, a molded product made of metal, plastic, etc.) When laminating a plurality of adsorbent layers, a similar network or lattice may be interposed between the adsorbent layers.

  The outer frame 24 is formed of a material having a relatively high strength such as a metal material, has a cylindrical shape surrounding the outside of the adsorption member 22, and an outer flow path 32 between the outside surface of the adsorption member 22. Is forming. In the illustrated example, like the suction member 22, a cross section cut by a plane orthogonal to the axial direction (the left-right direction in FIG. 3B) forms a square.

  The support member 34 is disposed in a plurality of positions aligned in the axial direction in the outer flow path 32, and connects the corner square 28 in the adsorption member 22 and the side wall of the outer frame 24 adjacent thereto. The adsorbing member 22 is supported at an appropriate position in the outer frame 24 (in the illustrated example, the position where the central axis of the outer frame 24 and the central axis of the adsorbing member 22 match).

  At the shaft end on the inlet side of the adsorption unit 20 (the left shaft end in FIG. 3B), the outer flow path 32 is blocked by the lid 36 to prevent the gas from flowing. 30 is opened to the side to form a gas inlet 38. On the other hand, at the shaft end on the outlet side of the adsorption unit 20 (the shaft end on the right side in FIG. 3B), the inner flow path 30 is blocked by the lid 40 and the gas flow is prevented. The outer flow path 32 opens laterally to form a gas outlet 42. And each adsorption unit 20 is arrange | positioned in the said nitrogen oxide adsorption part 12 so that the said gas inlet_port | entrance may face the said gas introduction part 10 side, and the said gas outlet 42 may face the said gas derivation | leading-out part 14 side.

  In such an arrangement state, the mixed gas introduced into the gas introduction unit 10 flows into the inner flow path 30 through the gas inlet 38, and each of the adsorption panels 26 constituting the adsorption member 22 is formed from the inner flow path 30. It passes through the adsorbent layer and flows out to the outer channel 32, and is led out from the outer channel 32 to the gas outlet 14 through the gas outlet 42. At this time, when the mixed gas permeates through the adsorbent layer, nitrogen oxides contained in the mixed gas are adsorbed and removed by the adsorbent layer, so that the treated mixed gas flows out to the outer flow path 32. Will do.

That is, in the adsorption unit 20, the mixed gas can be processed while flowing in a substantially horizontal direction, and the inner flow path 30 constitutes an upstream flow path upstream of the adsorbent layer. And the outer side flow path 32 comprises the downstream flow path downstream from the said adsorbent layer. These flow paths are reliably maintained by the strength of the outer frame 24 even if the adsorption units 20 are stacked in a plurality of stages.

  4 (a) and 4 (b) show an example of the adsorption unit 20 in which the outer channel 32 constitutes an upstream channel and the inner channel 30 constitutes a downstream channel contrary to the above. It is. Specifically, at the shaft end on the inlet side of the suction unit 20 (the shaft end on the left side in FIG. 4B), the inner flow path 30 is blocked by the lid 40, while the outer flow path 32 is lateral. A gas inlet 38 is formed in the opening. On the other hand, at the shaft end on the outlet side (the right shaft end in FIG. 4B), the outer flow path 32 is blocked by the lid 36, while the inner flow path 30 opens sideways. A gas outlet 42 is formed. The adsorption unit 20 is also disposed in the nitrogen oxide adsorbing section 12 such that the gas inlet 38 faces the gas introduction section 10 and the gas outlet 42 faces the gas outlet section 14.

  Regarding the proper use of the adsorption unit 20 shown in FIGS. 4 (a) and 4 (b) and the adsorption unit 20 shown in FIGS. 3 (a) and 3 (b), the installation space and structure of the entire nitrogen oxide removing device, etc. It may be determined appropriately according to the situation.

  In the suction unit 20, the suction member 22 may be completely fixed inside the outer frame 24, but the suction member 22 can be inserted and removed in the axial direction with respect to the inner side of the outer frame 24. If comprised in this way, it will become possible to replace | exchange only the adsorption | suction member 22 leaving the outer frame 24, and it will become more economical. For this purpose, for example, in the suction unit 20 shown in FIGS. 3A and 3B, the support member 34 is fixed to only one of the suction member 22 and the outer frame 24, and the other is fixed to the other. What is necessary is just to comprise so that a slide is possible.

  5 (a) and 5 (b) show that the suction member 22 is inserted into and removed from the outer frame 24 instead of the lower support member 34 of the support members 34 shown in FIGS. 3 (a) and 3 (b). The structure provided with the conveyor 44 which makes smoother as a supporting member is shown.

  The conveyor 44 includes a plurality of brackets 46 and rollers 48 supported by the brackets 46. Each bracket 46 is erected at a plurality of positions aligned in the axial direction on the inner side surface of the bottom wall of the outer frame 24, and the upper end of the bracket 46 is in a direction perpendicular to the axial direction at the same height position ( In the illustrated example, it is held so as to be rotatable about the axis in the left-right direction in FIG.

  According to this structure, the suction member 22 is smoothly inserted into and removed from the outer frame 24 while the rollers 48 of the conveyor 44 are rotated, and the suction member 22 is properly moved by the conveyor 44 when the insertion is completed. Supported in position.

  The said conveyor 44 may be provided in the adsorption | suction member 22 side, as shown to Fig.6 (a) (b). In the illustrated example, a bracket 46 projects downward from the lower surface of the lower left and right corner bars 28 of the suction member 22, and a roller 48 is rotatably held at the lower end of each bracket 46. Also in this structure, each of the rollers 48 rolls on the inner side surface of the bottom wall of the outer frame 24 so that the adsorption member 22 can be smoothly inserted into and removed from the outer frame 24.

  As described above, the support member may be fixed to either the adsorption member 22 or the outer frame 24, but the support member is fixed to the outer frame 24 and separated from at least the adsorbent layer of the adsorption member 22. If it is a structure, it can be used continuously with the outer frame 24 regardless of the exchange of the adsorbent layer, and it becomes more economical.

  Further, even if slide support means such as a slide rail is used instead of the conveyor as described above, it is possible to smoothly insert and remove the adsorbing member 22.

  Furthermore, FIG. 7 shows that only the suction panel 26 can be individually inserted into and removed from the outer frame 24 among the four suction panels 26 and the four corner bars 28 constituting the suction member 22. The configured adsorption unit 20 is shown.

  In the suction unit 20, panel fitting portions 25 are fixed to two inner side surfaces of the four side surfaces of the corner square member 28. Each panel fitting portion 25 has a U-shaped cross section that sandwiches the edge portion of the suction panel 26 adjacent to each corner square member 28 from both the inside and outside, and the suction panel 26 is disposed inside the panel fitting portion 25. The suction panel 26 can be attached and detached by inserting the edge portions of the suction panel 26.

  As described above, if the adsorbent layer constituting one adsorbing member 22 is divided into a plurality of adsorbing panels 26, the adsorbent layer can be more easily transported, further reducing the cost during transport. It is advanced. In particular, as shown in the drawing, if each suction panel 26 can be inserted and removed individually, it is possible to continue using not only the outer frame 24 but also the corner square 28 even if the suction panel 26 is replaced. It becomes more economical.

  This structure can also be applied when the adsorbing member 22 has a polygon other than a quadrangle (including a triangle) and other cross-sectional shapes, and in either case, the adsorbent layer of the adsorbing member 22 is divided in the circumferential direction. You just have to do it.

  By the way, in the adsorption unit 20 shown in FIGS. 3A and 3B, the mixed gas permeates the adsorbent layer in a direction substantially perpendicular to the flow direction in the inner flow path 30 that is the upstream flow path. The transmittance tends to concentrate on the downstream portion of the inner flow path 30. Therefore, in the adsorption unit 20 shown in FIGS. 8 (a) and 8 (b), the gas guide member 50 for guiding the mixed gas flowing through the inner flow path 30 to the terminal portion and the middle portion of the inner flow path 30 in the permeation direction. 52, 54, and 56 are provided.

  The gas guide member 50 is provided so as to overlap the lid 40 at the end of the inner flow path, and has a quadrangular pyramid-shaped guide surface that guides the incoming mixed gas to the outside in the radial direction.

  The gas guide members 52, 54, 56 are provided in the middle of the inner passage 30, and are arranged in the order of the gas guide members 52, 54, 56 from the side close to the gas guide member 50.

  Each gas guide member 52, 54, 56 has an opening so that the central portion 52b, 54b, 56b protrudes toward the gas upstream side (left side in FIG. 8B) and the mixed gas can flow. Gas guide surfaces 52a, 54a, and 56a are formed around the central portions 52b, 54b, and 56b, respectively. These gas guide surfaces 52a, 54a, and 56a are smooth curved surfaces that are configured to guide the mixed gas in the permeation direction from the central portions 52b, 54b, and 56b toward the adsorbent layer in the radially outer adsorbing member 22. It is made up of.

  Further, in view of the fact that the gas flow rate decreases toward the downstream side of the inner flow path 30, regarding the size of the opening of each central portion 52b, 54b, 56b, the opening area of the central portion 56b> the opening area of the central portion 54b > The opening area of the central portion 52b is set. That is, consideration is given so that the flow path area excluding the gas guide member (that is, the opening area of the central portion) becomes larger as the gas guide member is disposed on the downstream side.

As shown in FIG. 4B, this gas guide member is also applied to the adsorption unit 20 in which the outer channel 32 constitutes an upstream channel and the inner channel 30 constitutes a downstream channel. Is possible. An example is shown in FIGS. 9 (a) and 9 (b).

  In the figure, gas guide members 60, 62, 64, 66 are provided in order from the downstream side at the terminal portion and the middle portion of the outer flow channel 32 that is the upstream flow channel.

  The gas guide member 60 is provided so as to overlap the lid 36 at the end of the outer flow path, and has a tapered guide surface that guides the incoming mixed gas to the inside in the radial direction.

  Each gas guide member 62, 64, 66 is fixed to the adsorbing member 22 so as to protrude radially outward from the outer peripheral surface of the adsorbing member 22, and the mixed gas arriving from the gas inlet 38 is passed through the adsorbent layer. Gas guide surfaces 62a, 64a and 66b each having a shape for guiding in the transmission direction are provided.

  The projection amount of each gas guide member from the adsorption member 22 is set so that the projection amount of the gas guide member 62> the projection amount of the gas guide member 64> the projection amount of the gas guide member 66, The area of the flow path that is left outside the gas guide member becomes larger as the gas guide member on the side is disposed.

  10 (a) and 10 (b) show the distribution of the gas flow rate in the upstream flow channel as described above, that is, the flow channel area of the upstream flow channel in view of the distribution in which the gas flow rate decreases toward the downstream side. The flow path area of the downstream flow path, which is the flow path downstream of the adsorbent layer among the inner flow path and the outer flow path, becomes smaller toward the downstream side, and becomes larger as it goes downstream. The example of the adsorption | suction unit 20 by which the shape of both flow paths was set so that it may become is shown.

  Specifically, in the suction unit 20 in the figure, the outer frame 24 is parallel to the axial direction of the unit, while the suction member 22 is given a slight taper angle θ. The flow path area of the inner flow path 30 that is the upstream flow path decreases toward the downstream side (the right side in FIG. 10) by this taper angle θ, and the outer flow path 32 that is the downstream flow path. The flow path area increases.

  According to such a structure, the pressure loss can be more effectively suppressed by making the gas flow rate uniform in the unit axial direction.

  The taper angle θ may be appropriately set in consideration of the magnitude relationship between the axial length and the cross-sectional area that can be taken in the suction unit 20, and is generally given in a range of less than 20 °, preferably less than 10 °. Good.

  In any of the adsorption units 20 shown above, the nitrogen oxidation of the nitrogen oxide removing apparatus shown in FIGS. 1 and 2 in a state where the adsorption unit 20 is in a horizontal state (a state in which the unit axial direction and the horizontal direction match). If it is arranged in the object adsorbing part 12 (the figure shows an example using the adsorbing unit 20 shown in FIGS. 3A and 3B), the gas introducing part 10 to the nitrogen oxide adsorbing part. The process can be performed while flowing the mixed gas in a substantially horizontal direction through 12 to the gas outlet 14, and the adsorbent can be transported or exchanged on site.

  Note that when the adsorption units 20 are arranged, a sealing material such as a rubber sheet is sandwiched between the units 20 to prevent leakage of the mixed gas.

In the present invention, the gas introduction part 10, the nitrogen oxide adsorption part 12, and the gas lead-out part 14 do not necessarily have to be accurately arranged in the horizontal direction, and these may be arranged in a slightly inclined direction. In short, it is sufficient if the height of the entire apparatus can be effectively reduced and the flow of the mixed gas can be made simple and smooth. Similarly, each suction unit 20 may also be arranged slightly inclined.

  What is necessary is just to set the full length of the adsorption | suction unit 20 suitably within the given installation space. If the suction unit 20 is quite long and is not easy to handle (carrying in and out), it may be transported by dividing it in the axial direction and connected on site.

  In the present invention, the specific shape of the outer frame 24 can be set as appropriate. However, if the cross-sectional shape of the outer frame 24 is rectangular, the suction units 20 can be stably arranged in the vertical and horizontal directions while closely adhering the suction units 20 to each other. Arrangement work can be made easier because there is no need to consider the orientation.

  The shape of the suction member 22 can also be set as appropriate, and may be designed in consideration of the shape of the outer frame 24, the surface area required for the suction panel 26, and the like.

  FIG. 11A shows an adsorbing member comprising an adsorbing panel 26 having a thickness t in an outer frame 24 of a square cross section having a side length L under the condition that the inner channel area and the outer channel area are equal. The adsorption panel surface area A obtained when the cross-sectional shape of 22 is set to various shapes is shown. FIG. 5B is a graph showing the relationship between t / L and A / L in each embodiment. Is.

  As can be seen from the figure, those with a four-sided panel arrangement (four suction panels 26 arranged in a square shape) are those with a cylindrical panel arrangement (the suction panel 26 in a cylindrical shape regardless of t / L). A panel surface area larger than that of the arrangement) can be secured, and if t / L is about 0.25 or less, a two-panel arrangement (two suction panels 26 arranged in parallel) A larger panel surface area can be ensured.

  The following conditions are set for the suction unit 20 having the structure shown in FIGS.

・ Ventilation air volume: 320,000 Nm ³ / h
・ Arrangement and number of adsorption units: Vertical 3 × Horizontal 3 = 9 units ・ Outer frame cross-sectional shape: Square (1,600 mm × 1,600 mm)
・ Unit length: 5,500mm
・ Adsorption panel thickness: 125mm
・ Inclination angle of suction member with respect to unit axial direction: 0 °
Under this condition, the installation space of the entire apparatus is 126.7 m ³ . Further, by performing the flow analysis under the same conditions, a value of 32 mmAq was obtained for the pressure loss of the entire apparatus.

  The following conditions are set for the suction unit 20 having the structure shown in FIGS.

・ Ventilation air volume: 320,000Nm3 / h
・ Arrangement and number of adsorption units: Vertical 5 × Horizontal 5 = 25 units ・ Outer frame cross-sectional shape: Square (1,000 mm × 1,000 mm)
・ Unit length: 3,500mm
・ Adsorption panel thickness: 125mm
・ Inclination angle of suction member with respect to unit axial direction: 0 °
Under this condition, the installation space for the entire apparatus is 87.5 m 3. Further, by performing the flow analysis under the same conditions, a value of 33 mmAq was obtained for the pressure loss of the entire apparatus.

Incidentally, as a comparative example, the apparatus described in FIG. 1 of Patent Document 1 has the following conditions: Ventilation air volume: 320,000 Nm ³ / h
・ Arrangement and number of adsorption units: 1 unit ・ Outer frame cross-sectional shape: square (11,000 mm × 11,000 mm)
・ Required length in the adsorbent depth direction: 3,500 mm
・ Adsorption panel thickness: 125mm
・ Inclination angle of suction member with respect to unit axial direction: 35 °
Is set, the installation space is 919.6 m ³ , and the pressure loss is 30 mmAq. When this comparative example is compared with the examples 1 and 2, the pressure loss is almost the same, and the installation space is about 14% of the comparative example in Example 1 and about 10% of the comparative example in Example 2. It is possible to suppress to.

  In order to confirm the effects of the gas guide members 50, 52, 54, and 56 shown in FIGS. 8 (a) and 8 (b), the adsorption unit including the gas guide member as shown in FIGS. 8 (a) and 8 (b). (Hereinafter referred to as “unit with guide function”) and an adsorption unit (hereinafter referred to as “unit without guide function”) having no gas guide member as shown in FIGS. The following conditions were set and the flow analysis was performed.

・ Ventilation air volume: 10,800 Nm ³ / h
-Arrangement and number of adsorption units: 1 unit-Outer frame cross-sectional shape: Square (1,000 mm x 1,000 mm)
・ Unit length: 3,000mm
・ Adsorption panel thickness: 125mm
・ Inclination angle of suction member with respect to unit axial direction: 0 °
As a result, the pressure loss was 34 mmAq for the unit with the guide function and 31 mmAq for the unit without the guide function. Further, when the distribution of the gas permeation rate (that is, the adsorbent passage flow rate of the mixed gas) in the adsorbent layer in the unit axial direction is obtained, the unit without the guide function has a considerably large gradient as shown in FIG. Yes, there is a difference equivalent to ± 30% of the average flow rate between the minimum flow rate (permeation flow rate on the inlet side) and the maximum flow rate (permeation flow rate on the exit side) As shown in FIG. 5B, it was found that the flow velocity fluctuation can be suppressed to ± 20% or less of the average flow velocity value.

It is a cross-sectional side view which shows the whole structure of a nitrogen oxide removal apparatus. It is a cross-sectional front view of the said nitrogen oxide removal apparatus. (A) is a cross-sectional front view of the adsorption | suction unit in which an inner side flow path comprises an upstream flow path, (b) is the cross-sectional side view. (A) is a cross-sectional front view of the adsorption unit in which the outer flow path constitutes the upstream flow path, and (b) is a cross-sectional side view thereof. (A) is the cross-sectional front view of the adsorption | suction unit in which a part of supporting member was comprised with the conveyor, (b) is the cross-sectional side view. (A) is the cross-sectional front view of the adsorption | suction member with which the conveyor was attached to the lower surface, (b) is the cross-sectional side view. (A) is a sectional front view showing the state before the suction panel is inserted in the suction unit in which the suction panel is individually inserted and removed, and (b) shows the state after the suction panel is inserted into the suction unit. It is a cross-sectional front view. (A) is the cross-sectional front view of the adsorption | suction unit by which the gas guide member was attached to the adsorption | suction unit shown by the said FIG. 3 (a) (b), (b) is the cross-sectional side view. (A) is the cross-sectional front view of the adsorption | suction unit by which the gas guide member was attached to the adsorption | suction unit shown by the said FIG. 4 (a) (b), (b) is the cross-sectional side view. (A) is the cross-sectional front view of the adsorption | suction unit by which the taper angle was given to the adsorption | suction member of the adsorption | suction unit shown by said FIG. 3 (a) (b), (b) is the cross-sectional side view. (A) is a table showing the theoretical panel surface area when the cross-sectional shape of the adsorption member is set to various shapes, (b) is a correlation between the panel thickness and the panel surface area when the cross-sectional shape of the adsorption member is set to various shapes. It is a graph which shows. (A) is a graph showing the adsorbent permeation speed distribution in the axial direction of the unit without the guide function, and (b) is a graph showing the adsorbent permeation speed distribution in the axial direction of the unit without the guide function.

DESCRIPTION OF SYMBOLS 10 Gas introduction part 12 Nitrogen oxide adsorption part 14 Gas derivation | leading-out part 16 Electric dust collector 18 Silencer 20 Adsorption unit 22 Adsorption member 24 Outer frame 26 Adsorption panel 30 Inner flow path 32 Outer flow path 34 Support member 36, 40 Lid 38 Gas inlet 42 Gas outlet

Claims (13)

A nitrogen oxide removing device that adsorbs and removes nitrogen oxides contained in the mixed gas by an adsorbent while circulating the mixed gas in a substantially horizontal direction ,
A gas introduction part into which the mixed gas is introduced; a nitrogen oxide adsorption part that adsorbs and removes nitrogen oxides contained in the mixed gas while circulating the mixed gas introduced into the gas introduction part in a substantially horizontal direction; A gas lead-out part from which the mixed gas is led out from the nitrogen oxide adsorbing part is arranged side by side in a substantially horizontal direction,
The nitrogen oxide adsorbing portion includes a plurality of adsorption units for a nitrogen oxide removing device, and each adsorption unit has a shape that forms an inner flow path extending in a substantially horizontal direction, and at least a part thereof. It said mixed gas and a suction member including a permeable adsorbent layer in the thickness direction, are arranged so as to surround the suction member from the outside, rectangular and forming an outer flow path between the outer surface of the suction member An outer frame formed in a cylindrical shape having a cross section and a support member for supporting the adsorption member inside the outer frame, and the inner flow path is opened at one shaft end to block the outer flow path. The inner flow path is closed and the outer flow path is opened at the other shaft end, and is introduced from one of the opening of the inner flow path and the opening of the outer flow path. After the mixed gas permeates the adsorbent layer, the other gas is opened. It is configured to be discharged from,
One of the inner channel opening and the outer channel opening of each adsorption unit faces the gas introduction part, the other opening faces the gas outlet part, and these adsorption units are mutually connected. The suction units are arranged vertically and horizontally by overlapping the outer surfaces of the outer frames in a parallel posture, and the outer frames of the suction units are arranged between the outer surfaces of the suction members in this arrangement state. A nitrogen oxide removing apparatus characterized by securing a flow path . Oite nitrogen oxide removal equipment according to claim 1, the nitrogen oxide removal device, wherein a sealing member is interposed between the adsorption unit adjacent to each other. Oite to claim 2 nitrogen oxide removal equipment according, the outer frame is a nitrogen oxide removal device, characterized in that it is formed in a cylindrical shape having a square cross-section. Oite nitrogen oxide removal equipment according to claim 1, substantially nitrogen oxide removal equipment, characterized in that the entire surface is constituted by the adsorbent layer of said suction member. Oite nitrogen oxide removal equipment according to claim 4, wherein the nitrogen oxide removal device, characterized in that it is divided into a plurality in the circumferential direction of the adsorbent layer is at least the suction member. And characterized in that Oite nitrogen oxide removal equipment according to claim 5, wherein the suction member is a shape having a polygonal cross-section, side walls constituting the sides are constituted by each of the adsorbent layer nitrogen oxide removal equipment to. Oite nitrogen oxide removal equipment according to claim 1, wherein the support member is inserted into and removed axially at least adsorbent layer to the inner space of the outer frame of the suction member nitrogen oxide removal equipment, characterized in that for supporting the suction member so as to be. Oite nitrogen oxide removal equipment according to claim 7, wherein the nitrogen oxide removal equipment for the support member, characterized in that it is fixed to the outer frame side. Oite nitrogen oxide removal equipment according to claim 1, wherein the inner channel and the outer flow path upstream channel the on the upstream side of the flow path than the adsorbent layer of the middle moiety, the nitrogen oxide removal equipment, wherein a gas guide member for guiding the mixed gas flowing through the upstream flow path in a direction in which the gas mixture passes through the adsorbent layer is provided. Oite nitrogen oxide removal equipment according to claim 9, together with the gas guide member, respectively, are arranged in a plurality of positions aligned in the axial direction of the upstream passage, the arrangement position of each gas guide member nitrogen oxide removal equipment for flow area, excluding the gas guide member, characterized in that the shape of the gas guide member such as smaller at the arrangement position of the downstream side of the gas guide member is set. Oite nitrogen oxide removal equipment according to any one of claims 1 to 10, wherein the flow of the upstream side flow path on the upstream side of the flow path than the adsorbent layer of said inner channel and outer channel The channel area becomes smaller toward the downstream side, and the channel area of the downstream channel which is the channel downstream of the adsorbent layer among the inner channel and the outer channel is on the downstream side. nitrogen oxide removal equipment, characterized in that the shape of both flow paths is set to be larger toward. 12. The nitrogen oxide removing apparatus according to claim 11 , wherein the gas introduction part is provided with an electric dust collector for removing suspended particulate matter in the mixed gas introduced into the gas introduction part. Oxide removal equipment. The nitrogen oxide removing apparatus according to claim 11 or 12 , wherein a silencer is provided in the gas outlet part.

Images