JP5977055B2 - Gas rectifier and bag filter equipped with the gas rectifier - Google Patents

Description

  The present invention provides a connection between an upstream gas channel and a downstream gas channel having a larger channel cross-sectional area than the upstream gas channel and extending in a direction bent with respect to the upstream gas channel. The present invention relates to a gas rectifier used for adjusting the flow of gas to be circulated in the downstream gas flow path at a location, and a bag filter including the gas rectifier.

  In the treatment of combustion exhaust gas from a combustion furnace such as a garbage incinerator, a small dust such as fly ash that cannot be collected by a cyclone dust collector is collected using a bag filter.

  In the bag filter, a gas outlet is provided at one side of the upper end of a cylindrical container extending in the vertical direction, and a gas inlet is provided at a side of the lower end of the container. Further, a plurality of cylindrical bag-like filter cloths are attached between the gas inlet and the gas outlet in the container so as to be suspended from the cell plate.

  An inlet duct (upstream gas flow path) for introducing combustion exhaust gas into the container from the combustion furnace side is connected to the gas inlet of the container in the horizontal direction (lateral direction). Normally, the flow passage cross-sectional area of the inlet duct is smaller than the flow passage cross-sectional area in the container (downstream gas flow path).

  Therefore, in the bag filter, in the gas inlet portion of the cylindrical container, the combustion exhaust gas flowing through the upstream side inlet duct flows from the horizontal direction to the vertical direction with respect to the inside of the container having a larger flow path cross-sectional area. It bends in a substantially perpendicular direction and flows (see, for example, Patent Document 1).

  By the way, at the location where the downstream gas passage is connected to the upstream gas passage so that the gas flow is bent, for example, at a right angle, the downstream gas flow is more than the upstream gas passage. The gas flow flowing into the passage tends to go straight along the gas flow direction in the upstream gas flow path. Therefore, in the downstream side gas flow path, the gas flow tends to be uneven. Furthermore, when the downstream gas flow path has a larger flow path cross-sectional area than the upstream gas flow path, a drift of the gas flow is more likely to occur in the downstream gas flow path.

  Therefore, the upstream gas flow path is connected to the downstream side of the upstream gas flow path in a direction in which the downstream gas flow path having a larger cross-sectional area than the upstream gas flow path is bent. In the past, there has been proposed an apparatus for preventing the drift of the gas flow flowing into the downstream gas flow channel from within the downstream gas flow channel.

  This is, for example, an exhaust gas inlet serving as an upstream gas flow channel, and a downstream gas flow channel having a flow channel cross-sectional area larger than that of the exhaust gas inlet and being bent by approximately 90 degrees with respect to the exhaust gas inlet. A flow straightening plate (collision plate) perpendicular to the gas flow direction of the exhaust gas flowing in from the exhaust gas inlet is disposed in an exhaust gas duct having an exhaust gas outlet, and an inner corner portion that is closest to the exhaust gas outlet of the flow path bend Further, a plurality of the outer corner portions are arranged obliquely between the outermost corner portion which is the farthest from the exhaust gas outlet (see, for example, Patent Document 2).

  In addition, in order to provide a guide vane that is curved along the shape of the curved portion in the tube curved portion where the flow path is curved by about 90 degrees, and to prevent separation of the flow from the guide vane, the guide vane It has been conventionally proposed to provide an opening penetrating in the plate thickness direction (see, for example, Patent Document 3).

Japanese Patent No. 3775489 JP-A-8-327047 JP 2008-286396 A

  However, in the bag filter, when a drift occurs in the gas flow of the combustion exhaust gas flowing into the container through the gas inlet from the upstream inlet duct, one of the filter cloths provided in the container is one of the filter cloths provided in the container. Since local wear occurs in the filter cloth of the part and early damage occurs, the frequency of maintenance of each filter cloth increases.

  Therefore, in the bag filter, it is desired that the combustion exhaust gas flowing into the container through the gas inlet from the inlet duct serving as the upstream gas flow path does not cause a drift in the container.

  In the exhaust gas duct shown in Patent Document 2 which responds to the demand for preventing the drift of the gas flow, a rectifying plate perpendicular to the gas flow direction from the exhaust gas inlet is formed on the extension of the exhaust gas inlet, and the flow path is bent. Are arranged in an oblique manner between the inner corner portion and the outer corner portion of the portion, but with each of the rectifying plates, the direction of gas flow can be changed to a direction along each of the rectifying plates. It is like that.

  Therefore, in the exhaust gas duct, in order to generate an average gas flow in the entire cross section of the flow path at the exhaust gas outlet, a rectifying plate is provided over the entire area from the inner corner portion to the outer corner portion of the flow path bending portion. It is necessary to arrange and install.

  Therefore, if the configuration of the rectifying plate of the exhaust gas duct is applied to prevent the drift in the flow passage having a large flow passage cross-sectional area like the bag filter container described above, the required rectifying plate is required. However, the installation range of the rectifying plate is increased, which increases the number of man-hours and costs required to install the rectifying plate.

  In addition, although what was shown by the said patent document 3 is equipped with the structure which provided the opening in the guide vane, this guide vane is provided in a pipe curved part, Comprising: It is directly in the bending part of a gas flow path. It is not applicable. Furthermore, the opening of the guide vane is for preventing separation of the flow from the guide vane, and has a flow passage cross-sectional area larger than the upstream gas flow passage from the upstream gas flow passage. Moreover, there is no idea to prevent the drift of the gas flow flowing into the downstream gas flow path extending in the direction bent with respect to the gas flow direction of the upstream gas flow path.

  Accordingly, the present invention provides an upstream gas flow path and a downstream side having a flow path cross-sectional area larger than the upstream gas flow path and extending in a direction bent with respect to the gas flow direction of the upstream gas flow path. A gas rectifier that is provided in a connection portion with a gas flow path and can generate an average gas flow in a cross section of the downstream gas flow path, and a bag filter including the gas rectifier It is something to try.

The present invention, in order to solve the above problems, the upper stream side gas flow path, relative to the direction of gas flow in and having a large flow path cross-sectional area than the upstream side gas passage the upstream side gas passage A plurality of rectifying plates for bending the flow of gas from the upstream gas flow path are connected to a downstream gas flow path extending in the bending direction, and an inner corner portion of the flow path bending portion by each gas flow path. Are arranged so as to be sequentially shifted from the upstream side to the downstream side in the gas flow direction from the upstream gas flow path as the distance from the inner corner portion increases. Among the arranged rectifying plates, the gas along the flow direction of the gas from the upstream gas flow path is applied to more than half of the rectifying plates excluding the single or plural rectifying plates located closer to the side away from the inner corner portion. With an opening to let through part of The gas rectifying device having a structure that.

In the above configuration, each rectifying plate that bends the gas flow from the upstream gas flow path is arranged so as to be orthogonal to the gas flow direction from the upstream gas flow path.

The said structure WHEREIN: Let the opening part with which a current plate is provided be the structure which made 20-50% of the area of this current plate.

The said structure WHEREIN: It is set as the structure which provided the opening area adjustment means for changing the area of this opening part in the baffle plate provided with the opening part.

In addition , an inlet duct is connected as an upstream gas flow path to a gas inlet of a container containing a filter cloth, and the container is used as a downstream gas flow path and has a larger flow path cross-sectional area than the inlet duct, A bag filter having a configuration in which the gas rectifier of any one of the above configurations is provided at the gas inlet of the container in the bag filter configured to bend and flow the gas from the inlet duct in the container. And

According to the present invention, the following excellent effects are exhibited.
(1) An upstream gas flow channel and a downstream gas flow channel having a flow channel cross-sectional area larger than that of the upstream gas flow channel and extending in a direction bent with respect to the gas flow direction in the upstream gas flow channel A plurality of rectifying plates that bend the gas flow from the upstream gas flow path at a connection point to the inner corner portion of the flow path bending portion by each gas flow path As the distance further increases, the gas flow direction from the upstream gas flow path is sequentially arranged so as to be shifted from the upstream side to the downstream side. An opening for allowing a part of the gas along the gas flow direction from the upstream gas flow path to pass through more than half of the rectifying plates excluding one or a plurality of rectifying plates located on the side away from the corner portion A gas rectifier having a configuration comprising: Therefore, when the gas is allowed to flow into the downstream gas passage having a larger cross-sectional area than the upstream gas passage, it is possible to prevent the occurrence of drift in the downstream gas passage. An average gas flow can be generated in the cross section of the downstream gas flow path.
(2) Further, since the rectifying plate does not need to be provided near the outer corner of the flow path bending portion, the number of rectifying plates can be reduced and the installation range of the rectifying plates can be reduced. Man-hours and costs required for installation can be reduced.
( 3 ) The inlet duct is connected to the gas inlet of the container containing the filter cloth as an upstream gas flow path, and the container is used as the downstream gas flow path and has a larger channel cross-sectional area than the inlet duct, The bag filter configured to be able to bend and flow the gas from the inlet duct in the container has a configuration in which the gas rectifier described in (1 ) is provided at the gas inlet of the container. Since it is a bag filter, in addition to the same effects as the above (1) and (2), it is possible to prevent local early wear damage from occurring on some filter cloths. Therefore, the frequency of filter cloth maintenance can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows an embodiment of a gas rectifier according to the present invention, in which (a) is a schematic cut side view showing a configuration in which all rectifying plates are provided with openings, and (b) is an inner corner portion of a flow path bending portion. It is a general | schematic cutting side view which shows the principal part at the time of making the baffle plate arrange | positioned in the location which leaves | separates most into a form without an opening part. 1 shows the gas rectifier of FIG. 1, (a) is a schematic perspective view showing a configuration in which all rectifying plates are provided with openings, and (b) is a place farthest away from an inner corner portion of a flow path bending portion. It is a schematic perspective view which shows the principal part at the time of making the baffle plate to arrange | position into the type without an opening part. It is a cutaway side view showing an outline of a bag filter to which the gas rectifier of FIG. 1 is applied. As another embodiment of the present invention, a rectifying plate of a type in which the area of the opening is made variable is shown, (a) is a diagram showing a state where the area of the opening is maximized, (b) is an opening. It is a figure which shows the state which narrowed down the area. It is a figure which shows the flow velocity distribution of the gas in the vertical cross section of the container of a bag filter as a result of verifying the rectification effect by the gas rectifier of this invention. As a result of verifying the rectification effect by the gas rectifier of the present invention, it is a diagram showing the upward flow velocity distribution of gas in the horizontal section at the lower end position of the filter cloth of the bag filter container. It is a schematic perspective view of the gas rectification means used as a comparative example when verifying the rectification effect by the gas rectifier of the present invention. It is a figure which shows the flow velocity distribution of the gas in the vertical cross section of the container of a bag filter at the time of using the gas rectification | straightening means of FIG. It is a figure which shows the vertical flow rate distribution of the gas in the horizontal cross section in the filter cloth lower end position of the bag of the bag filter at the time of using the gas rectifier of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIGS. 1A, 1B and 3 show a case where the present invention is applied to a bag filter 1 as an embodiment of the gas rectifier of the present invention.

  Here, first, the configuration of the bag filter 1 shown in FIG. 3 will be outlined.

  The bag filter 1 includes a cylindrical container 2 having a rectangular cross section and extending in the vertical direction. The container 2 is provided with a gas outlet 3 at the side of the upper end, and further has a hopper shape at the bottom, and a gas inlet 4 at the side of the lower end of the container 2.

  The gas inlet 4 is connected to an inlet duct 5 for guiding a combustion exhaust gas 6 as a gas from a combustion furnace side (not shown).

  The container 2 is configured such that the flow passage cross-sectional area at the height position of the gas inlet 4 is larger than the flow passage cross-sectional area of the inlet duct 5. Further, the cross-sectional shape of the flow path at the height position of the gas inlet 4 in the container 2 is the gas flow direction of the combustion exhaust gas 6 flowing in the direction along the longitudinal direction of the inlet duct 5 from the inlet duct 5 (hereinafter, The dimension of the inflowing gas flow direction x) is set to be larger than the vertical dimension of the cross-sectional shape of the inlet duct 5 perpendicular to the inflowing gas flow direction x.

  As a result, the inlet duct 5 becomes an upstream gas flow path, the container 2 has a flow path cross-sectional area larger than the flow path cross-sectional area of the inlet duct 5, and with respect to the inflow gas flow direction x. The downstream gas flow path extends in the direction bent 90 degrees.

  A cell plate 7 in which a plurality of filter cloth mounting holes 8 are opened in a row in the vertical and horizontal directions is airtightly mounted at a position below the gas outlet 3 in the upper part of the container 2. Each filter cloth attachment hole 8 of the cell plate 7 supports the upper end of a retainer (not shown) which holds a cylindrical long and narrow bag-like filter cloth 9 from the lower side to the outer peripheral side. The filter cloths 9 are suspended below the cell plate integrally with the retainers, and the upper end openings of the filter cloths 9 communicate with the corresponding filter cloth attachment holes 8 respectively. is there.

  The gas rectifier 10 of the present invention applied to the bag filter 1 having the above-described configuration includes the downstream end of the inlet duct 5 and the container 2 as shown in FIGS. As a posture for bending the flow of the combustion exhaust gas 6 flowing into the vessel 2 from the inlet duct 5 through the gas inlet 4 to the connection point with the gas inlet 4 which is the upstream end portion in FIG. A plurality of strip-shaped rectifying plates 11 extending in a horizontal direction within a vertical plane orthogonal to the direction x are connected to an inner corner portion 12 (hereinafter simply referred to as an inner corner portion 12) of the flow path bending portion formed by the inlet duct 5 and the container 2. Are arranged in an oblique direction so as to be sequentially shifted from the upstream side to the downstream side in the inflowing gas flow direction x as the distance from the inner corner portion 12 increases.

  Further, each rectifying plate 11 includes an opening 13 for allowing a part of the gas flow in the direction along the inflow gas flow direction x of the combustion exhaust gas 6 flowing from the inlet duct 5 to pass therethrough. To do.

  More specifically, each of the rectifying plates 11 is divided into a plurality of, for example, five divided sections in the vertical direction perpendicular to the inflowing gas flow direction. An individual rectifying plate 11 is arranged for each position projected toward x. Accordingly, the rectifying plates 11 arranged in the oblique direction from the inner corner portion 12 are rectifying plates 11 adjacent to each other in the oblique direction so that adjacent end portions do not overlap with each other in the vertical direction. Is arranged. From the viewpoint of reducing the flow resistance of the combustion exhaust gas 6 flowing into the container 2 from the inlet duct 5, the inflowing gas flow for the rectifying plates 11 arranged in an oblique direction from the inner corner portion 12. The ratio between the interval in the direction x and the vertical height dimension of each rectifying plate 11 is preferably set to about 1: 1.

  The rectifying plates 11 arranged (arranged) at the predetermined locations are connected to each other via a support member 14 arranged in a vertical plane along the inflowing gas flow direction x, and the support member 14 And attached to the inner wall of the container 2. As a result, each of the rectifying plates 11 is supported from the inner wall of the container 2 via each support member 14.

  Each of the rectifying plates 11 has a configuration in which the opening 13 penetrates in the thickness direction at the center in the plane.

  The area of the opening 13 of each rectifying plate 11 is set in a range of 20 to 50% of the area of each rectifying plate 11. The reason why the lower limit of the range is set to 20% is that, when the area of the opening 13 is less than 20% of the area of each rectifying plate 11, it has been found from the test results described later that the rectifying effect is insufficient. It is. On the other hand, the reason why the upper limit of the range is set to 50% is that when the area of the opening 13 exceeds 50% of the area of each rectifying plate 11, the strength is lowered (it is difficult to ensure the strength).

  Thereby, in the gas rectifier 10 of the present invention, as shown in FIG. 1A, when the combustion exhaust gas 6 flows into the container 2 as the gas flow in the inflow gas flow direction x from the inlet duct 5, The gas flow in the portion of the combustion exhaust gas 6 that collides with the surface of each rectifying plate 11 is directed downstream of the container 2 along the surface of each rectifying plate 11 as indicated by an arrow y in FIG. The direction of the gas flow is changed in the upward direction, that is, in the vertical direction. On the other hand, in each of the rectifying plates 11, a part of the gas flow that flows into the opening 13 out of the gas flow along the inflow gas flow direction x of the combustion exhaust gas 6 is retained in the inflow gas flow direction x. It passes through the opening 13.

  Therefore, in each region between the two rectifying plates 11 adjacent to each other among the rectifying plates 11 arranged in the oblique direction from the inner corner portion 12, the side farther from the inner corner portion 12. The flow direction of the inflowing gas that has passed through the opening 13 of the rectifying plate 11 located on the side close to the inner corner portion 12 and the gas flow (arrow y) vertically directed by the surface of the rectifying plate 11 located at As x gas flows occur, these two gas flows in different directions will interfere with each other. Therefore, in each of the above regions, a gas flow (arrow z) spreading obliquely upward that intersects with the arrangement direction of the respective rectifying plates 11 is generated by the interference of the gas flows in the two directions.

  As described above, in the gas rectifying device 10 of the present invention, each rectifying plate 11 having the opening 13 can generate a gas flow that spreads obliquely upward. It is not necessary to provide the current plate 11 near the outer corner of the bent portion. Therefore, in the gas rectifying device 10 of the present invention, as shown in FIG. 3, the rectifying plate 11 disposed at a position farthest away from the inner corner portion 12 has an inflow gas flow in the container 2 as a downstream gas flow path. It may be arranged near the middle of the width dimension in the direction x.

  As shown in FIGS. 1 (a) and 2 (a), among the rectifying plates 11, the rectifying plate 11 disposed at a position farthest from the inner corner portion 12 has the opening 13. In the case where it is provided, the gas flow in the vertical direction formed by the surface of the other rectifying plate 11 does not interfere with the gas flow in the inflow gas flow direction x passing through the opening 13. For this reason, the gas flow in the inflow gas flow direction x that has passed through the opening 13 of the rectifying plate 11 directly hits the side wall (see FIG. 3) facing the side wall provided with the gas inlet 4 in the container 2. At that time, the gas flow direction can be changed upward, which is the downstream side of the container 2.

  At this time, the side wall (see FIG. 3) of the container 2 facing the side wall provided with the gas inlet 4 is included in the combustion exhaust gas 6 as the gas flow of the combustion exhaust gas 6 directly hits it. When there is a concern about abrasion due to dust, as shown in FIG. 1B and FIG. 2B, a current plate arranged at a position farthest from the inner corner portion 12 is not provided with an opening portion 13. The rectifying plate 11a may be used.

  When the bag filter 1 equipped with the gas rectifier 10 of the present invention having the above-described configuration is used, the combustion exhaust gas 6 guided through the inlet duct 5 is caused to flow into the container 2 from the gas inlet 4. As a result, the gas flow in the inflow gas flow direction x of the combustion exhaust gas 6 flowing into the container 2 reaches the rectifying plates 11 and 11a in the gas rectifying device 10 of the present invention.

  The gas flow of the combustion exhaust gas 6 reaching each of the rectifying plates 11 hits the surface of each of the rectifying plates 11 and 11a and passes through the opening 13 of each rectifying plate 11 and the gas flow (arrow y) directed upward in the vertical direction. Due to the interference between the gas flow in the inflow gas flow direction x and the two gas flows, a gas flow spreading obliquely upward is generated. Therefore, a gas flow dispersed in the cross section of the flow path is generated in the container 2.

  Further, in the container 2, as the direction of the gas flow of the combustion exhaust gas 6 becomes obliquely upward, the upward flow velocity of the gas flow is reduced. Thereby, the gas flow comes to have an averaged flow velocity distribution in the cross section of the flow path of the container 2.

  Therefore, in the container 2, occurrence of drift of the combustion exhaust gas 6 is prevented.

  Thus, according to the gas rectifier 10 of the present invention, in the bag filter 1, the container 2 as the downstream gas flow path having a larger flow cross-sectional area than the inlet duct 5 as the upstream gas flow path. When the combustion exhaust gas 6 is caused to flow into the container 2, it is possible to prevent the occurrence of drift in the container 2 and to generate an average gas flow in the cross section of the flow path of the container 2.

  For this reason, in the said bag filter 1, it can prevent that the local early wear damage arises in some filter cloth 9 among each filter cloth 9. FIG. Therefore, the maintenance frequency of each filter cloth 9 can be reduced.

  Further, the gas rectifier 10 of the present invention does not need to be provided with the rectifying plate 11 near the outer corner of the flow passage bent portion by the inlet duct 5 and the container 2 and is disposed at a position farthest from the inner corner portion 12. Since the rectifying plate 11 to be operated can be disposed near the middle of the width dimension in the inflow gas flow direction x in the container 2 as the downstream gas flow path, the conventional gas rectifying means as shown in Patent Document 2 is used. Compared to the case where the number of rectifying plates 11 is adopted, the number of the rectifying plates 11 can be reduced and the installation range of the rectifying plates 11 can be reduced, so that the man-hours and costs required for installing the respective rectifying plates 11 can be reduced. Can do.

  Furthermore, the gas rectifying device 10 of the present invention can arrange the rectifying plates 11 and 11a in a vertical plane even in the case where an obliquely upward gas flow of the combustion exhaust gas 6 is generated in the container 2. Therefore, it is possible to prevent the dust contained in the combustion exhaust gas such as fly ash from accumulating on each rectifying plate 11.

  Next, FIGS. 4A and 4B show another embodiment of the present invention, which includes an opening 13 of the gas rectifier 10 shown in FIGS. 1A and 1B to FIG. Each rectifying plate 11 is provided with an opening area adjusting means for making the area of the opening 13 variable.

  More specifically, each of the rectifying plates 11 is provided with a rectangular opening 13 having an area of 50% of the area of the rectifying plate 11 at the center in the plane.

  The opening area adjusting means of the opening 13 is provided with a pair of guide rails 15 extending in parallel to the long sides outside the pair of long sides of the opening 13 on the surface (one side) of the rectifying plate 11, Two door bodies 16 are slidably attached between the pair of guide rails 15. As shown in FIG. 4 (b), each door body 16 is in a state where the door bodies 16 cover the ends of the opening 13 in the longitudinal direction as much as possible. The opening area of the opening 13 remaining between the current plate and the current plate 11 can be reduced to 20% of the area of the current plate 11.

  Other configurations are the same as those shown in FIGS.

  According to the gas rectifier 10 of the present embodiment, the same effects as in the above embodiment can be obtained.

  Furthermore, the area of the opening 13 of each rectifying plate 11 is 50% of the area of the rectifying plate 11 in a state where each door 16 is retracted to a position not overlapping the opening 13 as shown in FIG. 4 (b), it can be freely adjusted within a range of up to 20% of the area of the rectifying plate 11 in a state where the opening 13 is covered to the maximum by each door body 16, as shown in FIG. .

  Therefore, the connecting portion between the inlet duct 5 and the container 2 according to the conditions such as the size and size ratio of the cross-sectional area of the inlet duct 5 and the container 2 of the bag filter 1 to be applied and the flow velocity of the combustion exhaust gas 6. Even if the area desired for the opening 13 of the rectifying plate 11 in the gas rectifying device 10 of the present invention installed in the gas rectifier is variously different in the range of 20 to 50% of the area of the rectifying plate 11, the opening The area of the opening 13 can be optimally adjusted by opening and closing the door body 16 mounted on the door 13.

  Therefore, it is possible to eliminate the necessity of separately preparing the rectifying plates 11 having different areas of the opening 13, and it is possible to obtain a configuration advantageous for generalization of the gas rectifying device 10 of the present invention.

  In addition, this invention is not limited only to the said embodiment, The number of several baffle plates 11 arranged in the diagonal direction from the inner corner part 12 is the flow-path cross-sectional area of the inlet duct 5, and the container 2 You may increase / decrease suitably according to the magnitude | size of a flow-path cross-sectional area.

  The rectifying plate 11 is provided in a posture other than the posture orthogonal to the inflowing gas flow direction x as long as the flow of the combustion exhaust gas 6 flowing into the container 2 from the inlet duct 5 serving as the upstream gas flow path is bent. It may be.

  The rectifying plate 11 may include a plurality of openings as long as the area of the opening 13 is in the range of 20 to 50% of the area of the rectifying plate 11.

  The vertical and horizontal dimensions of the current plate 11 may be changed as appropriate.

  The support member 14 that supports the plurality of rectifying plates 11 that are arranged obliquely from the inner corner portion 12 is an actual connection portion between the upstream gas flow path and the downstream gas flow path such as the inlet duct 5 and the container 2. You may change suitably according to a shape.

  In FIG. 1B and FIG. 2B, the case where only the current plate arranged at the position farthest from the inner corner portion 12 is the current plate 11a having no opening 13 is shown. Of the rectifying plates 11 arranged obliquely from the corner portion 12, less than half of the rectifying plates that are arranged closer to the side away from the inner corner portion 12 may be used as the rectifying plate 11 a having no opening 13. Good. Also in this case, more than half of the rectifying plates 11 disposed at positions close to the inner corner portion 12 include the opening portion 13, and the gas flow of the combustion exhaust gas 6 passing through the opening portion 13 is generated. The rectifying plate 11a without the opening 13 interferes with the gas flow directed upward in the vertical direction, and a gas flow spreading obliquely upward can be generated. Furthermore, in this case, it is possible to more reliably prevent the gas flow of the combustion exhaust gas 6 from directly hitting the side wall (see FIG. 3) facing the side wall provided with the gas inlet 4 in the container 2.

  The gas rectifier 10 of the present invention has a channel cross-sectional area larger than the channel cross-sectional area of the upstream gas flow channel on the downstream side of the upstream gas flow channel and in the gas flow direction in the upstream gas flow channel. As long as the downstream gas flow path extending in the direction of bending is connected, the present invention may be applied to any gas flow path other than the connection portion between the inlet duct 5 and the container 2 in the bag filter 1.

  Of course, various modifications can be made without departing from the scope of the present invention.

(1)
With respect to the bag filter 1 equipped with the gas rectifier 10 of the present invention shown in FIGS. 1 (a), 1 (b) to 3, the flow velocity in the container 2 when the gas flows into the container 2 from the inlet duct 5. The distribution was analyzed. The gas rectifying device 10 of the present invention includes a rectifying plate 11a having no opening 13 at a position farthest away from the inner corner portion 12, as shown in FIGS. 1 (b) and 2 (b). Format. The area of the opening 13 (see FIGS. 1A, 1B, 2A, and 2B) of the rectifying plate 11 other than that was set to 30% of the area of the rectifying plate 11.

As analysis conditions, air was used as a gas. The pressure was atmospheric pressure. The gas flow rate was 2100 Nm ³ / hr as a circulating flow for the bag filter 1. The gas temperature was 220 degrees. The filter cloth (see FIG. 3) was a porous layer equivalent in pressure loss (120 mmAq).

  FIG. 5 is a view showing a flow velocity distribution in a vertical section passing through the center of the gas rectifier of the present invention. In addition, the numerical value attached | subjected to the line in a figure has shown the flow velocity (m / s) (FIG.6, FIG.8, FIG.9 mentioned later is also the same).

  FIG. 6 is a diagram showing the upward flow velocity distribution of the gas in the horizontal section at the lower end position of the filter cloth 9 (see FIG. 3) in the container 2 of the bag filter 1. Note that the position of the inlet duct 5 is indicated by a one-dot chain line (the same applies to FIG. 9 described later).

(2)
As a comparative example, the bag filter 1 equipped with the gas rectifying means 17 configured as shown in FIG. 7 was analyzed for the flow velocity distribution in the container 2 when the gas flows into the container 2 from the inlet duct 5.

  As in the gas rectifying device 10 of the present invention, the gas rectifying means 17 shown in FIG. 7 is provided with a plurality of rectifying plates 18 arranged in a vertical plane arranged in an oblique direction from the inner corner portion 12 (FIG. 8). Each of the rectifying plates 18 is provided with an opening 19 that is less than 20% (about 18%) of the area of the rectifying plate.

  FIG. 8 is a view showing a flow velocity distribution in a vertical section passing through the center of the gas rectifying means 17 in FIG.

  FIG. 9 is a view showing the upward flow velocity distribution of the gas in the horizontal section at the lower end position of the filter cloth 9 (see FIG. 3) in the container 2 of the bag filter 1 provided with the gas rectifying means 17 of FIG. is there.

  From the analysis results of FIG. 5, FIG. 6, FIG. 8, and FIG. 9, the following conclusions were obtained.

  That is, from the analysis result of FIG. 5, it was found that according to the gas rectifier 10 of the present invention, it is possible to generate a gas flow that spreads obliquely upward by the respective rectifying plates 11 and 11a.

  On the other hand, from the analysis result of FIG. 8, when the area of the opening 19 provided in the rectifying plate 18 is less than 20% as in the gas rectifying means 17 shown in FIG. 7, the gas flow hitting each rectifying plate 18 is Most of the gas flow is directed upward in the vertical direction along the surface of each rectifying plate 18, so that the flow velocity distribution above the installation location of the rectifying plate 18 is increased in the container 2 of the bag filter 1. Was found to occur.

  Further, from the analysis result of FIG. 6, according to the gas rectifier 10 of the present invention, in the horizontal section at the lower end position of the filter cloth 9 in the container 2 of the bag filter 1 (see FIG. 3) It has been found that a gas flow with less uneven flow velocity can be generated throughout.

  On the other hand, from the analysis result of FIG. 9, in the gas rectifying means 17 shown in FIG. 7, the flow velocity distribution in the horizontal section at the lower end position of the filter cloth 9 in the container 2 of the bag filter 1 (see FIG. 3) is obtained. It was found that a large bias occurred.

1 Bag filter 2 Container (downstream gas flow path)
4 Gas inlet 5 Inlet duct (upstream gas flow path)
6 Combustion exhaust gas (gas)
9 Filter cloth 10 Gas rectifier 11, 11a Rectifying plate 12 Inner corner 13 Opening 15 Guide rail (opening area adjusting means)
16 Door (opening area adjustment means)

Claims (5)

Connection between the upstream gas flow path and a downstream gas flow path having a larger flow path cross-sectional area than the upstream gas flow path and extending in a direction bent with respect to the gas flow direction in the upstream gas flow path The plurality of rectifying plates that bend the gas flow from the upstream gas flow passage are separated from the inner corner portion from positions close to the inner corner portion of the flow passage bending portion by each gas flow passage. According to the above, and arranged in order to be shifted from the upstream side to the downstream side in the gas flow direction from the upstream gas flow path,
Furthermore, the flow direction of the gas from the upstream gas flow path is more than half of the rectifying plates arranged above the rectifying plate excluding the single or plural rectifying plates located closer to the side away from the inner corner portion. A gas rectifier having a configuration including an opening for allowing a part of the gas to pass therethrough. Each rectifier plate to bend the flow of gas from the upstream side gas passage, according to claim 1 Symbol placement of the gas rectifying and arranged to be orthogonal orientation relative to the direction of flow of the gas from the upstream side gas passage apparatus. The gas rectifier according to claim 1 or 2 , wherein an opening provided in the rectifying plate is 20 to 50% of an area of the rectifying plate. The gas rectifier according to any one of claims 1 to 3, wherein an opening area adjusting means for changing an area of the opening is provided on the current plate having the opening. An inlet duct is connected to a gas inlet of a container containing a filter cloth as an upstream gas flow path, and the container is used as a downstream gas flow path and has a flow passage cross-sectional area larger than that of the inlet duct. In the bag filter which is made to be able to bend and flow the gas from above in the container,
A bag filter comprising a gas rectifier according to any one of claims 1 to 4 at a gas inlet of the container.

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