JP2014126330A - Exhaust heat boiler, heat exchanger, dust removal device provided in heat exchanger, and heat exchanger manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchanger capable of efficiently removing dust.SOLUTION: A heat exchanger 20 heating a heat medium using heat of gas flowing in a casing 11 and containing dust, includes: a heat transfer tube 22 through which the heat medium passes; a coupling shaft 51 coupled to a plurality of parts of the heat transfer tube 22; and a dust removal device 50 removing the dust adhering to the heat transfer tube 22. The heat transfer tube 22 includes straight tubular parts 23 and folded parts 24 and 25 alternately arranged so that the heat transfer tube 22 can extend in a meandering fashion in plane. The dust removal device 50 includes striking means 55 for applying a striking force to the coupling shaft 51.

Description

  The present invention relates to a heat exchanger that heats a heat medium in a heat transfer tube using the heat of a gas containing dust that flows inside a casing, and to an exhaust heat boiler that includes the heat exchanger. Moreover, this invention relates to the dust removal apparatus which removes the dust adhering to the heat exchanger tube of a heat exchanger. The present invention also relates to a method for manufacturing a heat exchanger.

  In facilities where high-temperature exhaust gas is generated, such as cement firing plants, steelworks, metal smelters, chemical factories, garbage incinerators, and geothermal power plants, exhaust heat boilers are provided to recover the heat of the exhaust gas. An exhaust heat boiler collects the heat of exhaust gas, for example using the heat exchanger which heats the heat carrier in a heat exchanger tube using the heat of exhaust gas.

  The exhaust gas contains dust, and the dust gradually adheres and accumulates on the surface of the heat transfer tube during the operation of the exhaust heat boiler. Since dust inhibits heat conduction between the exhaust gas and the heat transfer medium in the heat transfer tube, if the dust is left attached to the heat transfer tube, the efficiency of the exhaust heat boiler is reduced. In order to solve such a problem, it is known to provide a heat exchanger with a dust removing device for removing dust adhering to the surface of the heat transfer tube. For example, Patent Document 1 proposes a dust removing device that includes a striking unit that applies striking force to a connecting shaft that is coupled to the lower end of a heat transfer tube. According to such a dust removing device, the heat transfer tube can be vibrated using the striking force, whereby the dust attached to the surface of the heat transfer tube can be shaken off.

JP 59-28813 A

  The heat exchanger includes a plurality of heat transfer tubes. Each heat transfer tube normally extends in a meandering manner by alternately connecting straight tube portions and folded portions, and thus each heat transfer tube has a planar panel shape. Moreover, each heat exchanger tube is arranged along the direction orthogonal to a panel-shaped plane. Moreover, in the conventional dust removal apparatus, the connecting shaft extends in the arrangement direction so as to be connected to each of the plurality of heat transfer tubes arranged in the arrangement direction. In this case, it is considered that the striking force applied to the connecting shaft acts to displace the plurality of heat transfer tubes integrally along the arrangement direction, rather than to vibrate the surface of the heat transfer tubes. Therefore, in the conventional dust removing device, it is considered that the striking force applied to the connecting shaft is not effectively used for the purpose of vibrating the surface of the heat transfer tube to remove dust.

  An object of this invention is to provide the dust removal apparatus which can solve such a subject effectively. Moreover, an object of this invention is to provide the manufacturing method of the heat exchanger provided with the dust removal apparatus, the waste heat boiler provided with the heat exchanger, and a heat exchanger.

  A first aspect of the present invention is a heat exchanger that heats a heat medium using heat of a gas containing dust flowing inside the casing, and is disposed inside the casing, and the heat medium is passed through the heat exchanger. A heat transfer tube, a connecting shaft connected to a plurality of portions of the heat transfer tube, and a dust removing device for removing dust adhering to the heat transfer tube, the heat transfer tube having a straight tube portion and a folded portion. And the straight pipe part and the folded part are alternately arranged so that the heat transfer pipes meander in a plane, and the dust removing device applies a striking force to the connecting shaft. A heat exchanger having means.

  In the heat exchanger according to the present invention, the connecting shaft may be connected to an outermost portion of the folded portion of the heat transfer tube.

  In the heat exchanger according to the present invention, a plane on which the heat transfer tubes are arranged in a meandering manner is parallel to a gas flow direction, and the straight pipe portion of the heat transfer tubes is arranged to extend in a vertical direction. May be.

  In the heat exchanger according to the present invention, the connecting shaft and the striking means may be disposed inside the casing.

  In the heat exchanger according to the present invention, the heat exchanger is a horizontal heat exchanger in which gas flows in a horizontal direction, and the casing is supported from the side by a plurality of support columns extending in a vertical direction, At least some of the columns may be arranged so as to overlap the heat transfer tubes when viewed from the side.

  In the heat exchanger according to the present invention, a plurality of heat transfer tubes, including the heat transfer tubes, are arranged along an arrangement direction orthogonal to a plane in which the heat transfer tubes are formed in a serpentine shape, and are adjacent in the arrangement direction. A pair of the heat transfer tubes may be provided with an interval holding mechanism for maintaining an interval between the adjacent heat transfer tubes to be equal to or greater than a predetermined arrangement interval.

  In the heat exchanger according to the present invention, the interval holding mechanism includes a first spacer attached to one of the pair of adjacent heat transfer tubes in the arrangement direction and a first spacer attached to the other of the pair of adjacent heat transfer tubes. And the first spacer and the second spacer may be configured to contact each other when the distance between the pair of the heat transfer tubes in the arrangement direction is the arrangement interval. .

  In the heat exchanger according to the present invention, the longitudinal direction of the end of the first spacer that contacts the second spacer, and the end of the second spacer that contacts the first spacer. The longitudinal direction may be non-parallel.

  In the heat exchanger according to the present invention, the heat exchanger is a horizontal heat exchanger in which gas flows in a horizontal direction, and the folded portion of the heat transfer tube is connected to upper ends of two adjacent straight tube portions. An upper folded portion, and a lower folded portion connected to the lower ends of the two adjacent straight pipe portions, the heat transfer tube extending along the extending direction of the heat transfer tube, A support mechanism for supporting the heat transfer tube is attached, and the support mechanism is coupled to the main body portion extending through the vicinity of the plurality of upper folding portions of the heat transfer tube, and the upper folding portion. A lower support portion that supports the upper folded portion from above, and an upper support portion that contacts the upper folded portion from above, wherein one upper support portion contacts the plurality of upper folded portions. Even though it is configured to There.

  In the heat exchanger according to the present invention, a plurality of notches each adapted to a contour of the upper folded portion may be formed at the lower end of the upper support portion of the support mechanism.

  In the heat exchanger according to the present invention, a plurality of heat transfer tubes, including the heat transfer tubes, are arranged along an arrangement direction perpendicular to a plane in which the heat transfer tubes are formed in a meandering shape, and the main body of the support mechanism The portion passes through the vicinity of the plurality of upper folded portions of the one heat transfer tube located on one side of the main body portion and the plurality of the heat transfer tubes located on the other side of the main body portion. The lower support part extends through the vicinity of the upper folded part, the lower support part is coupled to the main body part, and one lower support part that supports the upper folded part of the one heat transfer tube from below, A lower support portion coupled to the main body portion and supporting the upper folded portion of the other heat transfer tube from below, wherein the upper support portion is coupled to the main body portion and the one heat transfer tube. From above to the upper folded part One upper support part that touches and the other upper support part that is coupled to the main body part and contacts the upper folded part of the other heat transfer tube from above, and the one upper support part is 1 The upper support portion of the book is configured to come into contact with the plurality of upper folded portions of the one heat transfer tube, and the other upper support portion is configured such that one upper support portion is a plurality of the other heat transfer tubes. It may be configured to contact the upper folded portion.

  A second aspect of the present invention is a dust removing device that is provided in the heat exchanger described above and removes dust adhering to the heat transfer tube, wherein the striking means applies a striking force to the connecting shaft of the heat exchanger. A dust removing device having

  A third aspect of the present invention is an exhaust heat boiler for recovering heat from exhaust gas containing dust, wherein the heat medium is disposed using a casing and heat of the exhaust gas that is disposed inside the casing and flows inside the casing. A heat exchanger for heating, and the heat exchanger is an exhaust heat boiler including the heat exchanger described above.

  4th this invention is a manufacturing method of the said heat exchanger, Comprising: The heat exchanger tube unit formation process which connects the said connection axis | shaft to the said heat exchanger tube outside the said casing, and forms a heat exchanger tube unit, An arrangement step of arranging a heat transfer tube unit inside the casing.

  In the heat exchanger manufacturing method according to the present invention, in the heat exchanger, a plurality of heat transfer tubes are arranged along the arrangement direction perpendicular to the plane in which the heat transfer tubes are formed in a meandering shape, including the heat transfer tubes. The heat transfer tube unit forming step includes a step of combining a plurality of the heat transfer tube units to form a heat transfer tube module, and the arranging step includes arranging the heat transfer tube unit in the form of the heat transfer tube module in the casing. The process of arrange | positioning inside may be included.

  According to the present invention, the heat exchanger includes a connecting shaft connected to a plurality of portions of the heat transfer tube, and a dust removing device that removes dust attached to the heat transfer tube. The heat transfer tube has a straight tube portion and a folded portion that are alternately arranged. For this reason, the heat transfer tube is formed in a meandering manner in a plane. The dust removing device also has a striking means for applying a striking force to the connecting shaft. For this reason, the dust removing device can apply a striking force to the heat transfer tube in a direction in which the rigidity of the heat transfer tube is high. Therefore, the striking force applied to the heat transfer tube is efficiently converted into the vibration of the heat transfer tube. Thereby, the dust adhering to the heat transfer tube can be efficiently removed.

FIG. 1 is a side view showing an exhaust heat boiler including a plurality of heat exchangers according to an embodiment of the present invention. FIG. 2 is a plan view showing the exhaust heat boiler of FIG. FIG. 3 is a side view showing a heat transfer tube of a heat exchanger and a dust removing device attached to the heat transfer tube. FIG. 4 is a plan view showing the dust removing device of FIG. 3. FIG. 5 is a perspective view showing a connecting shaft of the dust removing device. 6 is a cross-sectional view showing a support mechanism for supporting a heat transfer tube in the vertical direction as viewed from the VI-VI direction in FIG. 3. FIG. 7 is a cross-sectional view showing a distance holding mechanism provided between a pair of heat transfer tubes. FIG. 8 is a perspective view showing the interval holding mechanism of FIG. FIG. 9A is a plan view showing one process for forming a heat transfer tube panel. FIG. 9B is a plan view showing one process for forming the heat transfer tube panel. FIG. 9C is a side view showing a step of arranging the heat transfer tube panel inside the casing. FIG. 10A is a plan view showing one process for forming a panel unit. FIG. 10B is a side view showing a step of arranging the panel unit inside the casing. FIG. 11 is a diagram illustrating a state in which a striking force is applied to the heat transfer tube according to the embodiment of the present invention. FIG. 12 is a side view showing a connecting shaft of a dust removing device according to a comparative embodiment. FIG. 13 is a plan view showing a dust removing device according to a comparative embodiment. FIG. 14A is a diagram illustrating a state in which a striking force is applied to a heat transfer tube according to a comparative embodiment. FIG. 14B is a diagram illustrating a state in which the striking force is applied to the heat transfer tube according to the comparative embodiment. FIG. 15 is a plan view showing a modification of the support column that supports the casing. FIG. 16 is a perspective view showing a modified example of the connecting shaft of the dust removing device. FIG. 17 is a plan view showing a modification of the hitting means of the dust removing device. FIG. 18 is a side view showing a modification of the support mechanism. FIG. 19 is a longitudinal sectional view showing the support mechanism of FIG. 18 as viewed from the XVIII-XVIII direction. FIG. 20A is a side view showing a step for forming the support mechanism of FIG. FIG. 20B is a side view showing one step for forming the support mechanism of FIG. 18. FIG. 21 is a longitudinal sectional view showing a modified example of the support mechanism. FIG. 22 is a plan view showing an example in which heat transfer tubes are arranged in a staggered manner. FIG. 23 is a perspective view showing a coupling mechanism that couples two adjacent heat transfer tubes shown in FIG. 22. FIG. 24 is a longitudinal sectional view showing a modification of the support mechanism. FIG. 25 is a perspective view showing a modified example of the connecting shaft of the dust removing device. FIGS. 26A, 26 </ b> B, and 26 </ b> C are diagrams illustrating the results of calculating the frequency of vibration generated when a striking force is applied to the heat transfer tube according to the embodiment using simulation. FIGS. 27A, 27B, and 27C are diagrams illustrating the results of calculating the frequency of vibration generated when a striking force is applied to the heat transfer tube according to the comparative example using simulation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS. In the drawings, elements that represent the same function may be denoted by the same reference numerals and description thereof may be omitted. First, the entire exhaust heat boiler 10 that recovers the heat of exhaust gas will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view showing an exhaust heat boiler 10 installed in a cement firing plant, and FIG. 2 is arranged inside the casing 11 with the upper surface of the casing 11 of the exhaust heat boiler 10 removed for convenience. It is a top view which shows typically the positional relationship of the several heat exchanger 20 which is. In addition, a side view means the figure at the time of observing from the direction orthogonal to the side surface 12 of the casing 11. FIG.

(Exhaust heat boiler)
The exhaust heat boiler 10 is introduced with high-temperature exhaust gas containing dust discharged from a suspension preheater of a cement firing plant. 1 and 2, an arrow with a symbol F represents the flow direction of exhaust gas introduced into the exhaust heat boiler 10. In the present embodiment, a horizontal exhaust heat boiler 10 and a heat exchanger 20 that recover heat from exhaust gas flowing in the horizontal direction will be described. However, the present invention is not limited to this, and the technical idea of the present invention may be applied to a vertical exhaust heat boiler and a heat exchanger that recover heat from exhaust gas flowing in the vertical direction.

  The exhaust heat boiler 10 includes a casing 11 and a plurality of heat exchangers 20 that are arranged along the flow direction of the exhaust gas and heat the heat medium using the heat of the exhaust gas flowing inside the casing 11. . The casing 11 is attached to the side surface 12 of the casing 11 and supported from the side by a plurality of support columns 13 extending in the vertical direction. Each heat exchanger 20 has a plurality of heat transfer tubes 22. Further, below each heat exchanger 20, a hopper 14 is provided for guiding the dust adhering to the heat exchanger 20 downward.

  Although the role of the plurality of heat exchangers 20 is not particularly limited, for example, the heat exchanger 20 disposed on the most upstream side of the exhaust gas flow functions as the superheater SH and is disposed on the downstream side of the superheater SH. The made heat exchanger 20 functions as an evaporator GEN, and the heat exchanger 20 arranged on the downstream side of the evaporator GEN functions as a economizer ECO. In this specification, unless otherwise specified, the upstream side or the downstream side is a term that expresses a positional relationship based on the direction of the flow of exhaust gas. In FIG. 1, a heat transfer tube 22 that is disposed inside the casing 11 and that constitutes the heat exchanger 20 is drawn with a dotted line. The heat transfer tube 22 allows a heat medium that exchanges heat with exhaust gas to pass through the tube. In order to perform efficient heat exchange, each heat transfer tube 22 extends in a meandering manner in a plane parallel to the flow direction of the exhaust gas, as shown in FIG. In FIG. 1, a connecting shaft 51 and a hitting means 55, which will be described later, are also indicated by dotted lines.

  As shown in FIG. 2, the plurality of heat transfer tubes 22 of the heat exchanger 20 are arranged in the arrangement direction A. The arrangement direction A is, for example, a direction orthogonal to the surface in which the heat transfer tubes 22 extend in a meandering manner. As described above, the heat transfer tube 22 extends in a meandering manner in a plane parallel to the flow direction F of the exhaust gas. Therefore, the overall shape of the heat transfer tube 22 can also be expressed as a panel shape. In FIG. 2, the heat transfer tube 22 is drawn in a panel shape. Hereinafter, a comprehensive shape formed by the heat transfer tubes extending in a serpentine shape is sometimes referred to as a “heat transfer tube panel”, and a plane formed by the heat transfer tube panels is sometimes referred to as a “heat transfer tube panel surface”.

(Heat exchanger)
Next, with reference to FIG. 3 thru | or FIG. 8, the heat exchanger 20 which concerns on this Embodiment is demonstrated in detail. FIG. 3 is a view showing one heat transfer tube 22 of the heat exchanger 20 and other components attached to the heat transfer tube 22. In the present embodiment, the heat transfer tube 22 extends in the vertical direction, and a plurality of straight tube portions 23 arranged along the gas flow direction F and a plurality of folded portions that connect two adjacent straight tube portions 23. And have. The folded portion is connected to the upper ends of two adjacent straight pipe portions 23, and is connected to the upper folded portion 24 having a U-shape and the lower ends of the two adjacent straight pipe portions 23, and has a U-shape. And a lower folded portion 25 made of The heat transfer tube panel surface described above is formed by alternately arranging the plurality of straight tube portions 23 and the plurality of folded portions 24 and 25 in the same plane. The heat medium flowing in from the upper right inlet portion in FIG. 3 flows in a meandering manner in the heat transfer tube 22 while being sequentially folded at the upper folded portion 24 and the lower folded portion 25 as indicated by an arrow f. The heat medium flowing in the heat transfer tube 22 exchanges heat with the exhaust gas mainly in the straight tube portion 23, and then flows out from the upper left outlet portion in FIG.

As shown in FIG. 3, the heat exchanger 20 further includes a dust removing device 50 that removes dust attached to the heat transfer tubes 22. The dust removing device 50 is configured to apply a striking force to the heat transfer tube 22 in a direction in which the heat transfer tube 22 extends in the surface of the heat transfer tube panel (hereinafter also referred to as “heat transfer tube extending direction”). For example, the heat exchanger 20 is provided with a connecting shaft 51 that extends in the heat transfer tube extending direction and is connected to a plurality of portions of at least one heat transfer tube 22, and the dust removing device 50 includes a heat transfer tube extension. A striking means 55 for applying a striking force to the connecting shaft 51 in the present direction is provided. FIG. 3 shows an example in which the connecting shaft 51 is connected to the outermost portion 25 a of the plurality of lower folded portions 25 of the heat transfer tube 22 via the contact plate 53 and the connecting portion 52. The outermost portion of the folded portion is a portion that becomes a boundary where the extending direction of the heat transfer tube 22 is reversed. In the lower folded portion 25, the outermost portion 25a is a portion in which the direction in which the heat transfer tube 22 extends is reversed from the lower direction to the upper direction, and is the lowest position. In the upper folded portion 24, the outermost portion 24a is a portion where the direction in which the heat transfer tube 22 extends is reversed from the upper direction to the lower direction and is the uppermost portion. Although the specific configuration of the hitting means 55 is not particularly limited, for example, the hitting means 55 includes a hammer 55 a that applies a hitting force to the connecting shaft 51. According to the present embodiment, the plurality of portions of the heat transfer tube 22 are connected by the connecting shaft 51 via the contact plate 53 and the connecting portion 52 in the lower folded portion 25. For this reason, when a striking force is applied to one end portion of the connecting shaft 51 by the striking means 55, the vibration is transmitted to the entire heat transfer tube panel, whereby the dust adhering to the surface of the heat transfer tube 22 can be dropped. . In particular, in the case of the embodiment of FIG. 3, since the straight pipe portion 23 of the heat transfer tube 22 is arranged vertically, the dust adhering to the surface of the straight pipe portion 23 is caused by vibration and gravity. It can be removed more easily.
In the present specification, the term “extending direction” means a direction in which an object spreads when viewed macroscopically. On the other hand, the term “extending direction” means a direction in which an object spreads when viewed microscopically. For example, when viewed microscopically, the heat transfer tube 22 extends in the vertical direction in the straight tube portion 23 and extends in the circumferential direction in the folded portions 24 and 25. On the other hand, when viewed macroscopically, it can be said that the heat transfer tube 22 extends parallel to the gas flow direction F.

  As shown in FIG. 3, the heat transfer tube 22 is supported and fixed in the horizontal direction and the vertical direction above the heat transfer tube 22 by using a support mechanism 30 extending along the heat transfer tube extending direction. In the following description, a unit in which one or a plurality of heat transfer tubes 22 connected to the connecting shaft 51 is combined so that they can be handled integrally is sometimes referred to as a heat transfer tube unit 21. In the example shown in FIG. 3, the heat transfer tube unit 21 is configured by combining the connection shaft 51 with one heat transfer tube 22. Further, an example in which the heat transfer tube unit 21 is configured by combining a plurality of, for example, two heat transfer tubes 22 on one connecting shaft 51 will be described later.

  FIG. 4 is a plan view schematically showing the case where the heat transfer tube 22 is removed for convenience and the dust removing device 50 is observed from above. In the present embodiment, since one connecting shaft 51 is connected to one heat transfer tube 22, the casing 11 is arranged along the arrangement direction A as shown in FIG. 4. A plurality of connecting shafts 51 and striking means 55 are arranged. As shown in FIG. 4, the drive shaft 57 coupled to each striking means 55 may extend through the side surface 12 of the casing 11 to the outside of the casing 11. In addition, a drive device 58 that rotationally drives the drive shaft 57 may be disposed outside the casing 11.

  As shown in FIG. 4, the adjacent hitting means 55 may be coupled to the drive shaft 57 at different angles so as to hit the connecting shafts 51 at different timings. By shifting the timing of striking each connecting shaft 51, the load on the driving device 58 can be reduced. Further, it is possible to prevent a large amount of dust from being removed at a time. As a result, it is possible to reduce the load applied to the mechanism for discharging the dust and to prevent the dust discharge port from being clogged.

  Next, the connecting shaft 51 will be described in detail with reference to FIG. FIG. 5 is a perspective view showing the connecting shaft 51 and the heat transfer tube 22 connected to the connecting shaft 51. Although the specific structure of the connecting shaft 51 is not particularly limited, for example, the connecting shaft 51 may be formed of a square pipe. In the example shown in FIG. 5, one end of the connecting portion 52 is fixed to the upper surface of the square pipe that constitutes the connecting shaft 51, and the other end of the connecting portion 52 is folded down on the lower side of the heat transfer tube 22 through the contact plate 53. It is fixed to the part 25. In addition, as long as the striking force along the axial direction of the connecting shaft 51 can be appropriately applied to the heat transfer tube 22, a specific method for connecting the connecting shaft 51 and the heat transfer tube 22 is particularly limited. There is no. For example, although not shown, the connecting shaft 51 may be connected to the straight tube portion 23 or the upper folded portion 24 of the heat transfer tube 22. As shown in FIG. 5, the head 54 may be fixed to the connecting shaft 51. In this case, the head 54 is hit by the hitting means 55, and as a result, the hitting force is transmitted to the heat transfer tube 22 via the head 54, the connecting shaft 51, the connecting portion 52, and the contact plate 53.

  Next, the above-described support mechanism 30 will be described in detail with reference to FIGS. 3 and 6. As shown in FIG. 6, the support mechanism 30 is coupled to the main body 31 and the main body 31 that extend in the vicinity of the plurality of straight pipe portions 23 of the heat transfer tube 22. A plurality of grip portions 32 for gripping the straight tube portion 23 of the heat transfer tube 22. By using such a support mechanism 30, each heat transfer tube 22 can be suspended from above in the horizontal heat exchanger 20. The support mechanism 30 can also position the heat transfer tube 22 in the horizontal direction.

  In the case of a conventional type dust removing device in which a plurality of heat transfer tubes are connected along a direction orthogonal to the heat transfer tube panel surface, vibration occurs in a direction orthogonal to the heat transfer tube panel surface. In this case, vibration is applied in the direction of low rigidity of the heat transfer tube. Accordingly, in order to prevent displacement or breakage of the heat transfer tube due to vibration, it is necessary to take measures such as strengthening the support structure. On the other hand, in the present embodiment, vibration is applied to the heat transfer tube 22 in a direction in which the heat transfer tube 22 has high rigidity (in-plane direction of the heat transfer tube panel surface). Therefore, the displacement of the heat transfer tube 22 in the direction orthogonal to the heat transfer tube panel surface is small. For this reason, it is possible to prevent displacement of the heat transfer tube 22 due to vibration and to secure support of the heat transfer tube 22 using a relatively simple support structure. The support mechanism 30 is configured in consideration of such points.

  However, in the support mechanism 30 shown in FIGS. 3 and 6, the plurality of heat transfer tubes 22 are suspended from above, and the lower portion of the heat transfer tubes 22 is not particularly supported. Therefore, the position of the heat transfer tube 22 is displaced in the arrangement direction A due to vibration or the like when the striking force is applied, and as a result, there is no possibility that the two adjacent heat transfer tubes 22 come into contact with each other. I can not say. In order to prevent such contact, preferably, as shown in FIG. 7, the distance between the adjacent heat transfer tubes 22 in the pair of adjacent heat transfer tubes 22 in the arrangement direction A is greater than or equal to the arrangement interval S provided in advance. An interval holding mechanism 40 is provided for maintenance. Thereby, even when the heat transfer tube 22 is displaced in the arrangement direction A, it is possible to prevent the two adjacent heat transfer tubes 22 from coming into contact with each other. As shown in FIG. 7, the arrangement method of the plurality of heat transfer tubes 22 in the present embodiment is a lattice arrangement.

  FIG. 8 is a perspective view showing an example of the configuration of the interval holding mechanism 40. In the example shown in FIG. 8, the interval holding mechanism 40 includes a first spacer 41 attached to one of a pair of adjacent heat transfer tubes 22 and a second spacer 42 attached to the other of the pair of adjacent heat transfer tubes 22. ,have. The first spacer 41 and the second spacer 42 are configured to contact each other when the interval between the adjacent heat transfer tubes 22 in the arrangement direction A is the arrangement interval S described above. This can prevent the interval between adjacent heat transfer tubes 22 from becoming smaller than the arrangement interval S. In addition, since it is not necessary to fix the adjacent heat transfer tubes 22 to each other by welding, it is easy to arrange the heat transfer tubes 22 inside the casing 11 in the manufacturing process of the heat exchanger 20. Each of the spacers 41 and 42 may be attached to the heat transfer tube 22 via a contact plate 43.

Preferably, the longitudinal direction N ₁ end contacting the second spacer 42 of the end portion of the first spacer 41, the longitudinal direction N of the end in contact with the first spacer 41 of the end portion of the second spacer 42 ₂ are not parallel to each other. For example, as shown in FIG. 8, the longitudinal direction N ₁ of the end of the first spacer 41 extends in a vertical direction, while the longitudinal direction N ₂ end of the second spacer 42 extends in the horizontal direction. That is, the direction in which the end portion of the first spacer 41 extends is orthogonal to the direction in which the end portion of the second spacer 42 extends. Thus, by comprising the 1st spacer 41 and the 2nd spacer 42, the 1st spacer 41 and the 2nd spacer 42 can be made to contact more reliably.

  In the present embodiment, since the dust removing device 50 applies a striking force to the heat transfer tube 22 in the in-plane direction of the heat transfer tube panel surface, the heat transfer tube 22 has sufficient rigidity against vibration caused by this. Have. Therefore, the interval holding mechanism 40 may be provided not in the entire heat transfer tube 22 but only in a part of the heat transfer tube 22. For example, as illustrated in FIG. 7, the interval holding mechanism 40 may be provided only in the vicinity of both ends of the heat transfer tube panel in the exhaust gas flow direction F in the heat transfer tube 22.

(Manufacturing method of heat exchanger)
Next, the operation and effect of the present embodiment having such a configuration will be described. First, a method for manufacturing the heat exchanger 20 will be described with reference to FIGS. 9A to 9C. Here, the manufacture of the heat exchanger 20 is centered on the case of using the heat transfer tube unit 21 which is the most typical one as the heat transfer tube unit 21 and is a combination of one connecting shaft 51 and one heat transfer tube 22. A method will be described.

  First, a heat transfer tube unit forming step of forming the heat transfer tube unit 21 by connecting the connecting shaft 51 to the heat transfer tube 22 outside the casing 11 is performed. For example, as shown to FIG. 9A, the heat exchanger tube 22 is arrange | positioned on the surface plate 15 in a factory. Next, as shown in FIG. 9B, the connecting shaft 51 is connected to the plurality of lower folded portions 25 of the heat transfer tube 22 via the contact plate 53 and the connecting portion 52. As a connection method, for example, welding is used. Thus, the heat transfer tube unit 21 including the heat transfer tube 22 and the connecting shaft 51 connected to the heat transfer tube 22 can be formed in the factory. In addition, you may further implement in the factory the process of attaching the one part component of the above-mentioned space | interval holding | maintenance mechanism 40, or the above-mentioned support mechanism 30 to the heat exchanger tube 22. FIG.

  Next, as shown to FIG. 9C, the arrangement | positioning process which arrange | positions the heat exchanger tube unit 21 inside the casing 11 is implemented. Here, as described above, the connecting shaft 51 is already connected to the heat transfer tube 22 of the heat transfer tube unit 21. For this reason, it is not necessary to perform the operation | work which connects the connection shaft 51 to the heat exchanger tube 22 inside the casing 11. FIG. In general, the space inside the casing 11 is narrow, and therefore the work inside the casing 11 is less efficient than the work in the factory. Therefore, by replacing the work inside the casing 11 with the work in the factory, the number of man-hours and work periods required for manufacturing the heat exchanger 20 and the exhaust heat boiler 10 can be reduced.

  9A to 9C show an example in which the heat transfer tube units 21 are formed in the factory and the heat transfer tube units 21 are arranged one by one in the casing 11, but the present invention is not limited to this. For example, as shown in FIG. 10A, the above-described heat transfer tube unit forming step includes a heat transfer tube module forming step of forming a heat transfer tube module 26 by combining a plurality of heat transfer tube units 21, for example, two heat transfer tube units 21. Also good. Further, the heat transfer tube unit forming step may form the heat transfer tube module 26 including the two heat transfer tube units 21 by combining the plurality of heat transfer tubes 22 and the plurality of connecting shafts 51. Moreover, the above-mentioned arrangement | positioning process may include the process of arrange | positioning the heat exchanger tube unit 21 in the inside of the casing 11 with the form of the heat exchanger tube module 26. FIG. As a result, the plurality of heat transfer tube units 21 can be quickly arranged inside the casing 11, thereby further reducing the number of man-hours and work periods required for manufacturing the heat exchanger 20 and the exhaust heat boiler 10. .

(Dust removal effect)
Next, the dust removal effect of the dust removing device 50 according to the present embodiment will be described. FIG. 11 is a diagram illustrating a state of the heat transfer tube 22 when a striking force from the dust removing device 50 is applied to the heat transfer tube 22. As described above, the heat transfer tube 22 is suspended from above. For this reason, the upper end of the heat transfer tube 22 is a so-called fixed end, and the lower end of the heat transfer tube 22 is a so-called free end. Further, as described above, since the heat transfer tube 22 extends in a meandering manner in the surface of the heat transfer tube panel surface, the rigidity of the heat transfer tube 22 in the surface of the heat transfer tube panel is in a direction perpendicular to the surface, that is, the above-described surface. It is higher than the rigidity of the heat transfer tube 22 in the arrangement direction A. The dust removing device 50 is configured to apply a striking force to the heat transfer tube panel in the direction in which the heat transfer tube extends in the surface of the heat transfer tube panel, that is, in the direction in which the rigidity of the heat transfer tube 22 is high. As a result, as shown in FIG. 11, the heat transfer tube 22 is displaced and vibrates in the heat transfer tube extending direction with respect to the upper end whose free end is the fixed end. Therefore, the surface of the heat transfer tube 22 can be sufficiently vibrated between the upper end and the lower end of the heat transfer tube 22, whereby dust adhering to the surface of the heat transfer tube 22 can be sufficiently removed. In FIG. 11, the heat transfer tube 22 is exaggerated for the sake of easy understanding. Therefore, the heat transfer tube 22 does not always deform as shown in FIG.

  Next, the frequency of vibration generated in the heat transfer tube 22 when such a striking force is applied will be examined. As one of the factors that determine the frequency of vibration generated in the heat transfer tube 22, the rigidity of the heat transfer tube 22 can be considered. In general, it is known that the natural frequency of an object increases as the rigidity of the object increases. Here, as described above, the rigidity of the heat transfer tube 22 in the heat transfer tube extending direction in the heat transfer tube panel surface is higher than the rigidity of the heat transfer tube 22 in the direction A orthogonal to the heat transfer tube panel surface. Therefore, according to the present embodiment, the frequency of vibration generated in the heat transfer tube 22 can be increased by applying a striking force to the heat transfer tube 22 in the heat transfer tube extending direction. For example, vibration having a lot of frequency components of 1 kHz or more can be generated in the heat transfer tube 22.

  As a result of intensive research conducted by the present inventor, when the frequency of vibration of the heat transfer tube 22 is a frequency near 1 kHz or higher, dust adhering to the heat transfer tube 22 is efficiently removed. I found it. Here, according to the present embodiment, by applying a striking force to the heat transfer tube 22 in a direction where the rigidity of the heat transfer tube 22 is high, vibration having a lot of frequency components of 1 kHz or more can be generated in the heat transfer tube 22. Thereby, dust can be efficiently removed.

  Further, according to the present embodiment, as described above, the straight tube portion 23 of the heat transfer tube 22 is arranged vertically. For this reason, the dust adhering to the surface of the straight pipe part 23 can be removed using not only vibration but also gravity. For this reason, compared with the case of the type of heat exchanger with which the straight pipe part of a heat exchanger tube extends in a horizontal direction, dust can be removed efficiently.

The comparative embodiment Next, the effect of this embodiment will be described in comparison with a comparative embodiment. 12 and 13 are a side view and a plan view showing a dust removing device 70 according to a comparative embodiment. In the comparison form shown in FIGS. 12 and 13, the same parts as those in the present embodiment shown in FIGS.

  As shown in FIGS. 12 and 13, in the comparative embodiment, the connecting shaft 71 of the dust removing device 70 extends along the arrangement direction A in which the plurality of heat transfer tubes 22 are arranged. For this reason, as shown in FIG. 13, the striking means 73 for applying a striking force to the connecting shaft 71 applies a striking force to the connecting shaft 71 in a direction orthogonal to the heat transfer tube panel surface, that is, in a direction parallel to the arrangement direction A. It is configured as follows. In order to limit the displacement of the connecting shaft 71 in the exhaust gas flow direction F, a pair of clasps 75 are provided in the vicinity of the connecting shaft 71 as shown in FIG. The clasp 75 is fixed to a fixed shaft 74 that extends along the exhaust gas flow direction F below the connecting shaft 71.

  In the comparative embodiment, the striking means 73 is disposed outside the casing 11 due to the restriction of the space inside the casing 11. A through hole 76 is formed in the side surface 12 of the casing 11, and a rod 77 for transmitting a striking force from the striking means 73 to the connecting shaft 71 is provided in the through hole 76.

  The above-described through holes 76 are formed in the side surface 12 of the casing 11 by the same number as the number of rods 77. For this reason, in the comparative form, the air outside the casing 11 flows into the casing 11 and the temperature inside the casing 11 decreases, and as a result, the performance of the exhaust heat boiler may decrease. . Further, since the hitting means 73 is disposed outside the casing 11, a soundproof means for preventing the sound generated due to the hitting from diffusing is necessary.

  On the other hand, according to the present embodiment, the connecting shaft 51 extends along the heat transfer tube extending direction of the heat transfer tube panel surface. For this reason, the connecting shaft 51 and the striking means 55 can be arranged inside the casing 11. Therefore, the number of through holes formed in the side surface 12 of the casing 11 can be reduced, and thereby the performance of the exhaust heat boiler 10 can be enhanced. Moreover, the man-hour and time required for forming the through hole can be reduced. In addition, no soundproofing means is required, and therefore the number of man-hours and work periods can be further reduced.

  In the comparative embodiment, the gap between the through holes 76 is closed by the packing 78 in order to prevent air from flowing into the casing 11. In this case, the striking force applied to the rod 77 from the striking means 73 is attenuated by the frictional force between the rod 77 and the packing 78. For this reason, the striking force transmitted to the connecting shaft 71 is reduced, and as a result, it is considered that the dust adhering to the heat transfer tube 22 cannot be sufficiently removed.

  On the other hand, according to the present embodiment, the connecting shaft 51 and the striking means 55 are both arranged inside the casing 11, and therefore, when the striking force is transmitted from the striking means 55 to the connecting shaft 51. Loss can be reduced. Thereby, the dust adhering to the heat transfer tube 22 can be efficiently removed.

  In the comparative embodiment, as shown in FIG. 13, one connecting shaft 71 is connected to a large number of heat transfer tubes 22. For this reason, it is necessary to connect the connecting shaft 71 to the heat transfer tube 22 while precisely adjusting the positions of the numerous heat transfer tubes 22. For example, it is necessary to connect the connecting shaft 71 to the heat transfer tube 22 in a narrow region existing below the large number of heat transfer tubes 22 installed in the casing 11 and suspended from above. On the other hand, in the comparative embodiment, the heat transfer tube 22 is connected to the casing 11 with the connecting shaft 71 attached to the large number of heat transfer tubes 22, that is, with the connecting shaft 71 and the large number of heat transfer tubes 22 being integrated. It is very difficult to carry it in and install it from the factory to the site. Therefore, in the comparative embodiment, the operation of connecting the connecting shaft 71 to the heat transfer tube 22 is performed not in the factory but in the casing 11. For this reason, the man-hour and time required for manufacture of a heat exchanger and a waste heat boiler will become large.

  On the other hand, according to the present embodiment, the connecting shaft 71 extends along the heat transfer tube extending direction. For this reason, the operation | work which connects the connection axis | shaft 51 to the heat exchanger tube 22 and forms the heat exchanger tube unit 21 can be implemented outside the casing 11. Thereby, the man-hour and work period which are required for manufacture of the heat exchanger 20 and the exhaust heat boiler 10 can be reduced.

  In the comparative embodiment, a large number of heat transfer tubes 22 are connected to each other by a connecting shaft 71. For this reason, for example, when some of the heat transfer tubes 22 are damaged, it is difficult to take out only the damaged heat transfer tubes 22 to the outside of the casing 11. Accordingly, all of the large number of heat transfer tubes 22 connected to each other by the connecting shaft 71 are exchanged. As a result, the cost required for repairing the exhaust heat boiler 10 increases.

  On the other hand, according to the present embodiment, only the damaged heat transfer tube 22 or only the damaged heat transfer tube module 26 can be easily taken out. For this reason, the cost required for repairing the exhaust heat boiler 10 can be reduced.

  Next, the dust removal effect of the dust removing device 70 according to the comparative embodiment will be described. 14A and 14B are views showing the state of the heat transfer tube 22 when the striking force from the dust removing device 70 is applied to the connecting shaft 71. FIG.

  In the comparative form, the connecting shaft 71 extends along the arrangement direction A, and the striking means 73 is configured to apply a striking force to the connecting shaft 71 in a direction parallel to the arrangement direction A. Here, as described above, the rigidity of the heat transfer tube 22 in the arrangement direction A, that is, the direction orthogonal to the heat transfer tube panel surface is smaller than the rigidity of the heat transfer tube 22 in the in-plane direction of the heat transfer tube panel surface. In this case, the striking force applied to the connecting shaft 71 acts to integrally displace the plurality of heat transfer tubes 22 as indicated by an arrow B in FIG. 14B. Therefore, in the comparative form, the surface of the heat transfer tube 22 cannot be sufficiently vibrated, and therefore, it is considered that the dust attached to the surface of the heat transfer tube 22 cannot be sufficiently removed.

  On the other hand, according to the present embodiment, the dust removing device 50 is configured to apply a striking force to the heat transfer tube panel in a direction in which the heat transfer tube 22 has high rigidity. For this reason, the dust adhering to the surface of the heat transfer tube 22 can be sufficiently removed.

Modifications of the present embodiment Various modifications can be made to the above-described embodiment. Hereinafter, an example of modification will be described with reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above embodiment are used for the parts that can be configured in the same manner as in the above embodiment. A duplicate description is omitted.

(Modification example of support column)
In FIG. 1, an example in which the support column 13 that supports the casing 11 from the side is disposed between the heat exchangers 20 is shown. However, in the present embodiment, the connecting shaft 51 and the hitting means 55 are arranged inside the casing 11 as described above. Therefore, it is not necessary to form a large number of through holes in the side surface 12 of the casing 11. For this reason, compared with the case of the above-mentioned comparative form, the dimension and arrangement | positioning of the support | pillar 13 can be determined freely. For example, as shown in FIG. 15, at least a part of the plurality of columns 13 can be arranged so as to overlap the heat transfer tube 22 of the heat exchanger 20 when viewed from the side. Therefore, the dimensions of the support columns 13 and the casing 11 can be optimized as a whole, which can reduce the number of the support columns 13 and the overall weight of the support columns 13 and the casing 11. . For this reason, the cost of the exhaust heat boiler 10 can be reduced.

(Modification of connecting shaft)
In the above-described embodiment, an example in which one heat transfer tube 22 is connected to one connection shaft 51 has been described. However, the present invention is not limited to this, and a plurality of heat transfer tubes 22 may be connected to one connecting shaft 51. For example, as shown in FIG. 16, two heat transfer tubes 22 may be connected to the connecting shaft 51. In this case, the heat transfer tube module 26 may be configured by using the plurality of heat transfer tubes 22 connected to one connection shaft 51 as one unit.

(Modification of hitting means)
In the above-described embodiment, an example in which one hitting means 55 is provided for one connecting shaft 51 is shown, but the present invention is not limited to this. For example, as shown in FIG. 17, the striking means 55 may be configured such that one striking means 55 applies a striking force to a plurality of connecting shafts 51, for example, two connecting shafts 51.

(Modification of support mechanism)
In the above-described embodiment, an example in which the support mechanism 30 includes one main body portion 31 and a plurality of gripping portions 32 has been described. However, the present invention is not limited to this. FIG. 18 is a side view showing a modified example of the support mechanism 30, and FIG. 19 is a longitudinal sectional view showing the support mechanism 30 of FIG. 18 viewed from the XIX-XIX direction. In the example shown in FIGS. 18 and 19, the support mechanism 30 is coupled to the main body portion 33 that extends in the vicinity of the plurality of upper folded portions 24 of the heat transfer tube 22, and the upper folded portion 24. A lower support portion 34 that is supported from above, and an upper support portion 35 that is in contact with the upper folded portion 24 from above. The upper support part 35 is configured such that one upper support part 35 contacts the plurality of upper folded parts 24. The lower support portion 34 has a contour adapted to the contour of the lower portion of the upper folded portion 24 of the heat transfer tube 22. A plurality of cutout portions 35 a each having a contour adapted to the contour of the upper portion of the upper folded portion 24 of the heat transfer tube 22 are formed at the lower end of the upper support portion 35. Therefore, the upper folded portion 24 of the heat transfer tube 22 can be stably supported in the vertical direction.

  Although the specific shape of the support mechanism 30 according to the present modification is not particularly limited, for example, as shown in FIG. 19, the main body portion 33 and the upper support portion 35 may be made of angle steel. In this case, one end of the angle steel constituting the upper support portion 35 is in contact with the upper folded portion 24, and the other end of the angle steel is disposed on the angle steel constituting the main body portion 33. Further, as shown in FIG. 19, one end of the angle steel constituting the upper support portion 35 is disposed so as to fix the horizontal position of the upper folded portion 24 with the main body portion 33.

  Next, an example of a method for forming the support mechanism 30 according to the present modification will be described with reference to FIGS. 20A and 20B. First, the main body 33 is prepared, and then, as shown in FIG. 20A, a plurality of lower support portions 34 are attached to the main body 33 by, for example, welding. Next, as shown in FIG. 20B, the heat transfer tubes 22 are prepared, and then the corresponding upper folded portions 24 are brought into contact with the lower support portions 34. Next, the upper support portion 35 is brought into contact with each upper folded portion 24, and then the upper support portion 35 is attached to the main body portion 33 by welding, for example. As described above, according to the present modification, the step of attaching the plurality of lower support portions 34 to the main body portion 33 can be performed before the heat transfer tube 22 is prepared. For this reason, compared with the case where the lower side support part 34 is attached to the main-body part 33, adjusting the position with respect to the heat exchanger tube 22, the man-hour and work period which an attachment process requires can be reduced. Further, the upper support part 35 is configured such that one upper support part 35 contacts the plurality of upper folded parts 24. For this reason, compared with the case where one upper side support part is needed for one upper return part 24, the man-hour and time required for the process of attaching the upper side support part 35 to the main-body part 33 can be reduced.

(Other variations of support mechanism)
Further, in the above-described embodiment and modification examples, one support mechanism 30 supports one heat transfer tube 22. However, the present invention is not limited to this, and one support mechanism 30 may support a plurality of heat transfer tubes 22. Hereinafter, an example in which one support mechanism 30 supports two heat transfer tubes 22 will be described with reference to FIG.

  A support mechanism 30 shown in FIG. 21 is an embodiment that simultaneously supports two adjacent heat transfer tubes 22. The main body 33 passes through the vicinity of the plurality of upper folded portions 24 of the one heat transfer tube 22 located on one side of the main body 33 and the other heat transfer tube 22 located on the other side of the main body 33. The plurality of upper folded portions 24 extend in the vicinity. The main body 33 is made of, for example, T-shaped steel, and passes through the upper folded portion 24 of the single heat transfer tube 22 on both sides of the central common wall that is symmetrical. Further, the lower support portion is coupled to the main body portion 33 on one side, and is connected to the lower support portion 34 that supports the upper folded portion 24 of the one heat transfer tube 22 from below, and the main body portion 33 on the other side. The other lower support portion 34 that is coupled and supports the upper folded portion 24 of the other heat transfer tube 22 from below. The upper support portion is coupled to the main body portion 33 on one side, and is coupled to the upper support portion 35 that comes into contact with the upper folded portion 24 of the one heat transfer tube 22 from above and the main body portion 33 on the other side. And the other upper support portion 35 that contacts the upper folded portion 24 of the other heat transfer tube 22 from above. In addition, one upper support portion 35 is configured such that one upper support portion 35 is in contact with the plurality of upper folded portions 24 of one heat transfer tube 22, and the other upper support portion 35 is configured as one upper support portion 35. The support portion 35 is configured to contact the plurality of upper folded portions 24 of the other heat transfer tube 22. By configuring the support mechanism 30 in this way, the two heat transfer tubes 22 can be stably supported in the vertical direction using one support mechanism 30. In this case, the heat transfer tube module 26 may be configured with a plurality of heat transfer tubes 22 supported by one support mechanism 30 as one unit.

In the case of the staggered arrangement and the above-described embodiment and modification, the case where the arrangement method of the plurality of heat transfer tubes 22 is the lattice arrangement has been described. However, the arrangement method is not limited to this, and the arrangement method of the plurality of heat transfer tubes 22 may be a staggered arrangement. Hereinafter, with reference to FIGS. 22 to 25, an example in which a staggered arrangement is adopted will be described.

(Spacing mechanism)
First, an example of the interval holding mechanism 40 used in the case of the staggered arrangement will be described. 22 and 23 are a cross-sectional view and a perspective view showing an example of the interval holding mechanism 40. FIG.

  When the staggered arrangement is adopted, preferably, as shown in FIG. 22, the heat transfer tube module 26 is formed by combining two adjacent heat transfer tube units 21. In this case, the two heat transfer tube units 21 included in the heat transfer tube module 26 are coupled to each other by the coupling mechanism 45. Therefore, in this modification, the interval holding mechanism 40 that maintains the interval between the two heat transfer tubes 22 in the arrangement direction A to be equal to or larger than the predetermined arrangement interval S is disposed between the pair of opposed heat transfer tube modules 26. It only has to be.

  For example, as shown in FIG. 23, the coupling mechanism 45 includes a connecting rod 46 connected to the pair of heat transfer tubes 22 via a backing plate 47. A method for connecting the connecting rod 46 to the contact plate 47 is not particularly limited, but, for example, welding is employed. As a result, the two heat transfer tubes 22 included in the heat transfer tube module 26 can be firmly connected to each other. Such a connection operation may be performed on the surface plate 15 in the same manner as the operation of connecting the connection shaft 51 to the heat transfer tube 22.

(Support mechanism)
Even when the staggered arrangement is adopted, the support mechanism 30 is configured such that one support mechanism 30 supports the two heat transfer tubes 22 in the vertical direction as in the case of the lattice arrangement shown in FIG. It may be. In the case of the staggered arrangement, the position of the upper folded portion 24 of one heat transfer tube 22 and the position of the upper folded portion 24 of the other heat transfer tube 22 are shifted in the exhaust gas flow direction F. Accordingly, in FIG. 24, the upper folded portion 24 and the lower support portion 34 of the other heat transfer tube 22 are indicated by a one-dot chain line.

(Connection shaft)
Also in the case where the staggered arrangement is adopted, the two heat transfer tubes 22 may be connected to the connecting shaft 51 as in the case of the lattice arrangement shown in FIG.

  In addition, although some modified examples with respect to the above-described embodiment have been described, naturally, a plurality of modified examples can be applied in combination as appropriate.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited to this Example.

  In the horizontal heat exchanger 20, the characteristics of vibration generated in the heat transfer tube 22 by the impact force from the dust removing device were evaluated by simulation. As the dust removing device 50, an apparatus including a connecting shaft 51 extending in the exhaust gas flow direction F and connected to the vicinity of the upper end of one heat transfer tube 22 was set. The acceleration generated in the heat transfer tube 22 was calculated in the X direction, the Y direction, and the Z direction. The sampling interval was 12 kHz. As the coordinate system, a right-hand coordinate system is set in which the axial direction of the connecting shaft 51 is the Y direction and the vertical direction is the Z direction. In the Y direction, the direction of hitting the connecting shaft 51 is a positive direction. In the Z direction, the upward direction is a positive direction.

  The calculation results of the acceleration frequency in the X direction, the Y direction, and the Z direction are shown in FIGS. 26 (a), (b), and (c), respectively. As can be seen from the figure, the frequency component centered at 1 kHz was dominant. Many high frequency components exceeding 1 kHz were also generated.

(Comparative example)
Except for setting the dust removing device 70 provided with a connecting shaft 71 extending in the arrangement direction A and connected in the vicinity of the upper ends of the plurality of heat transfer tubes 22 formed in a meandering manner in the vertical cross section. Similarly to the example, the characteristics of vibration generated in the heat transfer tube 22 by the impact force from the dust removing device were evaluated by simulation. The calculation results of the acceleration frequency in the X direction, the Y direction, and the Z direction are shown in FIGS. 27A, 27B, and 27C, respectively.

  As can be seen from the comparison between FIGS. 26 (a), (b), and (c) and FIGS. 27 (a), (b), and (c), the high frequency component exceeding 1 kHz is generated more in the example than in the comparative example. Was. Thus, according to the Example, the frequency of the generated vibration could be increased by applying a striking force to the heat transfer tube panel in a direction in which the heat transfer tube 22 has high rigidity.

DESCRIPTION OF SYMBOLS 10 Waste heat boiler 11 Casing 13 Support | pillar 14 Hopper 15 Surface plate 20 Heat exchanger 21 Heat transfer tube unit 22 Heat transfer tube 23 Straight pipe part 24 Upper folding part 25 Lower folding part 26 Heat transfer tube module 30 Support mechanism 33 Main body part 34 Lower side Support part 35 Upper support part 35a Notch part 40 Spacing mechanism 41 First spacer 42 Second spacer 50 Dust removing device 51 Connecting shaft 55 Blowing means

Claims (15)

A heat exchanger that heats a heat medium using heat of a gas containing dust flowing inside a casing,
A heat transfer tube disposed inside the casing and through which the heat medium passes;
A connecting shaft connected to a plurality of portions of the heat transfer tube;
A dust removing device for removing dust adhering to the heat transfer tube,
The heat transfer tube has a straight tube portion and a folded portion, and the straight tube portion and the folded portion are alternately arranged so that the heat transfer tube extends in a meandering manner in a plane,
The dust removing device is a heat exchanger having striking means for applying striking force to the connecting shaft.   The heat exchanger according to claim 1, wherein the connection shaft is connected to an outermost portion of the folded portion of the heat transfer tube. The plane on which the heat transfer tubes are arranged in a serpentine shape is parallel to the gas flow direction,
The heat exchanger according to claim 1 or 2, wherein the straight pipe portion of the heat transfer pipe is arranged to extend in a vertical direction.   The heat exchanger according to any one of claims 1 to 3, wherein the connecting shaft and the striking means are disposed inside the casing. The heat exchanger is a horizontal heat exchanger in which gas flows in a horizontal direction,
The casing is supported from the side by a plurality of pillars extending in the vertical direction,
5. The heat exchanger according to claim 1, wherein at least some of the plurality of columns are arranged so as to overlap the heat transfer tube when viewed from a side. Including the heat transfer tube, a plurality of heat transfer tubes are arranged along an arrangement direction orthogonal to the plane in which the heat transfer tubes are formed in a meandering shape,
The pair of the heat transfer tubes adjacent in the arrangement direction is provided with a space holding mechanism for maintaining a space between the adjacent heat transfer tubes to be equal to or larger than a predetermined arrangement space. The heat exchanger as described in any one of. The spacing mechanism includes a first spacer attached to one of the pair of heat transfer tubes adjacent in the arrangement direction, and a second spacer attached to the other of the pair of adjacent heat transfer tubes,
The heat exchanger according to claim 6, wherein the first spacer and the second spacer are configured to contact each other when a distance between the pair of heat transfer tubes in the arrangement direction is the arrangement interval. .   The longitudinal direction of the end portion of the first spacer that contacts the second spacer is not parallel to the longitudinal direction of the end portion of the second spacer that contacts the first spacer. The heat exchanger according to claim 7. The heat exchanger is a horizontal heat exchanger in which gas flows in a horizontal direction,
The folded portion of the heat transfer tube includes an upper folded portion connected to the upper ends of two adjacent straight tube portions, and a lower folded portion connected to the lower ends of the two adjacent straight tube portions. ,
The heat transfer tube extends along the extending direction of the heat transfer tube, and is attached with a support mechanism that supports the heat transfer tube in the vertical direction.
The support mechanism includes a main body portion extending so as to pass near a plurality of upper folded portions of the heat transfer tube, a lower support portion coupled to the main body portion and supporting the upper folded portion from below, and the upper folded portion. An upper support part that comes into contact with the part from above,
The heat exchanger according to any one of claims 1 to 8, wherein the upper support portion is configured such that one upper support portion contacts a plurality of the upper folded portions.   10. The heat exchanger according to claim 9, wherein a plurality of cutout portions each of which is adapted to a contour of the upper folded portion are formed at a lower end of the upper support portion of the support mechanism. Including the heat transfer tube, a plurality of heat transfer tubes are arranged along an arrangement direction orthogonal to the plane in which the heat transfer tubes are formed in a meandering shape,
The main body portion of the support mechanism passes through the vicinity of the plurality of upper folded portions of one of the heat transfer tubes located on one side of the main body portion, and the other of the main body portions located on the other side of the main body portion. Extending through the vicinity of the plurality of upper folded portions of the heat transfer tube,
The lower support portion is coupled to the main body portion, and is coupled to the lower main support portion for supporting the upper folded portion of the one heat transfer tube from below and the main body portion, and the other heat transfer tube And the other lower support part that supports the upper folded part from below,
The upper support part is coupled to the main body part, and is connected to the upper folding part of the one heat transfer tube from above, and the upper support part is coupled to the main body part and the upper side of the other heat transfer tube. And the other upper support part that contacts the folded part from above,
The one upper support portion is configured such that one upper support portion is in contact with the plurality of upper folded portions of the one heat transfer tube,
The heat exchanger according to claim 9 or 10, wherein the other upper support portion is configured such that one upper support portion contacts a plurality of the upper folded portions of the other heat transfer tube. A dust removing device that is provided in the heat exchanger according to claim 1 and removes dust adhering to the heat transfer tube,
A dust removing device comprising striking means for applying striking force to the connecting shaft of the heat exchanger. An exhaust heat boiler that recovers heat from exhaust gas containing dust,
A casing,
A heat exchanger that is disposed inside the casing and heats a heat medium using heat of exhaust gas flowing inside the casing.
The said heat exchanger is a waste heat boiler which consists of a heat exchanger of Claim 1. It is a manufacturing method of the heat exchanger of Claim 1, Comprising:
A heat transfer tube unit forming step of forming a heat transfer tube unit by connecting the connection shaft to the heat transfer tube outside the casing;
An arrangement step of arranging the heat transfer tube unit inside the casing. In the heat exchanger, including the heat transfer tubes, a plurality of heat transfer tubes are arranged along an arrangement direction orthogonal to a plane in which the heat transfer tubes are formed in a meandering shape,
The heat transfer tube unit formation step includes a step of forming a heat transfer tube module by combining a plurality of the heat transfer tube units,
The method of manufacturing a heat exchanger according to claim 14, wherein the arranging step includes a step of arranging the heat transfer tube unit in the casing in the form of the heat transfer tube module.