Heat exchange device

Abstract

To provide a heat exchange device that can restrain condensation on a member surface constituting the heat exchange device when exhaust gas in which a corrosive component is contained passes through a heat exchange part.SOLUTION: A heat exchange device 1 comprises a heat exchange part 20 through which exhaust gas flows, a casing 10 housing the heat exchange part 20, and a plurality of flow passage formation members 30 blocking at least a portion of a gap between the heat exchange part 20 and the casing 10. The plurality of flow passage formation members 30 comprises a first flow passage formation member 31 arranged on one end side of the heat exchange part 20, a second flow passage formation member 32 arranged on the other end side of the heat exchange part 20, and a third flow passage formation member 33 arranged between the other end side of the heat exchange part 20 and an exhaust gas outlet 12 of the casing 10. The second flow passage formation member 32 forming an exhaust gas introduction part 41, and the third flow passage formation member 33 forming an exhaust gas flow part 42 are arranged at different positions when viewed in a flow direction of the exhaust gas flowing in a wall member 23 of the heat exchange part 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a heat exchange device. [Background technology]

[0002] Conventionally, as a combustion system for sludge, etc., a system has been proposed in which heat from exhaust gas is recovered and used to preheat the combustion air (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-220545 A Summary of the Invention [Problem to be solved by the invention]

[0004] The exhaust gas used in the heat exchanger of such an exhaust gas boiler system contains corrosive components, and therefore, if the temperature of the exhaust gas flowing through the heat exchanger drops below the dew point, the corrosive components will condense, and the condensed corrosive components may corrode the components that make up the heat exchanger.

[0005] An object of the present invention is to provide a heat exchanger capable of suppressing condensation on the surfaces of components constituting the heat exchanger when exhaust gas containing corrosive components passes through a heat exchange section. [Means for solving the problem]

[0006] The present invention provides a heat exchanger comprising a heat exchanger section through which exhaust gas flows, a casing that houses the heat exchanger section, and a plurality of flow path forming members that are disposed within the casing and block at least a portion of a gap between the heat exchanger section and the casing, the heat exchanger section comprising a heat transfer tube and a wall member that separates the exhaust gas flowing through the heat exchanger section from the exhaust gas flowing inside the casing, the casing comprising an exhaust gas inlet disposed on one end side of the casing and through which exhaust gas is supplied, and an exhaust gas outlet through which exhaust gas flowing through a space formed by the wall member of the heat exchanger section and the casing is discharged, the plurality of flow path forming members being disposed on one end side of the heat exchanger section, blocking the entire surface of the gap between the casing and the wall member of the heat exchanger section, the exhaust gas inlet of the first passage forming member and the exhaust gas flow path forming member of the third passage forming member are disposed in a direction parallel to the wall member of the heat exchange unit, and the exhaust gas inlet of the second passage forming member and the exhaust gas flow path forming member of the third passage forming member are disposed in a direction parallel to the wall member of the heat exchange unit, and the exhaust gas inlet of the second passage forming member and the exhaust gas flow path forming member of the third passage forming member are disposed in different positions when viewed in a flow direction of the exhaust gas flowing through the wall member of the heat exchange unit.

[0007] The wall member may be cylindrical, the heat transfer tube may have a bent portion, and the bent portion of the heat transfer tube may be disposed outside the cylindrical wall member.

[0008] The casing may be cylindrical, and the heat exchange portion may be rectangular prism-shaped.

[0009] In addition, in a vertical cross section in the flow direction of the exhaust gas within the heat exchange section, it is preferable that the area of ​​the vertical cross section formed by the inner surface of the wall member is 40% or more and 60% or less of the area of ​​the vertical cross section formed by the inner surface of the casing.

[0010] The present invention relates to an incineration facility that includes an incinerator and the heat exchange device, and introduces exhaust gas generated in the incinerator into the heat exchange device. Effect of the Invention

[0011] According to the present invention, the heat exchange device can suppress condensation on the surfaces of the components constituting the heat exchange device when exhaust gas containing corrosive components passes through the heat exchange section. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing a heat exchange device according to a first embodiment of the present invention. [Diagram 2] FIG. 1 is a front view of a heat exchange device according to a first embodiment of the present invention. [Diagram 3] FIG. 1 is a plan view of a heat exchanger according to a first embodiment of the present invention. [Figure 4] 3 is a view showing a cross section of a second flow passage forming member of the heat exchanger according to the first embodiment of the present invention. FIG. [Diagram 5] 3 is a view showing a cross section of a third flow path forming member of the heat exchanger according to the first embodiment of the present invention. FIG. [Figure 6] FIG. 4 is a front view of a heat exchanger according to a second embodiment of the present invention. [Figure 7] FIG. 4 is a plan view of a heat exchanger according to a second embodiment of the present invention. [Figure 8] 6 is a view showing a cross section of a second flow passage forming member of a heat exchanger according to a second embodiment of the present invention. FIG. [Figure 9] 10 is a view showing a cross section of a third flow path forming member A of a heat exchanger according to a second embodiment of the present invention. FIG. [Figure 10] 10 is a view showing a cross section of a third flow path forming member B of a heat exchanger according to a second embodiment of the present invention. FIG. [Figure 11] FIG. 2 is a diagram showing the layout of the exhaust gas boiler system of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, a heat exchanger 1 according to the present invention in an exhaust gas boiler system will be described with reference to the drawings. The exhaust gas includes exhaust gas discharged from a prime mover, and waste gas generated by burning biomass fuel and industrial waste (sludge, waste plastic, etc.).

[0014] First, a heat exchanger 1 according to a first embodiment will be described with reference to FIGS. Fig. 1 is a perspective view showing a heat exchanger 1 according to a first embodiment of the present invention. The heat exchanger 1 of this embodiment is a heat exchanger that recovers heat from exhaust gas in a heat transfer tube to heat water and generate steam, and supplies the steam to a load device (not shown). Hereinafter, the heat transfer tube of the heat exchanger 1 according to the first embodiment will be referred to as a water tube. Note that Figs. 2 and 3 omit the illustration of the water tube 21 shown in Fig. 1.

[0015] As shown in FIG. 1, the heat exchange device 1 includes a casing 10, a heat exchange section 20, and a plurality of flow path forming members 30.

[0016] The casing 10 constitutes the outer shape of the heat exchanger 1. In the first embodiment, the casing 10 is formed in a cylindrical shape, the axial direction of the cylindrical shape is disposed along the vertical direction, one end (upper end) is open, and the other end (lower end) is closed. The casing 10 includes an exhaust gas inlet 11 and an exhaust gas outlet 12.

[0017] The exhaust gas inlet 11 is disposed at one end in the longitudinal direction of the casing 10. In this embodiment, the exhaust gas inlet 11 is configured by opening one end of the casing 10. The exhaust gas outlet 12 is disposed on a side surface of the casing 10 closer to one end (upper end) than the center in the longitudinal direction.

[0018] The heat exchanger 20 is housed inside the casing 10. The heat exchanger 20 includes a water pipe 21 and a wall member 23. The heat exchanger 20 of this embodiment has a rectangular prism shape.

[0019] The water pipe 21 includes a plurality of straight pipe sections 211 and a plurality of bent pipe sections 212, and allows water to flow therethrough. The straight pipe sections 211 are arranged in parallel in the horizontal direction, and are arranged in a plurality of stages in the vertical direction. One end side of the straight pipe sections 211 in the lowest stage and one end side of the straight pipe section 211 in the highest stage among the straight pipe sections 211 extend to the outside of the casing 10 through the casing 10. In this embodiment, the straight pipe sections 211 are arranged in the cylindrical casing 10 so as to extend in a direction perpendicular to a straight line connecting the center of the casing 10 and the position where the exhaust gas outlet 12 is formed. In addition, the water pipe 21 closest to the exhaust gas inlet 11 is arranged at a position higher than the exhaust gas outlet 12 in the height direction.

[0020] The multiple bent portions 212 connect the ends of two straight pipe sections 211 adjacent in the vertical direction. Specifically, the bent portions 212 connect the end side of the multiple straight pipe sections 211 in the lowest stage to the other end of the multiple straight pipe sections 211 adjacent above the straight pipe section 211 in the lowest stage. The bent portions 212 also connect one end of the multiple straight pipe sections 211 adjacent above to one end of the multiple straight pipe sections 211 adjacent above these multiple straight pipe sections 211. In this way, the straight pipe sections 211 arranged in multiple stages in the vertical direction are connected in series.

[0021] The wall member 23 separates the internal space of the casing 10 and holds the water pipe 21. In this embodiment, the wall member 23 is configured in a rectangular prism shape with a pair of open end faces. The wall member 23 is disposed inside the casing 10 so that the open end faces are aligned in the vertical direction, and is joined to the casing 10 by welding or the like via a connecting member (not shown). The length of the diagonal line of the wall member 23 in a plan view is set to be slightly smaller than the diameter of the inner peripheral surface of the casing 10. As a result, a gap is formed between the corners of the wall member 23 in a plan view and the inner surface of the casing 10.

[0022] A pair of side surfaces of the wall member 23 are each formed with a plurality of through holes through which the straight pipe portion 211 of the water pipe 21 penetrates, and the straight pipe portion 211 is inserted near both ends into the plurality of through holes. As a result, the plurality of bent portions 212 are disposed in gaps formed between the inner surface of the casing 10 and the outer surface of the wall member 23.

[0023] The plurality of flow path forming members 30 include a first flow path forming member 31 , a second flow path forming member 32 , and a third flow path forming member 33 .

[0024] 2 and 3, the first flow path forming member 31 is disposed at the upper end of the heat exchange section 20 (wall member 23) and closes a gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. More specifically, the first flow path forming member 31 is joined by welding, bolts, or the like to an upper end side of the wall member 23 that is rectangular in plan view. As a result, the first flow path forming member 31 comes close to an arc side that corresponds to the inner circumferential surface of the casing 10, thereby closing the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. According to the above-described first flow path forming member 31, the exhaust gas introduced from the exhaust gas inlet 11 is less likely to penetrate into the gap formed between the inner surface of the casing 10 and the outer surface of the heat exchange section 20 (wall member 23), and is introduced into the interior of the heat exchange section 20.

[0025] As shown in FIG. 2 and FIG. 4, the second flow passage forming member 32 is disposed on the lower end side of the heat exchanger 20 (wall member 23) and closes a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. In this embodiment, the second flow passage forming member 32 closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 at the lower end of the heat exchanger 20. More specifically, the second flow passage forming member 32 is composed of a plurality of plate-shaped members having arc sides and chord sides and plate-shaped members obtained by dividing the plate-shaped members in half, similar to the first flow passage forming member 31. The arc sides of the second flow passage forming member 32 are joined to the inner circumferential surface of the casing 10 and the chord sides are joined to the wall member 23 by welding, bolts, or the like. As a result, the second flow passage forming member 32 closes a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 by being close to the arc side corresponding to the inner circumferential surface of the casing 10 and the chord side corresponding to the wall member 23. In this embodiment, the second flow path forming member 32 fills half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, on the side opposite to the side on which the exhaust gas outlet 12 is formed.

[0026] According to the above-described second flow passage forming member 32, the exhaust gas introduced into the heat exchange section 20 is introduced downward from the lower end of the heat exchange section 20 (wall member 23), then changes direction at the lower surface of the casing 10, and is introduced into a gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 that is not blocked by the second flow passage forming member 32, and rises. That is, the second flow passage forming member 32 blocks a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, thereby forming an exhaust gas introduction section 41 that introduces the exhaust gas that has passed through the inside of the heat exchange section 20 (wall member 23) into the gap formed between the inner surface of the casing 10 and the outer surface of the heat exchange section 20 (wall member 23).

[0027] As shown in Figs. 2 and 5, the third flow passage forming member 33 is disposed below the exhaust gas outlet 12 and above the second flow passage forming member 32, and closes a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. In this embodiment, the third flow passage forming member 33 closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 between the exhaust gas outlet 12 and the second flow passage forming member 32. More specifically, the third flow passage forming member 33 is composed of a plurality of plate-shaped members having arc sides and chord sides, and plate-shaped members obtained by dividing the plate-shaped members in half, similar to the first flow passage forming member 31 and the second flow passage forming member 32. The third flow passage forming member 33 is joined by welding, bolts, etc., with the arc sides being joined to the inner circumferential surface of the casing 10 and the chord sides being joined to the wall member 23. As a result, the third flow path forming member 33 is close to the arc edge corresponding to the inner surface of the casing 10 and the chord edge corresponding to the wall member 23, thereby blocking a portion of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23.

[0028] In this embodiment, the third flow path forming member 33 closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, on the side where the exhaust gas outlet 12 is formed. According to the above-mentioned third flow passage forming member 33, the exhaust gas introduced into the gap formed between the inner surface of the casing 10 not blocked by the second flow passage forming member 32 and the outer surface of the wall member 23 and rises while flowing through the gap formed between the inner surface of the casing 10 not blocked by the third flow passage forming member 33 and the outer surface of the wall member 23. The exhaust gas that rises in the flow section formed by the third flow passage forming member 33 is changed in direction by the first flow passage forming member 31 arranged at the upper end of the heat exchange section 20 (wall member 23) and is discharged from the exhaust gas outlet 12 without flowing to the exhaust gas inlet 11 side. That is, the third flow passage forming member 33 blocks a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, thereby forming an exhaust gas flow section 42 that flows the exhaust gas introduced by the exhaust gas introduction section 41 through the gap formed between the inner surface of the casing 10 and the outer surface of the heat exchange section 20 (wall member 23).

[0029] In a cross section perpendicular to the flow direction of exhaust gas flowing inside the heat exchange section 20 (wall member 23), it is preferable that the area of ​​the rectangle formed by the inner surface of the quadrangular prism-shaped heat exchange section 20 (wall member 23) is 40% or more and 60% or less of the area of ​​the circle formed by the inner surface of the cylindrical casing 10.

[0030] Next, the flow of exhaust gas and the flow of water supplied to the water pipe 21 in the heat exchanger 1 of the first embodiment will be described. In the heat exchanger 1 of the first embodiment, exhaust gas is introduced from an exhaust gas inlet 11, passes through a casing 10 and a heat exchange section 20, and is discharged from an exhaust gas outlet 12. Water is supplied from the lower end side of a water tube 21, is heated by the exhaust gas in the heat exchange section 20, becomes steam, and is discharged from the upper end side.

[0031] Exhaust gas introduced from the exhaust gas inlet 11 passes through the inside of the heat exchanger 20 in the shape of a rectangular prism, and reaches the bottom surface of the casing 10 . The exhaust gas that reaches the bottom surface of the casing 10 changes direction and forms an upward flow. The exhaust gas that has formed the upward flow is prevented from ascending by the second flow passage forming member 32, and passes through the exhaust gas introduction part 41 that is disposed in the gap between the casing 10 and the wall member 23.

[0032] The exhaust gas that has passed through the exhaust gas inlet portion 41 passes through the gap between the casing 10 and the wall member 23, is prevented from rising by the third flow passage forming member 33, and passes through the exhaust gas flow portion . The exhaust gas that passes through the exhaust gas flow section 42 passes through the gap between the casing 10 and the wall member 23, and is prevented from rising by the first flow path forming member 31, and a flow toward the exhaust gas outlet 12 is formed, and the exhaust gas is discharged from the exhaust gas outlet 12.

[0033] Due to the above-mentioned flow of exhaust gas, the exhaust gas passing through the gap between the casing 10 and the wall member 23 passes through the gap between the casing 10 and the wall member 23 in a swirling manner without generating any drift toward the exhaust gas outlet 12. The bent portion 212 of the water pipe 21 arranged in the gap between the casing 10 and the wall member 23 is heated by the exhaust gas that passes through the gap between the casing 10 and the wall member 23 in a swirling manner, regardless of the position in the heat exchange section 20 where the bent portion 212 is arranged in the gap between the casing 10 and the wall member 23.

[0034] According to the heat exchanger 1 of the first embodiment described above, the following effects are achieved.

[0035] (1) The heat exchange device 1 includes a heat exchange section 20 through which exhaust gas flows, a casing 10 that houses the heat exchange section 20, and a plurality of flow path forming members 30 that are arranged within the casing 10 and block at least a portion of the gap between the heat exchange section 20 and the casing 10, and the heat exchange section 20 includes a water pipe 21 and a wall member 23. The flow path forming member 30 is configured to include a first flow path forming member 31 that is arranged on one end side of the heat exchange section 20 and blocks the entire gap between the casing 10 and the wall member 23 of the heat exchange section 20; a second flow path forming member 32 that is arranged on the other end side of the heat exchange section 20 and forms an exhaust gas inlet section 41 that introduces exhaust gas between the casing 10 and the wall member 23; and a third flow path forming member 33 that is arranged between the other end side of the heat exchange section 20 and the exhaust gas outlet 12 of the casing 10 and forms an exhaust gas circulation section 42 through which the exhaust gas introduced from the exhaust gas inlet section 41 flows, and the exhaust gas inlet section 41 of the second flow path forming member 32 and the exhaust gas circulation section 42 of the third flow path forming member 33 are arranged at different positions. As a result, by arranging the flow path forming member 30 so that a low-temperature area does not occur on the surface of the water tube 21, which would occur when the exhaust gas flowing in from the upper exhaust gas inlet 11 of the heat exchanger 1 drifts toward the exhaust gas outlet 12, the condensation of exhaust gas containing corrosive components can be suppressed.

[0036] (2) In the heat exchange device 1 of (1) above, the wall member 23 may be cylindrical, the water pipe 21 may have a bent portion 212, and the bent portion 212 of the water pipe 21 may be arranged outside the cylindrical wall member 23. As a result, even if the bent portion 212 of the water pipe 21 is arranged outside the wall member 23 of the heat exchange section 20, by arranging the flow path forming member 30 so that a low-temperature area is not generated on the surface of the bent portion 212 of the water pipe 21, the occurrence of condensation of exhaust gas containing corrosive components can be suppressed.

[0037] (3) In the heat exchange device 1 of (1) or (2) above, the casing 10 may be cylindrical, and the heat exchange section 20 may be rectangular prism-shaped. Thus, by adopting a cylindrical shape for the casing 10 of the heat exchanger 1, it is possible to handle even higher exhaust gas pressure. In addition, by adopting a cylindrical casing 10 and a square prism-shaped heat exchanger 20, a sufficient space can be secured between the casing 10 and the heat exchanger 20.

[0038] (4) In any of the heat exchange devices 1 described above in (1) to (3), in a cross section perpendicular to the exhaust gas flow direction flowing inside the heat exchange section 20 (wall member 23), the area formed by the inner surface of the wall member 23 is 40% or more and 60% or less of the area formed by the inner surface of the casing 10. The exhaust gas flows into the heat exchanger 20 from the exhaust gas inlet 11 and flows inside the wall member 23, whose flow path cross-sectional area is restricted by the straight pipes 211 through which water flows. This reduces the exhaust gas temperature. The exhaust gas with reduced temperature reverses its flow direction at the bottom of the heat exchanger 20, and is changed in flow direction by the second flow path forming member 32 and the third flow path forming member 33. The exhaust gas flows through the exhaust gas flow section 42 while moving in the circumferential direction of the casing 10, and is guided to the exhaust gas outlet 12. By making the area formed by the inner surface of the wall member 23 40% to 60% of the area formed by the inner surface of the casing 10, the heat exchange of the heat exchanger 1 can be effectively performed, and the flow path of the exhaust gas inside the wall member 23 and in the exhaust gas flow section 42 can be secured, thereby suppressing an excessive increase in pressure loss.

[0039] Next, a heat exchanger 1A according to a second embodiment will be described with reference to Figures 6 to 10. Note that Figures 6 and 7 omit the illustration of the water tubes 21 shown in Figure 1.

[0040] FIG. 6 is a diagram showing a heat exchange device 1A according to a second embodiment of the present invention.

[0041] 6, the heat exchange device 1A includes a casing 10, a heat exchange section 20, and a plurality of flow path forming members 30. In this embodiment, the casing 10 and the heat exchange section 20 have the same configuration as those in the first embodiment, so they are denoted by the same reference numerals and the description thereof is omitted.

[0042] The multiple flow path forming members 30 include a first flow path forming member 31, a second flow path forming member 32, a third flow path forming member 33A and a third flow path forming member 33B. In this embodiment, the first flow path forming member 31 in the first embodiment has the same configuration, so it is denoted by the same reference numerals and description thereof will be omitted.

[0043] As shown in FIG. 6 and FIG. 8, the second flow passage forming member 32 is disposed on the lower end side of the heat exchanger 20 (wall member 23) and closes a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. In this embodiment, the second flow passage forming member 32 closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 on the side where the exhaust gas outlet 12 is formed. More specifically, the second flow passage forming member 32 is composed of a plurality of plate-shaped members having arc sides and chord sides and plate-shaped members obtained by dividing the plate-shaped members in half. The arc sides of the second flow passage forming member 32 are joined to the inner circumferential surface of the casing 10 and the chord sides are joined to the wall member 23 by welding, bolts, or the like. As a result, the second flow passage forming member 32 closes a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 by being close to the arc side corresponding to the inner circumferential surface of the casing 10 and the chord side corresponding to the wall member 23.

[0044] In this embodiment, the second flow path forming member 32 closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 on the side where the exhaust gas outlet 12 is formed. According to the above-described second flow passage forming member 32, the exhaust gas introduced into the heat exchange section 20 is introduced downward from the lower end of the heat exchange section 20 (wall member 23), then changes direction at the lower surface of the casing 10, and is introduced into a gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 that is not blocked by the second flow passage forming member 32, and rises. That is, the second flow passage forming member 32 blocks a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, thereby forming an exhaust gas introduction section 41 that introduces the exhaust gas that has passed through the wall member 23 into the gap formed between the inner surface of the casing 10 and the outer surface of the heat exchange section 20 (wall member 23).

[0045] As shown in Figs. 6 and 9, the third flow passage forming member 33A is disposed below the exhaust gas outlet 12 and above the second flow passage forming member 32, and closes a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. In this embodiment, the third flow passage forming member 33A closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 between the exhaust gas outlet 12 and the second flow passage forming member 32. More specifically, the third flow passage forming member 33A is composed of a plurality of plate-shaped members having arc sides and chord sides and plate-shaped members obtained by dividing the plate-shaped members in half, similar to the second flow passage forming member 32. The third flow passage forming member 33A is joined by welding, bolts, or the like, with the arc sides being joined to the inner circumferential surface of the casing 10 and the chord sides being joined to the wall member 23. As a result, the third flow path forming member 33A is adjacent to the arc edge corresponding to the inner surface of the casing 10 and the chord edge corresponding to the wall member 23, thereby blocking a portion of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. In this embodiment, the third flow path forming member 33A closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, on the side where the exhaust gas outlet 12 is formed.

[0046] As shown in Figs. 6 and 10, the third flow passage forming member 33B is disposed below the third flow passage forming member 33A and above the second flow passage forming member 32, and closes a part of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. In this embodiment, the third flow passage forming member 33B closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23 between the exhaust gas outlet 12 and the second flow passage forming member 32. More specifically, the third flow passage forming member 33B is composed of a plurality of plate-shaped members having arc sides and chord sides and plate-shaped members obtained by dividing the plate-shaped members in half, similar to the second flow passage forming member 32 and the third flow passage forming member 33A. The third flow passage forming member 33B is joined by welding, bolts, etc., with the arc sides being joined to the inner circumferential surface of the casing 10 and the chord sides being joined to the wall member 23. As a result, the third flow path forming member 33B is adjacent to the arc edge corresponding to the inner surface of the casing 10 and the chord edge corresponding to the wall member 23, thereby blocking a portion of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23. In this embodiment, the third flow path forming member 33B closes half of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, on the side opposite to the side on which the exhaust gas outlet 12 is formed.

[0047] According to the third flow passage forming member 33A and the third flow passage forming member 33B, the exhaust gas introduced into the gap formed between the inner surface of the casing 10 that is not blocked by the second flow passage forming member 32 and the outer surface of the wall member 23 and rises while flowing through the gap formed between the inner surface of the casing 10 that is not blocked by the third flow passage forming member 33A and the outer surface of the wall member 23. The rising exhaust gas further rises while flowing through the gap formed between the inner surface of the casing 10 that is not blocked by the third flow passage forming member 33A and the outer surface of the wall member 23. The exhaust gas that further rises in the flow section formed by the third flow passage forming member 33A changes direction at the first flow passage forming member 31 arranged at the upper end of the heat exchange section 20 (wall member 23) and is discharged from the exhaust gas outlet 12 without flowing toward the exhaust gas inlet 11 side. That is, the third flow path forming member 33A blocks a portion of the gap formed between the inner surface of the casing 10 and the outer surface of the wall member 23, thereby forming an exhaust gas flow section 42A through which the exhaust gas introduced by the exhaust gas inlet section 41 flows into the gap formed between the inner surface of the casing 10 and the outer surface of the heat exchange section 20 (wall member 23), and the third flow path forming member 33B forms an exhaust gas flow section 42B through which the exhaust gas that has flowed through the exhaust gas flow section 42A flows into the gap formed between the inner surface of the casing 10 and the outer surface of the heat exchange section 20 (wall member 23).

[0048] By arranging multiple flow path forming members 30 as shown in Figures 6 to 10, exhaust gas introduced from the exhaust gas inlet 11 passes through the gap between the casing 10 and the wall member 23 in a swirling manner without generating any drift toward the exhaust gas outlet 12. The bent portion 212 of the water pipe 21 arranged in the gap between the casing 10 and the wall member 23 is heated by the exhaust gas that passes through the gap between the casing 10 and the wall member 23 in a swirling manner, regardless of the position in the heat exchange section 20 where the bent portion 212 is arranged in the gap between the casing 10 and the wall member 23.

[0049] When three or more third flow path forming members 33 are provided, the multiple exhaust gas flow sections 42 are disposed at different positions when viewed in the flow direction of the exhaust gas that has passed inside the heat exchange section 20.

[0050] Next, an exhaust gas boiler system 100 including the above-mentioned heat exchanger 1A will be described with reference to FIG. The exhaust gas boiler system 100 is a system that generates steam by heating water using exhaust gas generated when sludge or the like is burned as a heat source. As shown in FIG. 11, the exhaust gas boiler system 100 of the embodiment includes a plurality (four units) of heat exchangers arranged in series. When the exhaust gas boiler system 100 includes a plurality of heat exchangers arranged in series, the temperature of the exhaust gas introduced into the heat exchanger arranged downstream is lower than the temperature of the exhaust gas introduced into the heat exchanger arranged upstream. Therefore, when exhaust gas containing corrosive components is used in the exhaust gas boiler system 100, the corrosive components may condense in the heat exchanger arranged downstream due to a decrease in the exhaust gas temperature. Therefore, the exhaust gas boiler system 100 of the embodiment uses the heat exchanger 1A of the embodiment as the heat exchanger arranged most downstream among the four heat exchangers, and uses the heat exchanger 101 without the flow path forming member 30 as the three heat exchangers arranged upstream.

[0051] By configuring the exhaust gas boiler system 100 by disposing the heat exchanger 1A of the embodiment at the most downstream position of the exhaust gas boiler system 100, even if the exhaust gas has been cooled due to heat exchange performed upstream of the exhaust gas boiler system, a flow path sufficient for heating the bent portion 212 of the water tube 21 disposed outside the wall member 23 of the heat exchange section 20 can be formed, thereby preventing condensation of the exhaust gas on the surface of the bent portion 212.

[0052] The exhaust gas boiler system 100 described above provides the following advantages.

[0053] (5) The exhaust gas boiler system 100 includes a plurality of heat exchangers 101 and a heat exchanger 1 or a heat exchanger 1A according to any one of (1) to (4) above, which is arranged at the most downstream position of the plurality of heat exchangers 101.

[0054] As a result, in an exhaust gas boiler system 100 including multiple heat exchangers 101, by providing any one of the heat exchangers 1 or heat exchangers 1A described above in (1) to (4) at the most downstream position where the temperature of the exhaust gas is low, condensation occurring on the surface of the bent portion 212 of the water pipe 21 constituting the heat exchanger 1 or heat exchanger 1A can be effectively suppressed.

[0055] Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various changes, modifications, and combinations are possible.

[0056] For example, the second flow passage forming member 32 forms one exhaust gas inlet section 41, but two or more exhaust gas inlet sections 41 may be formed in the second flow passage forming member 32. In addition, the third flow passage forming member 33 forms one exhaust gas circulation section 42, but two or more exhaust gas circulation sections 42 may be formed in the third flow passage forming member 33.

[0057] In the first and second embodiments, the heat exchange devices 1 and 1A including the cylindrical casing 10 have been described, but the present invention is not limited to this. That is, the casing may be configured as a tube having an elliptical cross section, or may be configured as a square tube.

[0058] As the first embodiment, a heat exchanger that heats water to generate steam has been shown, in which the temperature difference of the exhaust gas at the inlet and outlet of the heat exchanger is large (a large amount of heat exchange), and condensation is likely to occur, but the present invention is not limited to this. It may be a heat exchanger that heats water to make it hot water, or circulates steam to superheat it. In addition, the medium to be heated that circulates inside the heat transfer tube may be thermal oil, and the heated thermal oil can be supplied to a dryer or a generator.

[0059] In addition, in the exhaust gas boiler system 100, a system including a plurality of heat exchangers arranged in series has been described, but the present invention is not limited to this. For example, the system may be an incineration facility that includes an incinerator and a heat exchanger 1 and introduces exhaust gas generated in the incinerator into the heat exchanger 1. This makes it possible to effectively prevent condensation from occurring on the surface of the bent portion 212 of the water pipe 21 that constitutes the heat exchange device 1. [Explanation of symbols]

[0060] 1, 1A heat exchange device 10 Casing 11 Exhaust gas inlet 12 Exhaust gas outlet 20 Heat exchange section 21 Water pipe 212 Bend 23 Wall components 30 Flow path forming member 31 First flow passage forming member 32 Second flow path forming member 33 (33A, 33B) third flow path forming member 41 Exhaust gas inlet 42 Exhaust gas flow section 100 Exhaust gas boiler system

Claims

1. a heat exchange section through which exhaust gas flows; A casing that houses the heat exchange unit; a plurality of flow path forming members disposed in the casing and blocking at least a portion of a gap between the heat exchange unit and the casing; The heat exchange unit is A heat transfer tube; a wall member that separates the exhaust gas flowing through the heat exchanger from the exhaust gas flowing inside the casing, The casing comprises: an exhaust gas inlet disposed on one end side of the casing and through which exhaust gas is supplied; an exhaust gas outlet through which exhaust gas flowing through a space formed by the wall member of the heat exchanger and the casing is discharged, The plurality of flow path forming members include a first flow passage forming member that is disposed on one end side of the heat exchange unit, covers an entire gap between the casing and the wall member of the heat exchange unit, and introduces the exhaust gas supplied from the exhaust gas inlet into the wall member of the heat exchange unit; a second flow passage forming member that is disposed on the other end side of the heat exchanger and forms an exhaust gas introduction portion that introduces the exhaust gas that has passed through the wall member of the heat exchanger between the casing and the wall member of the heat exchanger; a third flow path forming member that is disposed between the other end side of the heat exchanger and the exhaust gas outlet of the casing and forms an exhaust gas flow portion through which the exhaust gas introduced from the exhaust gas inlet flows, a heat exchange device in which, when viewed in the flow direction of exhaust gas flowing within the wall member of the heat exchange section, the exhaust gas inlet portion of the second flow path forming member and the exhaust gas flow portion of the third flow path forming member are arranged at different positions.

2. The wall member is cylindrical, The heat transfer tube has a bent portion, The heat exchange device according to claim 1 , wherein the bent portion of the heat transfer tube is disposed outside the cylindrical wall member.

3. The casing is cylindrical in shape, The heat exchange device according to claim 1 , wherein the heat exchange portion has a rectangular prism shape.

4. A heat exchange device as described in any one of claims 1 to 3, wherein in a vertical cross section in the exhaust gas flow direction within the heat exchange section, the area of ​​the vertical cross section formed by the inner surface of the wall member is 40% or more and 60% or less of the area of ​​the vertical cross section formed by the inner surface of the casing.

5. An incinerator, The heat exchange device according to any one of claims 1 to 3, Incineration equipment that introduces exhaust gas generated in the incinerator into the heat exchanger.

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