Boilers and plants

Abstract

To provide a boiler capable of facilitating maintenance of a bed intermediate pipe part.SOLUTION: A boiler includes: a furnace in which a fluidized bed is formed; at least one bed intermediate pipe panel having a bed intermediate pipe part extending in the fluidized bed and a connection pipe part connected to the bed intermediate pipe part, passing through an opening formed on a furnace wall of the furnace and extending on the outer side of the furnace wall; and at least one flange provided on the outer side of the furnace wall to cover the opening and configured to be attachable / detachable to / from the furnace wall.SELECTED DRAWING: Figure 1

Description

【Technical Field】 【0001】 The present disclosure relates to a boiler and a plant. 【Background Art】 【0002】 A boiler may include a furnace in which a fluidized bed is formed. For example, Patent Document 1 describes a boiler in which a heat transfer pipe (in-bed pipe portion) extending inside the fluidized bed is sandwiched between two curved plate members. 【Prior Art Documents】 【Patent Documents】 【0003】 【Patent Document 1】 Japanese Patent Application Laid-Open No. 2000-266311 【Summary of the Invention】 【Problems to be Solved by the Invention】 【0004】 When solid fuel (e.g., biomass fuel, etc.) is introduced into the fluidized bed for combustion, the in-bed pipe portion may be corroded by corrosion components (e.g., chloride components) contained in the solid fuel. Also, when a fluid flows through the inside of the in-bed pipe portion, the in-bed pipe portion may vibrate, shortening the product life of the in-bed pipe portion. Further, wear may occur due to continuous intense collision of the fluidizing material against the outer surface of the in-bed pipe portion. Therefore, the in-bed pipe portion needs to be frequently maintained. However, in the technique described in Patent Document 1, although the vibration of the in-bed pipe portion can be suppressed and the number of times of maintaining the in-bed pipe portion can be reduced, it does not facilitate the maintenance of the in-bed pipe portion. 【0005】 The present disclosure has been made in view of the above problems, and an object thereof is to provide a boiler capable of facilitating the maintenance of the in-bed pipe portion. 【Means for Solving the Problems】 【0006】 To achieve the above objective, the boiler according to the present disclosure comprises: a furnace in which a fluidized bed is formed inside; at least one fluidized bed panel including a fluidized bed section extending inside the fluidized bed and a connecting bed section connected to the fluidized bed section and extending to the outside of the furnace wall through an opening formed in the furnace wall of the furnace; and at least one flange provided on the outside of the furnace wall so as to cover the opening and configured to be detachably attached to the furnace wall. [Effects of the Invention] 【0007】 According to the boiler of this disclosure, maintenance of the mid-layer tube section can be facilitated. [Brief explanation of the drawing] 【0008】 [Figure 1] This diagram schematically shows the configuration of the boiler according to the first embodiment. [Figure 2] This diagram schematically shows the configuration of the furnace wall according to the first embodiment. [Figure 3] This is a diagram illustrating an example of the configuration of the first opening flange according to the first embodiment. [Figure 4] This is a diagram illustrating an example of the configuration of the second opening flange according to the first embodiment. [Figure 5] This diagram schematically shows the configuration of the furnace wall according to the second embodiment. [Figure 6] This is a diagram illustrating the configuration of the other side furnace wall tube according to the second embodiment. [Figure 7] This figure shows the layout of the first flange and the second flange according to several embodiments. [Figure 8] This diagram schematically shows the configuration of a plant according to several embodiments. [Modes for carrying out the invention] 【0009】 Hereinafter, boilers and plants according to embodiments of this disclosure will be described with reference to the drawings. Such embodiments represent one aspect of this disclosure and are not limiting, and can be modified at will within the scope of the technical idea of ​​this disclosure. 【0010】 <First Embodiment> (composition) Figure 1 is a schematic diagram showing the configuration of boiler 1 according to the first embodiment. As illustrated in Figure 1, boiler 1 includes a furnace 2, a mid-layer tube panel 4, and a flange 6. 【0011】 The furnace 2 will now be described. The furnace 2 has a cylindrical shape and a fluidized bed 7 is formed inside. In the configuration illustrated in Figure 1, the furnace 2 has a combustion space 9 formed inside, which is defined by the furnace wall 8, the furnace bottom 10, and the ceiling 12. Solid fuel A1 is supplied to the combustion space 9 through a supply port 14 formed in the furnace wall 8. A supply pipe 16 into which the solid fuel A1 is introduced is connected to the supply port 14. The solid fuel A1 is mixed with the fluidized material A2 supplied to the combustion space 9. Multiple air nozzles 17 are provided in the furnace bottom 10 for supplying combustion air B to the combustion space 9. An extraction pipe 19 for extracting the fluidized material A2 from the fluidized bed 7 is connected to the furnace bottom 10. The configuration for supplying the fluidized material A2 to the furnace 2 is not particularly limited. The furnace 2 is also configured to supply the fluidized material A2 to the combustion space 9 through a fluidized material piping provided separately from the supply pipe 16. 【0012】 The solid fuel A1 is not particularly limited, but in the first embodiment, the solid fuel A1 includes RPF (Refuse derived paper and plastics densified fuel). The fluid material A2 is not particularly limited, but in the first embodiment, the fluid material A2 includes sand. In some embodiments, the solid fuel A1 has a lower density than the fluid material A2. In some embodiments, the solid fuel A1 includes biomass or lignite. In some embodiments, the fluid material A2 includes limestone. 【0013】 The solid fuel A1 and fluidized material A2 supplied to the combustion space 9 are fluidized by the combustion air B blown into the combustion space 9 from below upward, forming a fluidized bed 7 within the combustion space 9. In the fluidized bed 7, the solid fuel A1 and the combustion air B are agitated and mixed, causing the solid fuel A1 to burn. The combustion gas G generated by the combustion of the solid fuel A1 moves to the space above the fluidized bed 7 in the combustion space 9 (freeboard). The combustion gas G is then discharged to the outside of the furnace 2 via a combustion gas line (not shown) connected to the top of the furnace wall 8. The boiler 1 may include a heat exchanger for recovering the heat from the combustion gas G discharged from the furnace 2. 【0014】 In the first embodiment, as illustrated in Figure 1, the boiler 1 further includes a burner 18 provided on the furnace wall 8 of the furnace 2, and burns fuel injected from the burner 18 in the fluidized bed 7. The fuel for the burner 18 may be solid fuel A1, or it may be different from solid fuel A1, for example, gas or heavy oil. Note that the boiler 1 does not necessarily have to be equipped with a burner 18, and may be a boiler 1 of a type in which hot air B is blown into the combustion space 9 from below upward as combustion air, such as a hot blast furnace type, to burn the solid fuel A1. 【0015】 The sub-tube panel 4 will now be described. As illustrated in Figure 1, the sub-tube panel 4 includes a sub-tube section 20 that extends inside the fluidized bed 7, and a connecting pipe section 22 that connects to the sub-tube section 20 and extends outside the furnace wall 8 by passing through an opening 21 formed in the furnace wall 8 of the furnace 2. 【0016】 FIG. 2 is a diagram schematically showing the configuration of the furnace wall 8 according to the first embodiment, and is a view of the opening 21 formed in the furnace wall 8 as viewed from the inside of the furnace 2. As illustrated in FIG. 2, the furnace wall 8 includes a pair of furnace wall tubes 23a and 23b that extend along the vertical direction D1 and are adjacent to each other. The pair of furnace wall tubes 23a and 23b includes a furnace wall forming portion 23c connected to each other via fins 25, and an opening forming portion 23d that forms an opening 21 between the pair of furnace wall tubes 23a and 23b. Each of one furnace wall tube (hereinafter referred to as the one-side furnace wall tube 23a) and the other furnace wall tube (hereinafter referred to as the other-side furnace wall tube 23b) extends linearly along the vertical direction D1. 【0017】 In the first embodiment, a first opening 21A (21) and a second opening 21B (21) are respectively formed in the lower part of the furnace wall 8. The first opening 21A and the second opening 21B face each other in the horizontal direction. Each of the first opening 21A and the second opening 21B is formed in the furnace wall 8 such that a virtual straight line orthogonal to the first opening 21A is also orthogonal to the second opening 21B. Each of the first opening 21A and the second opening 21B faces the fluidized bed 7. 【0018】 The in-bed tube panel 4 is configured such that the fluid C flows from one end 4a to the other end 4b. One end 4a is connected to the inlet tube gathering 24, and the other end 4b is connected to the outlet tube gathering 26. The fluid C flowing in from the inlet tube gathering 24 is water or steam, and exchanges heat with the combustion gas G, solid fuel A1, and fluidizing material A2 in the fluidized bed 7. Then, this fluid C becomes steam or superheated steam and flows out to the outlet tube gathering 26. 【0019】 In the first embodiment, as illustrated in FIG. 1, the connecting pipe portion 22 includes a first opening side connecting pipe portion 22A that extends outside the furnace wall 8 through the first opening 21A, and a second opening side connecting pipe portion 22B that extends outside the furnace wall 8 through the second opening 21B. The first opening side connecting pipe portion 22A includes an inflow portion 27 through which the fluid C flows from the outside of the furnace 2 into the furnace 2, an outflow portion 29 through which the fluid C that has flowed out of the furnace 2 flows, and a first pipe portion 31 through which the fluid C flows out of the furnace 2 and returns to the inside of the furnace 2. The second opening side connecting pipe portion 22B includes a second pipe portion 33 through which the fluid C flows out of the furnace 2 and returns to the inside of the furnace 2. 【0020】 In the inflow portion 27, in the flow direction in which the fluid C flows, one end on the upstream side includes one end 4a of the in-layer pipe panel 4, and the other end on the downstream side is connected to the in-layer pipe portion 20. In the outflow portion 29, in the flow direction, the other end on the downstream side includes the other end 4b of the in-layer pipe panel 4, and one end on the upstream side is connected to the in-layer pipe portion 20. The first pipe portion 31 has a U shape, and both ends are connected to the in-layer pipe portion 20. The second pipe portion 33 has a U shape, and both ends are connected to the in-layer pipe portion 20. 【0021】 In the form illustrated in FIG. 1, two first pipe portions 31 arranged along the vertical direction D1 are provided. That is, an upper first pipe portion 31 and a lower first pipe portion 31 are provided. Also, three second pipe portions 33 arranged along the vertical direction D1 are provided. That is, a lower second pipe portion 33 located at the lowermost position, an upper second pipe portion 33 located at the uppermost position, and an intermediate second pipe portion 33 located between the lower second pipe portion 33 and the upper second pipe portion 33 are provided. 【0022】 In the configuration illustrated in Figure 1, the layered tube section 20 includes the first layered tube 30, the second layered tube 32, the third layered tube 34, the fourth layered tube 36, the fifth layered tube 38, and the sixth layered tube 40. Each of the first to sixth layered tubes 30 extends linearly from the first opening 21A toward the second opening 21B. The first to sixth layered tubes 30 are arranged from bottom to top in the order of first layered tube 30, second layered tube 32, third layered tube 34, fourth layered tube 36, fifth layered tube 38, and sixth layered tube 40. 【0023】 In the flow direction through which the fluid C flows, the first layer pipe 30 has one upstream end connected to the inlet 27 and the other downstream end connected to the lower second pipe section 33. In the flow direction through which the fluid C flows, the second layer pipe 32 has one upstream end connected to the lower second pipe section 33 and the other downstream end connected to the lower first pipe section 31. In the flow direction through which the fluid C flows, the third layer pipe 34 has one upstream end connected to the lower first pipe section 31 and the other downstream end connected to the intermediate second pipe section 33. In the flow direction through which the fluid C flows, the fourth layer pipe 36 has one upstream end connected to the intermediate second pipe section 33 and the other downstream end connected to the upper first pipe section 31. In the flow direction through which the fluid C flows, the fifth layer pipe 38 has one upstream end connected to the upper first pipe section 31 and the other downstream end connected to the upper second pipe section 33. In the flow direction, the sixth layer pipe 40 has one upstream end connected to the upper second pipe section 33 and the other downstream end connected to the outlet section 29. In the first embodiment, the layer pipe panel 4 is configured to reciprocate three times within the fluidized bed 7, but the disclosure is not limited to this configuration. 【0024】 The flange 6 will now be described. The flange 6 is provided on the outside of the furnace wall 8 so as to cover the opening 21 and is configured to be detachable from the furnace wall 8. In the first embodiment, as illustrated in Figure 1, the boiler 1 is provided with a first opening-side flange 6A that covers the first opening 21A and a second opening-side flange 6B that covers the second opening 21B. The first opening-side connecting pipe section 22A is fixed to the first opening-side flange 6A at a penetration section 42 that passes through the first opening-side flange 6A. The first opening-side flange 6A is passed through by the inlet section 27 and the outlet section 29, respectively. 【0025】 The first opening flange 6A and the second opening flange 6B are not particularly limited, as long as they are configured to be detachable from the furnace wall 8. Referring to Figure 3, an example of a configuration in which the first opening flange 6A is detachable from the furnace wall 8 will be described. Figure 3 is a diagram illustrating an example of the configuration of the first opening flange 6A according to the first embodiment. 【0026】 In the first embodiment, the first opening flange 6A is penetrated by both the inlet 27 and the outlet 29. However, since the configurations in which the inlet 27 and the outlet 29 are penetrated are the same, the explanation of the configuration in which the outlet 29 is penetrated is omitted. In some embodiments, the configurations in which the inlet 27 is penetrated and the configurations in which the outlet 29 is penetrated may be different from each other. 【0027】 In the first embodiment, as illustrated in Figure 3, the first opening-side flange 6A includes a sleeve portion 46 that forms a through-hole 44 through which the through-port 42 passes. The sleeve portion 46 extends along the axial direction D2 of the inlet portion 27 of the first opening-side connecting pipe portion 22A. The axial direction D2 of the inlet portion 27 is a direction intersecting the first opening 21A, with one direction of the axial direction D2 being toward the interior of the furnace 2, and the other direction being the opposite direction of the axial direction D2. 【0028】 In the embodiment illustrated in Figure 3, the first opening flange 6A includes a plate-shaped main body portion 48 extending in a direction intersecting the axial direction D2. The main body portion 48 covers the first opening 21A from the other side in the axial direction D2. A hole 51 is formed in the main body portion 48 that penetrates along the axial direction D2. The sleeve portion 46 has a cylindrical shape and extends from the other side 52 of the main body portion 48 in the axial direction D2 so that the hole 51 and the through hole 44 are in communication. When viewed from the axial direction D2, the hole 51 has an opening area through which the through portion 42 can pass, but is configured to be smaller than the opening area of ​​the through hole 44. In other words, when viewed from the axial direction D2, the main body portion 48 includes a protruding portion 54 that protrudes into the through hole 44. The main body portion 48 and the sleeve portion 46 are integrally constructed. 【0029】 In the first embodiment, as illustrated in Figure 3, the inlet portion 27 includes a packing 58 attached to the outer circumferential surface 56 of the through portion 42. When the through portion 42 is passed through the through hole 44, the packing 58 is compressed by the sleeve portion 46, thereby filling the gap 53 between the outer circumferential surface 56 of the through portion 42 and the inner circumferential surface 57 of the sleeve portion 46. At this time, the through portion 42 is fixed to the sleeve portion 46 via the packing 58. In other words, the first opening-side connecting pipe portion 22A is fixed to the first opening-side flange 6A at the through portion 42. 【0030】 In the first embodiment, the packing 58 is a gland packing 59. As illustrated in Figure 3, the boiler 1 further includes a packing retainer 60 that presses the gland packing 59 along one axial direction D2. In the embodiment illustrated in Figure 3, the gland packing 59 is located on the other side of the axial direction D2 from the projection 54. The sleeve portion 46 further includes an extending portion 62 that extends from the tip of the sleeve portion 46 (the other end on the other side of the axial direction D2) in a direction intersecting the axial direction D2, on the opposite side from the through hole 44. The packing retainer 60 includes a contact portion 64 that abuts against the extending portion 62, and a cylindrical pressing portion 66 that extends from the contact portion 64 along one axial direction D2 and is inserted into the gap 53. The extending portion 62 and the contact portion 64 are fastened together, for example, by bolts 65. The gland packing 59 has its contact portion 64 fastened to the extended portion 62 and is pressed by the pressing portion 66, and is sandwiched between the protruding portion 54 and the pressing portion 66. 【0031】 In the first embodiment, as illustrated in Figure 3, the boiler 1 includes a plate 70 attached to the furnace wall 8 and bolts 82 for fastening the first opening flange 6A to the plate 70. The plate 70 has a contact surface portion 78 provided spaced apart from the furnace wall 8. The contact surface portion 78 abuts against the peripheral edge portion 80 of the first opening flange 6A. The peripheral edge portion 80 of the first opening flange 6A is the portion of the main body 48 that is outside the first opening 21A (non-overlapping portion) when the first opening flange 6A is viewed from the axial direction D2. 【0032】 In the embodiment illustrated in Figure 3, the plate 70 further comprises a plate body portion 74 connected to the outer peripheral surface 72 of the furnace wall 8, and a plate extension portion 76 extending from the plate body portion 74 in the other direction in the axial direction D2. The contact surface portion 78 extends from the tip of the plate extension portion 76 (the other end on the other side in the axial direction D2) so as to be spaced apart from the first opening 21A in a direction intersecting the axial direction D2. A bolt 82 fastens the peripheral edge portion 80 of the first opening side flange 6A and the contact surface portion 78 of the plate 70. 【0033】 In the configuration illustrated in Figure 3, a refractory material 86 is cast on the inner surface 84 of the furnace wall 8. The refractory material 86 covers the first opening 21A of the furnace wall 8 from one side in the axial direction D2. The refractory material 86 is, for example, cement. In the configuration illustrated in Figure 3, the first space 88 is formed by being surrounded by the refractory material 86, the plate 70, and the first opening side flange 6A. 【0034】 Next, with reference to Figure 4, an example of a configuration in which the second opening flange 6B is detachable from the furnace wall 8 will be described. Figure 4 is a diagram illustrating an example of the configuration of the second opening flange 6B according to the first embodiment. 【0035】 In the embodiment illustrated in Figure 4, the second opening side flange 6B includes a plate-shaped main body portion 100 that extends along a direction intersecting the axial direction D2. The main body portion 100 covers the second opening 21B from one side in the axial direction D2. 【0036】 In the embodiment illustrated in Figure 4, the boiler 1 comprises a second opening-side plate 102 attached to the furnace wall 8, and a second opening-side bolt 104 for fastening the second opening-side flange 6B to the second opening-side plate 102. The second opening-side plate 102 has a contact surface portion 106 provided spaced apart from the furnace wall 8. The contact surface portion 106 abuts against the peripheral edge portion 108 of the second opening-side flange 6B. The peripheral edge portion 108 of the second opening-side flange 6B is the portion of the main body portion 100 that is outside the second opening 21B (non-overlapping portion) when the second opening-side flange 6B is viewed from the axial direction D2. 【0037】 In the embodiment illustrated in Figure 4, the second opening-side plate 102 further comprises a second opening-side plate main body portion 110 connected to the outer peripheral surface 72 of the furnace wall 8, and a second opening-side plate extension portion 112 extending from the second opening-side plate main body portion 110 in one direction in the axial direction D2. The contact surface portion 106 extends from the tip of the second opening-side plate extension portion 112 (one end on one side in the axial direction D2) so as to be spaced apart from the second opening 21B in a direction intersecting the axial direction D2. The second opening-side bolt 104 fastens the peripheral edge portion 108 of the second opening-side flange 6B and the contact surface portion 106 of the second opening-side plate 102. 【0038】 In the configuration illustrated in Figure 4, the second space 114 is formed by being surrounded by the fire-resistant material 86, the second opening-side plate 102, and the second opening-side flange 6B. The second pipe section 33 is located within the second space 114. The middle pipe section 20 of the second pipe section 33 is supported by the fire-resistant material 86. 【0039】 (Effects / Actions) The operation and effects of the boiler 1 according to the first embodiment will now be described. According to the first embodiment, when maintenance of the mid-layer tube section 20 is required, the refractory material 86 is removed from the furnace wall 8, the inlet section 27 is removed from the inlet header 24, and the outlet section 29 is removed from the outlet header 26. Then, the first opening side flange 6A is removed from the furnace wall 8, and the first opening side connecting pipe section 22A is pulled toward the outside of the furnace 2 (to the other side in the axial direction D2), thereby allowing the mid-layer tube panel 4 to be removed from the furnace 2. This makes maintenance such as replacement and repair of the mid-layer tube section 20 easier. 【0040】 Furthermore, this disclosure is not limited to a configuration in which the entire layer tube panel 4 is removed from the furnace 2. In some embodiments, although not shown, the inlet 27 includes a one-side inlet including a penetration 42 and a other-side inlet located on the other side of the one-side inlet in axial direction D2 and including one end 4a of the layer tube panel 4, and the one-side inlet may be configured to be detachable from the other-side inlet. With such a configuration, the volume of the layer tube panel 4 removed from the furnace 2 can be reduced. 【0041】 According to the first embodiment, as illustrated and explained in Figure 2, by not providing fins 25 between the pair of furnace wall tubes 23a and 23b, an opening 21 through which the connecting tube portion 22 passes can be easily formed. 【0042】 According to the first embodiment, since the first open-side connecting pipe section 22A is fixed to the first open-side flange 6A, the layer tube panel 4 can be removed from the furnace 2 together with the first open-side flange 6A by pulling the first open-side flange 6A or the first open-side connecting pipe section 22A toward the outside of the furnace 2. Also, according to the first embodiment, since the first open-side connecting pipe section 22A includes an inlet section 27 and an outlet section 29, the entire layer tube section 20 can be removed from the furnace 2 by pulling the first open-side flange 6A. 【0043】 In conventional fluidized bed boilers, the corrosive components contained in the RPF cause corrosion of the heat transfer tubes (intermediate tube section) within the fluidized bed, making it difficult to introduce RPF into the fluidized bed. However, according to the boiler 1 of the first embodiment, maintenance such as replacement and repair of the intermediate tube section 20 is made easier, allowing the boiler 1 to be quickly brought into operational condition. Therefore, RPF can be introduced into the fluidized bed 7 and burned, and the energy generated by the combustion of the RPF can be recovered. 【0044】 According to the first embodiment, since the gland packing 59 is attached to the outer circumferential surface 56 of the penetration portion 42, the airtightness of the first space 88 can be improved so that the fluid material A2 does not leak out of the furnace 2 while firmly fixing the first opening side flange 6A to the first opening side connecting pipe portion 22A. In the first embodiment, the packing 58 was a gland packing 59, but the present disclosure is not limited to this form. The packing 58 may be, for example, an O-ring. 【0045】 In the first embodiment, a gland packing 59 was provided between the outer circumferential surface 56 of the through-hole 42 and the inner circumferential surface 57 of the sleeve portion 46 in order to ensure airtightness of the first space 88 while fixing the first opening-side flange 6A to the first opening-side connecting pipe portion 22A. However, this disclosure is not limited to this embodiment. In some embodiments, the sleeve portion 46 may have a through-hole 44 formed such that the inner circumferential surface 57 of the sleeve portion 46 abuts against the outer circumferential surface 56 of the through-hole 42. 【0046】 According to the first embodiment, the presence of the plate 70 allows the first opening-side flange 6A to be attached to the furnace wall 8 without interfering with the furnace wall 8. 【0047】 In the first embodiment, a second opening 21B was formed in the furnace wall 8, and the second pipe section 33 passed through the second opening 21B, but this disclosure is not limited to this form. In some embodiments, although not shown, a second opening 21B is not formed in the furnace wall 8, and in the flow direction of the fluid C, the other downstream end of the first layer pipe 30 and the upstream end of the second layer pipe 32 are located within the fluidized bed 7. The layer pipe section 20 includes a connecting pipe that connects the other downstream end of the first layer pipe 30 and the upstream end of the second layer pipe 32. In this case, the boiler 1 includes only the first opening side flange 6A and does not include the second opening side flange 6B. 【0048】 <Second Embodiment> A boiler 1 according to a second embodiment of this disclosure will now be described. The boiler 1 according to the second embodiment differs from the first embodiment in that the mid-layer tube panel 4 further comprises a fixed portion 134. In the second embodiment, components that are the same as those of the first embodiment are denoted by the same reference numerals, and their detailed description is omitted. 【0049】 (composition) Figure 5 is a schematic diagram showing the configuration of the furnace wall 8 according to the second embodiment, and is a view of the first opening 21A from inside the furnace 2. The first opening 21A is formed in the opening-forming portion 23d of a pair of furnace wall tubes 23a and 23b. In the embodiment illustrated in Figure 5, one side furnace wall tube 23a extends linearly along the vertical direction D1, while the other side furnace wall tube 23b includes a portion that protrudes on the opposite side from the one side furnace wall tube 23a. Specifically, the other side furnace wall tube 23b includes a lower furnace wall tube section 124, an upper furnace wall tube section 126 located above the lower furnace wall tube section 124, a first enlarged section 128 where the length d1 between the pair of furnace wall tubes 23a and 23b increases as it extends upward from the upper end 125 of the lower furnace wall tube section 124, a second enlarged section 130 where the length d1 increases as it extends downward from the lower end 127 of the upper furnace wall tube section 126, and a connecting section 132 connecting the first enlarged section 128 and the second enlarged section 130. The other side furnace wall tube 23b includes, in order from bottom to top, the lower furnace wall tube section 124, the first enlarged section 128, the connecting section 132, the second enlarged section 130, and the upper furnace wall tube section 126. The opening forming section 23d is located between the one side furnace wall tube 23a and the connecting section 132. 【0050】 Each of the lower furnace wall tube section 124, the upper furnace wall tube section 126, and the connecting section 132 extends along the vertical direction D1 such that its length d1 is constant. In other words, each of the lower furnace wall tube section 124, the upper furnace wall tube section 126, and the connecting section 132 extends along the vertical direction D1 such that they are parallel to each other with respect to the one-side furnace wall tube 23a. The length between the connecting section 132 and the one-side furnace wall tube 23a is greater than the length between the lower furnace wall tube section 124 and the one-side furnace wall tube 23a, and the length between the upper furnace wall tube section 126 and the one-side furnace wall tube 23a, respectively. 【0051】 Figure 6 is a diagram illustrating the configuration of the other side furnace wall tube 23b according to the second embodiment. As illustrated in Figure 6, the lower furnace wall tube section 124 and the upper furnace wall tube section 126 are arranged such that their positions in the axial direction D2 overlap with those of the one side furnace wall tube 23a. The first enlargement 128 extends upward from the upper end 125 of the lower furnace wall tube section 124 toward the other side in the axial direction D2. The second enlargement 130 extends downward from the lower end 127 of the upper furnace wall tube section 126 toward the other side in the axial direction D2. The connecting section 132 is offset to the other side in the axial direction D2 compared to the one side furnace wall tube 23a. 【0052】 In the second embodiment, as illustrated in Figures 5 and 6, the layered tube panel 4 includes a fixing portion 134 that is secured by fins 25. In the embodiment illustrated in Figures 5 and 6, the fixing portion 134 is provided below the inlet portion 27, which is the lowest part of the first opening-side connecting tube portion 22A. A recess 136 (see Figure 6) that is recessed upward is formed on the lower surface of the fixing portion 134. The fins 25 are inserted into the recess 136. 【0053】 (Effects / Actions) The operation and effects of the boiler 1 according to the second embodiment will now be described. As the temperature of the fluidized bed 7 rises, thermal expansion occurs in the sub-tube panel 4, and there is a risk that the refractory material and the sub-tube panel 4 may be damaged by the stress caused by this thermal expansion. According to the second embodiment, the fixed part 134 located near the boundary between the inlet section 27 and the first sub-tube 30 of the sub-tube panel 4 can be used as the starting point for thermal expansion. Therefore, the impact on the refractory material and the sub-tube panel 4 can be minimized, and damage can be suppressed. This disclosure does not limit the installation location of the fixed part 134, and the fixed part 134 may be provided in the first pipe section 31, the outlet section 29, or the second pipe section 33. 【0054】 When the first opening-side connecting pipe section 22A is large in diameter, if the one-side furnace wall pipe 23a and the other-side furnace wall pipe 23b each extend linearly along the vertical direction D1, it may be difficult to secure a first opening 21A through which the first opening-side connecting pipe section 22A can pass. According to the second embodiment, as illustrated and explained in Figure 5, the first opening 21A is formed between the one-side furnace wall pipe 23a and the connecting section 132 (the portion of the other-side furnace wall pipe 23b that protrudes on the side opposite to the one-side furnace wall pipe 23a). Therefore, even if the first opening-side connecting pipe section 22A is large in diameter, it is possible to secure a first opening 21A through which the first opening-side connecting pipe section 22A can pass. Furthermore, according to the second embodiment, as illustrated and explained in Figure 6, the connecting section 132 is offset to the other side in the axial direction D2 compared to the one-side furnace wall pipe 23a. Therefore, it becomes easier to increase the diameter of the first opening 21A. 【0055】 Figure 7 shows the layout of the first flange 6C and the second flange 6D according to several embodiments. In Figure 7, the furnace wall 8 is viewed from the outside of the furnace 2 (the other side in the axial direction D2). In some embodiments, the boiler 1 is provided with a first layer tube panel 4A(4), a second layer tube panel 4B(4) separate from the first layer tube panel 4A, a first flange 6C(6), and a second flange 6D(6) separate from the first flange 6C. As illustrated in Figure 7, the first layer tube panel 4A is fixed to the first flange 6C by gland packing 59. The second layer tube panel 4B is fixed to the second flange 6D by gland packing 59. The first flange 6C and the second flange 6D are configured to be detachably attached to the furnace wall 8 independently of each other. The first flange 6C is provided on the outside of the furnace wall 8 detachably from the furnace wall 8 via a first bolt 82A(82). The second flange 6D is detachably attached to the furnace wall 8 via a second bolt 82B (82), which is separate from the first bolt 82A, and is located on the outside of the furnace wall 8. The first flange 6C and the second flange 6D are spaced apart from each other along the width direction of the furnace wall 8 (directions perpendicular to the vertical direction D1 and the axial direction D2). 【0056】 According to the configuration illustrated in Figure 7, if maintenance is required on the tube section 20 of the first layer tube panel 4A, only the first layer tube panel 4A can be removed from the furnace 2. Similarly, if maintenance is required on the tube section 20 of the second layer tube panel 4B, only the second layer tube panel 4B can be removed from the furnace 2. Therefore, the first layer tube panel 4A and the second layer tube panel 4B can each be maintained individually. 【0057】 Figure 8 is a schematic diagram showing the configuration of a plant 200 according to several embodiments. As illustrated in Figure 8, the plant 200 is equipped with a boiler 1, and with the first opening flange 6A removed from the furnace wall 8, a withdrawal space 140 is formed that allows the mid-layer tube panel 4 to be withdrawn from the furnace 2. 【0058】 The withdrawal space 140 includes a region extending from the first opening 21A to the other side in the axial direction D2. If L1 is the length from one end to the other of the layer tube panel 4 in the axial direction D2, and L2 is the length of the withdrawal space 140 in the axial direction D2, then L2 > L1. The withdrawal space 140 may be formed outdoors, such as in a parking lot, or indoors, such as inside a building. In the embodiment illustrated in Figure 8, the furnace 2 is located on the ground 150, and the flange 6 is attached to the lower part of the furnace wall 8 close to the ground 150. 【0059】 According to the configuration illustrated in Figure 8, the layer tube panel 4 can be removed from the furnace 2 without cutting or bending it. With the configuration illustrated in Figure 8, since the flange 6 is attached to the lower part of the furnace wall 8, the amount of work at height can be reduced. 【0060】 The contents described in each of the above embodiments can be understood, for example, as follows: 【0061】 [1] The boiler (1) relating to this disclosure is A furnace (2) in which a fluidized bed (7) is formed inside, A fluidized bed includes at least one fluidized bed panel (4) comprising a fluidized bed section (20) extending within the fluidized bed and a connecting section (22) connected to the fluidized bed section and extending to the outside of the furnace wall through an opening (21) formed in the furnace wall (8) of the furnace, The system includes at least one flange (6) provided on the outside of the furnace wall so as to cover the opening and configured to be detachable from the furnace wall. 【0062】 According to the configuration described in [1] above, when maintenance of the sub-layer tube section is required, the flange can be removed from the furnace wall and the connecting pipe section can be pulled outwards from the furnace, thereby removing the sub-layer tube panel, including the connecting pipe section and the sub-layer tube section. This makes maintenance such as replacement and repair of the sub-layer tube section easier. 【0063】 [2] In some embodiments, in the configuration described in [1] above, The connecting pipe portion is fixed to the at least one flange at a through-port (42) that penetrates the at least one flange. 【0064】 According to the configuration described in [2] above, the flange or connecting pipe section can be pulled outwards from the furnace, thereby removing the flange along with the connecting pipe section and the layered pipe section, as well as the layered pipe panel, from the furnace. 【0065】 [3] In some embodiments, in the configuration described in [2] above, The at least one flange includes a sleeve portion (46) that forms a through hole (44) through which the through portion passes, and which extends along the axial direction (D2) of the connecting pipe portion. 【0066】 According to the configuration described in [3] above, the penetration portion of the connecting pipe passes through the penetration hole of the sleeve portion, thereby fixing the flange to the connecting pipe while improving the airtightness of the surrounding space of the portion of the connecting pipe closer to the furnace wall than the penetration portion. 【0067】 [4] In some embodiments, in the configuration described in [3] above, The through portion is fixed to the sleeve portion via a packing (58) attached to the outer circumferential surface (56) of the through portion. 【0068】 According to the configuration described in [4] above, compared to the configuration described in [3] above, the flange can be firmly fixed by the connecting pipe, while improving the airtightness of the space around the portion of the connecting pipe that is on the furnace wall side of the penetration. 【0069】 [5] In some embodiments, in the configuration described in [4] above, The aforementioned packing is a gland packing (59), The system further includes a packing retainer (60) that presses the gland packing along the axial direction of the connecting pipe. 【0070】 According to the configuration described in [5] above, by adjusting the magnitude of the force with which the packing retainer presses against the gland packing, it is possible to easily achieve both fixing the flange to the connecting pipe and ensuring airtightness of the surrounding space of the portion of the connecting pipe that is on the furnace wall side of the penetration. 【0071】 [6] In some embodiments, in the configuration described in any one of [1] to [5] above, A plate attached to the furnace wall, comprising a plate (70) spaced apart from the furnace wall and having a contact surface portion (78) that abuts against the peripheral edge portion (80) of at least one flange, The system further comprises a bolt (82) for fastening the peripheral edge of at least one flange to the contact surface of the plate. 【0072】 According to the configuration described in [6] above, the presence of the plate allows the flange to be attached to the furnace wall without interfering with the furnace wall. 【0073】 [7] In some embodiments, in the configuration described in any one of [1] to [6] above, The furnace wall includes a pair of adjacent furnace wall tubes (23a, 23b) that extend along the vertical direction (D1). The pair of furnace wall tubes include a furnace wall forming portion (23c) connected to each other via fins (25), and an opening forming portion (23d) that forms the opening between the pair of furnace wall tubes. 【0074】 According to the configuration described in [7] above, by not providing fins between the pair of furnace wall tubes, an opening through which the connecting tube passes can be easily formed. 【0075】 [8] In some embodiments, in the configuration described in [7] above, The at least one layered tube panel includes a fixing portion (134) that is secured by the fins. 【0076】 In the sub-tube panel, thermal expansion occurs as the temperature of the fluidized bed rises, and the stress caused by this thermal expansion may damage the sub-tube panel. According to the configuration described in [8] above, the fixed portion of the sub-tube panel can be used as the starting point for thermal expansion. Therefore, damage to the sub-tube panel can be suppressed. 【0077】 [9] In some embodiments, in the configuration described in any one of [1] to [8] above, The connecting pipe section includes an inlet (27) through which the fluid (C) flows toward the inside of the furnace, and an outlet (29) through which the fluid that has flowed out from the inside of the furnace flows. 【0078】 According to the configuration described in [9] above, the layer tube section can be removed from the furnace by pulling the flange toward the outside of the furnace. 【0079】

[10] In some embodiments, in the configuration described in any one of [1] to [9] above, The at least one layered tube panel includes a first layered tube panel (4A) and a second layered tube panel (4B) separate from the first layered tube panel. The at least one flange includes a first flange (6C) and a second flange (6D) separate from the first flange, The first layer tube panel is fixed to the first flange, The second layer middle tube panel is fixed to the second flange, The first flange and the second flange are configured to be detachably attached to the furnace wall independently of each other. 【0080】 According to the configuration described in

[10] above, when maintenance of the tube section of the first layer tube panel is required, the first layer tube panel can be removed from the furnace by pulling the connecting tube section of the first layer tube panel toward the outside of the furnace. Similarly, when maintenance of the tube section of the second layer tube panel is required, the second layer tube panel can be removed from the furnace by pulling the connecting tube section of the second layer tube panel toward the outside of the furnace. Therefore, the first layer tube panel and the second layer tube panel can be maintained individually. 【0081】

[11] In some embodiments, in the configuration described in any one of [1] to

[10] above, The fluidized bed is configured to accept RPF (Refuse Derived Fuel). 【0082】 The configuration described in

[11] above can be applied to boilers in which RPF is fed into the fluidized bed. In particular, because it contains a certain amount of chloride components that corrode the sub-bed tubes, it becomes possible to utilize a large amount of RPF that was previously incinerated and could not be utilized (heat recovered) as fuel. 【0083】

[12] Plants according to several embodiments include The boiler is provided as described in any one of the above [1] to

[11] , With at least one flange removed from the furnace wall, a withdrawal space (140) is formed that allows the at least one layer tube panel to be withdrawn from the furnace. 【0084】 According to the configuration described in

[12] , the layer tube panels can be removed from the furnace without cutting or bending them. [Explanation of symbols] 【0085】 1 Boiler 2 Furnace 4-layer tube panel 4A First layer central tube panel 4B Second layer central tube panel 6 flanges 6A First opening side flange 6B Second opening side flange 6C First Flange 6D Second Flange 7 Fluidized bed 8 Furnace wall 20 layer middle pipe section 21 Aperture 21A 1st opening 21B 2nd opening 22 Connecting pipe section 22A First opening side connecting pipe section 22B Second opening side connecting pipe section 23a One-sided furnace wall tube 23b Other side furnace wall tube 23c Furnace wall forming part 23d Aperture forming part 25 fins 27 Inlet 29 Outlet 42 Penetration 44 Through holes 46 Sleeve section 56 Outer surface of the through-hole 58 Packing 59 Gland Packing 60 Packing retainer 70 plates 78 Contact surface part 80 Peripheral area 82 volts 82A First bolt 82B Second bolt 134 Fixed part 140 pull-out space 200 プラント A1 Solid fuels A2 Flowing Material C fluid D1 Up and down directions D2 axis direction

Claims

[Claim 1] A furnace in which a fluidized bed is formed inside, A layered tube panel comprising a layered tube section extending inside the fluidized bed, and a connecting tube section connected to the layered tube section and extending outside the furnace wall through an opening formed in the furnace wall of the furnace, It comprises at least one flange provided on the outside of the furnace wall so as to cover the opening and configured to be detachably attached to the furnace wall, A plate attached to the furnace wall, the plate being spaced apart from the furnace wall and having a contact surface portion that abuts against the peripheral edge of at least one flange, The system further comprises a bolt for fastening the peripheral edge of at least one flange to the contact surface of the plate. Boiler. [Claim 2] A furnace in which a fluidized bed is formed inside, A layered tube panel comprising a layered tube section extending inside the fluidized bed, and a connecting tube section connected to the layered tube section and extending outside the furnace wall through an opening formed in the furnace wall of the furnace, A refractory material provided on the inside of the furnace wall and closing the opening, It comprises at least one flange provided on the outside of the furnace wall so as to cover the opening and configured to be detachably attached to the furnace wall, The at least one flange includes a plate-shaped main body portion that is positioned between it and the fire-resistant material with a first space in between, The at least one layered tube panel includes a first tube section arranged in the first space, through which a fluid flowing inside the layered tube panel flows out from inside the furnace and returns to inside the furnace. Boiler. [Claim 3] The connecting pipe portion is fixed to the at least one flange at a penetration portion that goes through the at least one flange. The boiler according to claim 1 or 2. [Claim 4] The at least one flange includes a sleeve portion that forms a through hole through which the through portion passes, and includes a sleeve portion that extends along the axial direction of the connecting pipe portion. The boiler according to claim 3. [Claim 5] The through portion is fixed to the sleeve portion via a packing attached to the outer circumferential surface of the through portion. The boiler according to claim 4. [Claim 6] The aforementioned packing is a gland packing, The gland packing is further provided with a packing retainer that presses the gland packing along the axial direction of the connecting pipe section. The boiler according to claim 5. [Claim 7] The furnace wall includes a pair of furnace wall tubes that extend vertically and are adjacent to each other. The pair of furnace wall tubes includes a furnace wall forming portion connected to each other via fins, and an opening forming portion that forms the opening between the pair of furnace wall tubes. A boiler according to any one of claims 1 to 6. [Claim 8] The at least one layered tube panel includes a fixing portion that is secured by the fins, The boiler according to claim 7. [Claim 9] The connecting pipe section includes an inlet through which the fluid flows toward the interior of the furnace, and an outlet through which the fluid that has flowed out from the interior of the furnace flows. A boiler according to any one of claims 1 to 8. [Claim 10] The at least one layered tube panel includes a first layered tube panel and a second layered tube panel separate from the first layered tube panel. The at least one flange includes a first flange and a second flange separate from the first flange, The first layer tube panel is fixed to the first flange, The second layer middle tube panel is fixed to the second flange, The first flange and the second flange are configured to be detachably attached to the furnace wall independently of each other. A boiler according to any one of claims 1 to 9. [Claim 11] The fluidized bed is configured to receive RPF. A boiler according to any one of claims 1 to 10. [Claim 12] A boiler according to any one of claims 1 to 11, With at least one flange removed from the furnace wall, a withdrawal space is formed that allows at least one layer tube panel to be withdrawn from the furnace. plant.

Images