JPWO2014141828A1 - Gas nozzle mounting structure - Google Patents

Abstract

A gas pipe (23) embedded in the bottom of the furnace (3) having the combustion chamber (4) and extending upward toward the combustion chamber (4) and connected to the upper end side of the gas pipe (23), combustion of the furnace The gas nozzle mounting structure in which the gas nozzle (25) protruding into the room and the connecting portion (31) between the gas pipe (23) and the gas nozzle (25) are arranged in the bottom (29, 3e).

Description

  The present invention relates to a gas nozzle mounting structure.

  Conventionally, as a circulating fluidized bed boiler, what is shown in patent documents 1 is known. This circulating fluidized bed boiler includes a furnace having a combustion chamber. The combustion chamber fluidizes and combusts the combustion product and the fluid medium. In addition, an air diffuser provided with a wind box and a gas nozzle and a discharge device for discharging ash are provided at the bottom of the furnace. The gas nozzle blows combustion gas into the combustion chamber through the wind box. The fluid ejected from the gas nozzle through the pipe causes the fluid medium in the combustion chamber to flow, thereby forming a fluidized bed.

JP 2012-220099 A

  By the way, during operation of such a circulating fluidized bed boiler, the gas nozzle is exposed to a fluid medium that flows vigorously. For this reason, deterioration of the gas nozzle due to wear is unavoidable, and it is necessary to replace the gas nozzle periodically. Therefore, it is required that the conventional gas nozzle has a structure that can be easily replaced. On the other hand, the gas nozzle may fall off the pipe due to wear, and the dropped gas nozzle may be discharged from the ash outlet and may be bitten by a conveyor or the like to cause a trip. Accordingly, there is a need for a gas nozzle that does not easily fall off and can be easily replaced.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a gas nozzle mounting structure that can prevent dropout and can be easily replaced.

  A gas nozzle mounting structure according to an embodiment of the present invention is embedded in a bottom portion of a furnace having a combustion chamber, is connected to a gas pipe extending upward toward the combustion chamber, and an upper end side of the gas pipe, and is installed in the combustion chamber of the furnace. A protruding gas nozzle, and a connecting portion between the gas pipe and the gas nozzle is disposed in the bottom.

  According to this gas nozzle mounting structure, the connecting portion between the gas pipe buried in the bottom portion of the furnace and the gas nozzle protruding into the combustion chamber of the furnace is arranged in the bottom portion. Therefore, it is possible to prevent the gas nozzle from coming off at the connecting portion. Therefore, it is possible to prevent the gas nozzle from dropping from the gas pipe. Moreover, a gas nozzle can be removed by canceling | releasing the connection in a connection part. As described above, the gas nozzle can be prevented from falling off, and the gas nozzle can be easily replaced.

  Moreover, the attachment structure of the gas nozzle includes a fixing portion that fixes the gas nozzle so as not to move with respect to the furnace, and the fixing portion may not be exposed in the combustion chamber. According to such a gas nozzle mounting structure, since the fixing portion that immovably fixes the gas nozzle to the furnace is not exposed to the combustion chamber, the fixing portion can be prevented from being worn. Therefore, since the state where the gas nozzle is fixed so as to be immovable with respect to the furnace can be maintained, it is possible to prevent the gas nozzle from dropping from the gas pipe. In addition, the gas nozzle can be removed by an easy operation of simply removing the fixing portion. As described above, the gas nozzle can be prevented from falling off, and the gas nozzle can be easily replaced.

  The gas nozzle mounting structure further includes a pin extending in the vertical direction inside the gas pipe, the upper end side of the pin is fixed to the gas nozzle, and the lower end side of the pin is fixed to the lower end side of the gas pipe. May include a first fixing portion for fixing the upper end side of the pin and the gas nozzle. According to such a gas nozzle mounting structure, the gas nozzle is supported by being fixed to the upper end side of the pin and the lower end side of the pin being fixed to the lower end side of the gas pipe. Since the 1st fixing | fixed part which fixes the upper end side of a pin and a gas nozzle is not exposed to a combustion chamber, it can prevent that the said 1st fixing | fixed part wears. Therefore, since the state where the gas nozzle is supported by the pin can be maintained, it is possible to prevent the gas nozzle from dropping from the gas pipe. In addition, since the upper end side of the pin is fixed to the gas nozzle and the lower end side of the pin is fixed to the lower end side of the gas pipe, it is easy to remove the pin on the lower end side of the gas pipe. The gas nozzle can be removed together with the pin. As described above, the gas nozzle can be prevented from falling off, and the gas nozzle can be easily replaced.

  Moreover, a fixing | fixed part is provided with the 2nd fixing | fixed part which fixes the lower end side of a pin, and the 2nd fixing | fixed part may be arrange | positioned on the outer side of gas piping. According to such a gas nozzle mounting structure, the gas nozzle can be easily attached and detached as compared to the case where the second fixing portion is disposed inside the gas pipe.

  Moreover, the 1st fixing | fixed part may be formed by joining the inner wall face of a gas nozzle, and the upper end side of a pin. According to such a gas nozzle mounting structure, the first fixing portion that is not exposed to the combustion chamber can be easily formed.

  Moreover, the 2nd fixing | fixed part may fix the lower end side of a pin to the support part arrange | positioned in the area | region below the lower end part of gas piping. According to such a gas nozzle mounting structure, the formation and removal of the second fixing portion is facilitated.

  According to the present invention, it is possible to provide a gas nozzle mounting structure that can prevent dropout and can be easily replaced.

It is a figure which shows the structure of the circulating fluidized bed boiler to which the attachment structure of the gas nozzle which concerns on embodiment of this invention is applied. It is a schematic sectional drawing which shows the bottom part of the furnace in the circulating fluidized bed boiler of FIG. It is the schematic sectional drawing which looked at FIG. 2 from the top. It is a schematic sectional drawing of the attachment structure of the gas nozzle which concerns on embodiment of this invention, Comprising: It is an expanded sectional view of the gas nozzle shown in FIG. It is sectional drawing along the VV line shown in FIG. It is a schematic sectional drawing of the attachment structure of the gas nozzle which concerns on other embodiment, Comprising: It is a figure corresponding to FIG. It is an expanded sectional view of the fixing | fixed part of gas piping and a pin shown in FIG.

  Hereinafter, embodiments of a gas nozzle mounting structure according to the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

  With reference to FIG. 1, first, the configuration of a circulating fluidized bed boiler to which the gas nozzle mounting structure of the present embodiment is applied will be described. FIG. 1 is a diagram showing a configuration of a circulating fluidized bed boiler to which a gas nozzle mounting structure according to an embodiment of the present invention is applied. As shown in FIG. 1, the circulating fluidized bed boiler 2 includes a fluidized bed furnace 3 having a vertically long cylindrical shape. A fuel inlet 3a for introducing fuel is provided in the middle part of the furnace 3, and a gas outlet 3b for discharging combustion gas is provided at the upper part. The fuel supplied to the furnace 3 from the fuel input device 5 is input into the furnace 3 through the fuel input port 3a.

  A cyclone 7 that functions as a solid-gas separator is connected to the gas outlet 3 b of the furnace 3. The discharge port 7a of the cyclone 7 is connected to a downstream gas processing system via a gas line. A return line 9 called a downcomer extends downward from the bottom outlet of the cyclone 7, and the lower end of the return line 9 is connected to the intermediate side surface of the furnace 3.

  The furnace 3 has a combustion chamber 4 therein. In the combustion chamber 4, a solid material containing fuel introduced from the fuel input port 3 a flows due to combustion / flowing gas (for example, air) introduced from the bottom of the furnace 3 described later, and the fuel flows while flowing. Burn at about 800-900 ° C. The combustion gas generated in the combustion chamber 4 is introduced into the cyclone 7 with accompanying solid particles. The cyclone 7 separates the solid particles and the gas by a centrifugal separation action, returns the separated solid particles to the combustion chamber 4 through the return line 9, and also discharges the combustion gas from which the solid particles have been removed from the discharge port 7a. It is sent to the gas processing system at the subsequent stage through the line. Solid particles are reused.

  In this combustion chamber 4, combustion ash is generated and collected at the bottom. For this reason, in the furnace 3, combustion ash is regularly discharged | emitted from the discharge port 3d of the bottom part outside.

  The gas treatment system includes a gas heat exchange device 13 connected to the discharge port 7a of the cyclone 7 via a gas line, and a bag filter connected to the discharge port 13a of the gas heat exchange device 13 via a gas line. (Dust collector) 15. The gas heat exchanger 13 is provided with a boiler tube 13b that allows water to flow across the exhaust gas flow path. When the high-temperature exhaust gas sent from the cyclone 7 comes into contact with the boiler tube 13b, the heat of the exhaust gas is recovered in the water in the tube, and the generated high-temperature steam is sent to the turbine for power generation through the boiler tube 13b. The bag filter 15 removes fine particles such as fly ash still entrained in the combustible gas. The clean gas discharged from the discharge port 15a of the bag filter 15 is discharged from the chimney 19 via the gas line and the pump 17 to the outside.

  Next, the bottom of the furnace of the circulating fluidized bed boiler to which the gas nozzle mounting structure according to this embodiment is applied will be described in detail with reference to FIGS. 2 and 3. 2 is a schematic cross-sectional view showing the bottom of the furnace in the circulating fluidized bed boiler of FIG. 1, and FIG. 3 is a schematic cross-sectional view of FIG. 2 as viewed from above. As shown in FIG. 2, a wind box 21 is provided below the bottom 3 e of the furnace 3. In addition, a plurality of gas pipes 23 are erected on the upper side of the bottom portion 3 e and extend toward the combustion chamber 4. A plurality of gas nozzles 25 are connected to the respective upper ends of the plurality of gas pipes 23. The wind box 21 is provided with a supply path 27 for introducing combustion / flowing gas. The combustion / flowing gas introduced from the supply passage 27 is sent to the entire combustion chamber 4 through the wind box 21, the gas pipe 23 and the gas nozzle 25 so as to be uniform.

  A refractory material 29 is formed above the bottom 3 e of the furnace 3, and a plurality of discharge ports 3 d for discharging the combustion ash are provided between the refractory materials 29. The gas pipe 23 is erected on the bottom 3 e of the furnace 3 and extends upward through the refractory material 29. The periphery of the gas pipe 23 is covered with a refractory material 29. The gas nozzle 25 connected to the upper end of the gas pipe 23 is exposed partly or entirely without being covered with the refractory material 29, and protrudes toward the combustion chamber 4. The gas nozzle 25 is arranged such that the jet port for sending the gas into the combustion chamber 4 is directed toward the discharge port 3d. During operation of the furnace 3, the gas sent from the gas nozzle 25 flows in the direction indicated by the arrow. The direction indicated by the arrow is referred to as “ejection direction D1”, which is the direction in which the gas nozzle 25 ejects gas. In the present embodiment, the ejection direction D1 is set in a direction orthogonal to the axis of the gas pipe 23, but may be set in an inclined direction.

  As shown in FIG. 3, a plurality of (for example, several thousand) gas nozzles 25 are arranged side by side at the bottom 3 e of the furnace 3. During operation of the furnace 3, the gas ejected from the ejection ports of the respective gas nozzles 25 flows in the ejection direction D1 toward the discharge port 3d.

  Next, the gas nozzle mounting structure according to the present embodiment will be described in detail with reference to FIGS. 4 and 5. 4 is a schematic cross-sectional view of the gas nozzle mounting structure according to the embodiment of the present invention, and is an enlarged cross-sectional view of the gas nozzle shown in FIG. 2, and FIG. 5 is a cross-sectional view taken along line VV shown in FIG. It is. As shown in FIGS. 4 and 5, the gas nozzle mounting structure 1 according to the present embodiment is embedded in the bottom portion of the furnace 3 having the combustion chamber 4 and extends upward toward the combustion chamber 4. A gas nozzle 25 connected to the upper end side of the gas pipe 23 and protruding into the combustion chamber 4 of the furnace 3, and a connecting portion (here, a pipe joint portion 31) between the gas pipe 23 and the gas nozzle 25 is a bottom portion. Is placed inside. Here, the “bottom part” (that is, “bottom part” in the claims) refers to a structure on the bottom side of the furnace 3, and includes not only the bottom part 3e as a wall surface on the bottom side but also a refractory on the bottom part 3e. Also includes material 29. The connecting portion is a portion where the connection is released when the gas nozzle 25 is replaced. In the present embodiment, the connecting portion (that is, the pipe joint portion 31) is disposed in the refractory material 29 in the bottom portion of the furnace 3. Further, the gas nozzle mounting structure 1 includes a fixing portion that fixes the gas nozzle 25 so as not to move with respect to the furnace 3, and the fixing portion is not exposed in the combustion chamber 4. The fixing unit includes a first fixing unit 35 and a second fixing unit 38 which will be described later. Specifically, the gas nozzle mounting structure 1 according to the present embodiment is connected to a gas pipe 23 fixed to the bottom 3 e of the furnace 3 and a connection part 23 t of the gas pipe 23 via a pipe joint part 31. The gas nozzle 25, the pin 33 extending in the vertical direction inside the gas pipe 23, the first fixing portion 35 that fixes the upper end portion 33 b side of the pin 33 and the gas nozzle 25, and the lower end portion 33 c side of the pin 33 And a second fixing portion 38 to be fixed. For ease of explanation and understanding, in FIGS. 4 and 5, the upper surface of the refractory material 29 is flat and the gas nozzle 25 is sufficiently exposed. However, the upper surface of the refractory material 29 may be inclined, and a step may be provided.

  The gas pipe 23 is a cylindrical member formed of metal or the like. The gas pipe 23 is fixed so as to be fitted into the bottom 3e of the furnace 3 on the lower end 23e side. The gas pipe 23 includes a fitting portion 23a whose outer peripheral surface is surrounded by the bottom portion 3e, an upper extending portion 23b extending toward the combustion chamber 4 above the bottom portion 3e, and a wind box 21 below the bottom portion 3e. And a lower extending portion 23c extending toward the front. The outer peripheral surface of the upper extension 23 b is covered with a refractory material 29. The outer peripheral surface of the lower extension 23 c is exposed in the wind box 21. The upper end 23 d of the gas pipe 23 (that is, the upper end of the upper extension 23 b) is disposed inside the refractory material 29. With such a configuration, the gas pipe 23 can take in the gas flowing in the wind box 21 from the opening on the lower end 23e side and discharge it from the opening on the upper end 23d side.

  The gas nozzle 25 is a member formed of a metal or the like having a cylindrical inner cylinder portion 34 and an ejection portion 36 fixed so as to cover the upper portion of the inner cylinder portion 34. The inner cylinder portion 34 is a cylindrical member that extends upward so as to be continuous with the gas pipe 23, thereby allowing the gas that has passed through the gas pipe 23 to flow further upward. The ejection part 36 is a member that performs the direction change of the gas that has passed through the gas pipe 23 and the inner cylinder part 34 and ejects the gas to the combustion chamber 4.

  The inner cylinder part 34 of the gas nozzle 25 is connected to the connection part 25 t on the upper end part 23 d side of the gas pipe 23 via the pipe joint part 31 at the connection part 25 e on the lower end part side. The pipe joint part 31 is exhibiting the cylindrical shape formed, for example with the metal. The inner diameter of the pipe joint part 31 is larger than the outer diameters of the gas pipe 23 and the inner cylinder part 34. The outer peripheral surfaces of the connection portion 23 t of the gas pipe 23 and the connection portion 25 e of the inner cylinder portion 34 are in contact with the inner peripheral surface of the pipe joint portion 31. The connection part 23t of the gas pipe 23 is fixed to the lower end side of the pipe joint part 31 by welding or the like. The connection part 25e of the inner cylinder part 34 is not fixed to the upper end side of the pipe joint part 31 by welding or the like, and is detachably fixed so as to be inserted into the pipe joint part 31. A flow path FL1 extending upward from the lower end 23e of the gas pipe 23 to the upper end 34a of the inner cylinder part 34 is formed by the internal space of the gas pipe 23, the pipe joint part 31, and the inner cylinder part 34.

  The ejection part 36 of the gas nozzle 25 includes a main body part 36A that ejects gas in the ejection direction D1 (here, substantially horizontal direction), and a connection part 36B for connecting the main body part 36A to the inner cylinder part 34. ing. The connecting portion 36B has a cylindrical shape extending downward from the main body portion 36A, contacts the outer peripheral surface of the inner cylinder portion 34, and is fixed to the inner cylinder portion 34 by welding or the like. That is, by welding the vicinity of the lower end portion of the connecting portion 36B and the outer peripheral surface of the inner cylindrical portion 34 in a state where the inner peripheral surface of the connecting portion 36B of the ejection portion 36 and the outer peripheral surface of the inner cylindrical portion 34 are in contact with each other. The ejection part 36 and the inner cylinder part 34 are fixed. When the gas nozzle 25 is replaced, it is not necessary to release the fixing between the ejection part 36 and the inner cylinder part 34, and the ejection part 36 and the inner cylinder part 34 can be handled as one component. When fixing by welding, it may be firmly fixed so that welding is not removed due to wear or the like without considering the ease of removal at the time of replacement. In addition, the ejection part 36 and the inner cylinder part 34 may be integrally formed (for example, it may be formed as an integrally molded product). The main body portion 36A is provided so as to communicate with the inner cylinder portion 34, and extends from the upper end portion 34a side of the inner cylinder portion 34 in the ejection direction D1 (see FIG. 4). The main body portion 36A also extends in the width direction (see FIG. 5), whereby the width of the gas outlet JT formed at the distal end portion 36a of the main body portion 36A is wider than the diameter of the gas pipe 23. can do.

  A flow path FL2 is formed in the main body portion 36A by an internal space extending at least from the upper end portion 34a of the inner cylinder portion 34 in the ejection direction D1. The flow path FL2 of the main body portion 36A communicates with the flow path FL1 of the gas pipe 23, the pipe joint portion 31, and the inner cylinder portion 34, and opens at the distal end portion 36a of the main body portion 36A. The flow path FL2 is opened at the distal end portion 36a of the main body portion 36A, so that a gas ejection port JT is formed. The upper end side of the main body portion 36A is sealed by the upper wall portion 28, and the gas passing through the flow path FL1 is changed in direction by colliding with the lower surface 28a of the upper wall portion 28, and is ejected through the flow path FL2. It flows toward the direction D1, and is ejected from the ejection port JT. A gap for allowing gas to pass through is formed between the upper end portion 34 a of the inner cylinder portion 34 and the lower surface 28 a of the upper wall portion 28. In addition, although the outer surface of the ejection part 36 is not covered with the refractory material 29 and is exposed in the combustion chamber 4, at least the ejection port JT is exposed, and the gas nozzle 25 is removed for replacement. As long as it is possible, a part of the refractory material 29 may be covered.

  The pin 33 is a circular rod-shaped member that extends in the vertical direction over the entire area of the upper extending portion 23b, the fitting portion 23a, and the lower extending portion 23c so as to be along the inner wall surface of the gas piping 23 inside the gas piping 23. It is. The shape of the pin 33 is not particularly limited and may be a polygonal shape. The number of pins 33 is not particularly limited, but a plurality of pins 33 may be arranged in the circumferential direction inside the gas pipe 23, and two pins are arranged in the present embodiment. The pin 33 is made of, for example, metal and has a rod shape. The upper end portion 33 b of the pin 33 extends further upward than the upper end portion 23 d of the gas pipe 23 and extends to a position where it can come into contact with the inner wall surface 34 c of the inner cylinder portion 34. Further, the lower end portion 33c of the pin 33 extends downward from the lower end portion 23e of the gas pipe 23, and extends downward to such an extent that a welding allowance capable of fixing a support member 37 described later can be secured. In the present embodiment, the pin 33 extends straight in the up-down direction in a state where the pin 33 is in contact with the inner wall surface of the gas pipe 23 and the inner wall surface 34c of the inner cylinder portion 34 (or in a state where a slight gap is left). The position in the circumferential direction of the pair of pins 33 is not particularly limited. In the present embodiment, the pins 33 are arranged at positions that are opposed to each other in a direction orthogonal to the ejection direction D1 and are substantially 180 ° from each other when viewed from the vertical direction. ing.

  On the upper end portion 33 b side of the pin 33, a first fixing portion 35 that fixes the upper end portion 33 b side of the pin 33 and a portion inside the gas nozzle 25 is formed. In the present embodiment, the first fixing portion 35 is formed by directly joining the portion on the upper end portion 33 b side of the pin 33 to the gas nozzle 25. Specifically, the first fixing portion 35 is formed by welding and joining a predetermined portion on the upper end portion 33b side of the pin 33 and the inner wall surface 34c of the inner cylindrical portion 34 of the gas nozzle 25. It is comprised by the welding part. In the present embodiment, the welding portion constituting the first fixing portion 35 is formed at one place only in the region near the upper end portion 33 b of the pin 33. However, the welding portion constituting the first fixing portion 35 may be formed in any size at any position in the vertical direction of the joinable region 33t where the pin 33 and the inner cylinder portion 34 overlap. Here, the joinable region 33t refers to a region where the pin 33 and the inner cylindrical portion 34 can be joined by welding or the like. For example, the welded portion may be formed on the lower end side (or both the upper end side and the lower end side) of the joinable region 33t, or may be provided in substantially the entire region of the joinable region 33t, and scattered in a plurality of locations in the longitudinal direction. You may let them. Further, the first fixing portion 35 may be configured by a separate member that fixes the pin 33 and the gas nozzle 25 (for example, a clasp is attached to the pin 33 and the clasp is fixed to the inner cylinder portion 34). May be). The first fixing portion 35 having the above-described configuration is disposed inside the gas nozzle 25 and is not exposed to the combustion chamber 4 by being covered with the ejection portion 36 and the inner cylinder portion 34. Become.

  On the lower end portion 33c side of the pin 33, a second fixing portion 38 that fixes the lower end portion 33c side of the pin 33 and a predetermined fixing object is formed. The second fixing portion 38 fixes the object to be fixed and the lower end portion 33c side of the pin 33, thereby moving the pin 33 upward when the gas nozzle 25 is used, that is, moving the gas nozzle 25 upward. regulate. In the present embodiment, a support member (support portion) 37 is disposed below the gas pipe 23 as an object to be fixed to the pin 33. The support member 37 is configured in a shape and an arrangement so as to interfere with the lower end portion 23e of the gas pipe 23 in a state where the pair of pins 33 are connected to each other.

  The support member 37 is formed of, for example, metal and has a rectangular plate shape. The support member 37 has substantially rectangular main surfaces 37a and 37b opposed to each other as outer surfaces thereof. The support member 37 is disposed so that one main surface 37 a abuts the outer peripheral surfaces of the pair of pins 33 at least in a region below the lower end 23 e of the gas pipe 23. At this time, it arrange | positions so that the long side of the main surface 37a may be orthogonal to the direction (namely, up-down direction) where the pin 33 and the gas piping 23 are extended. Further, the upper end portion 37 c (the long side on the upper side of the main surface 37 a) of the support member 37 is in contact with the lower end portion 23 e of the gas pipe 23. In this state, the long side of the main surface 37 a is longer than the inner diameter of the gas pipe 23, and both end portions 37 e and 37 f facing the long side direction are arranged on the outer side in the radial direction of the gas pipe 23. Therefore, even if the support member 37 is pulled upward by the pin 33 due to an upward force acting on the gas nozzle 25, the upper end portion 37 c of the support member 37 interferes with the lower end portion 23 e of the gas pipe 23. By doing so, the movement of the pin 33 and the gas nozzle 25 can be regulated. The lower end portion 37d of the support member 37 is disposed above the lower end portion 33c of the pin 33, but may be disposed at the same position as or below the lower end portion 33c.

  The second fixing portion 38 is formed by directly joining the portion on the lower end portion 33c side of the pin 33 to the support member 37 arranged in this way. Specifically, the second fixing portion 38 is configured by a welded portion formed by welding and joining between a predetermined portion on the lower end portion 33 c side of the pin 33 and the main surface 37 a of the support member 37. ing. In the present embodiment, the welding portion constituting the second fixing portion 38 is formed only in one area only in the vicinity of the lower end portion 33 c of the pin 33. However, the welding portion constituting the second fixing portion 38 may be formed in any size at any position in the vertical direction of the joinable region 33e where the pin 33 and the support member 37 overlap. Here, the joinable region 33e refers to a region where the pin 33 and the support member 37 can be joined by welding or the like. For example, the welded portion may be formed on the upper end side (or both of the upper end side and the lower end side) of the joinable region 33e, or may be provided in substantially the entire region of the joinable region 33e, and scattered in a plurality of locations in the longitudinal direction. You may let them. The 2nd fixing | fixed part 38 which has the above structures is arrange | positioned on the outer side of the gas piping 23, and is exposed to the wind box 21. FIG.

  Next, a method for attaching and removing the gas nozzle 25 in the gas nozzle attachment structure 1 according to the present embodiment will be described.

  In order to attach the gas nozzle 25, first, the first fixed portion 35 is formed by joining the inner wall surface 34c of the inner cylinder portion 34 of the gas nozzle 25 and the upper end portion 33b side of the pin 33 by welding or the like. To do. At this time, if the upper end portion 33b side of the pin 33 is welded to the inner wall surface 34c of the inner cylinder portion 34 at the stage before the ejection portion 36 is fixed to the inner cylinder portion 34, the welding tool is placed inside the inner cylinder portion 34. Since it is not necessary to penetrate deeply, welding is easy. Subsequently, the gas nozzle 25 to which the pin 33 is joined is connected to the upper end portion 23 d of the gas pipe 23 through the pipe joint portion 31 in a state where the pin 33 is inserted into the gas pipe 23. At this time, a part of the pin 33 on the lower end portion 33 c side is in a state of being out of the gas pipe 23. The main surface 37a of the support member 37 is brought into contact with the portion on the lower end 33c side of the pin 33 that is outside the gas pipe 23, and the upper end 37c of the support member 37 is connected to the lower end of the gas pipe 23. 23e is contacted. In this state, the second fixing portion 38 is formed by joining the pin 33 and the support member 37 by welding or the like. Thus, the gas nozzle 25 is attached to the gas pipe 23 via the pin 33 by the first fixing portion 35 and the second fixing portion 38. In this state, even if the gas from the wind box 21 passes through the flow path FL1 in the gas pipe 23 and collides with the lower surface 28a of the upper wall portion 28 of the gas nozzle 25, the gas nozzle 25 is connected to the pin 33 and the support member. 37 is supported by the lower end 23e of the gas pipe 23 through 37. Thereby, it is possible to prevent the gas nozzle 25 from coming out of the gas pipe 23 (the pipe joint portion 31).

  In order to remove the gas nozzle 25, the second fixing portion 38 is first removed. Specifically, welding or the like between the support member 37 and the lower end portion 33 c side of the pin 33 is removed, and the pin 33 is removed from the support member 37. The gas nozzle 25 is removed from the gas pipe 23 by pulling the gas nozzle 25 together with the pin 33 upward from the gas pipe 23.

  Next, the operation and effect of the gas nozzle mounting structure 1 according to this embodiment will be described in comparison with the gas nozzle mounting structure according to another embodiment and the conventional gas nozzle mounting structure.

  6 is a schematic cross-sectional view of a gas nozzle mounting structure according to another embodiment, corresponding to FIG. 4, and FIG. 7 is an enlarged cross-sectional view of a fixing portion between the gas pipe and the pin shown in FIG. . As shown in FIG. 6, in the gas nozzle mounting structure 10 of the other embodiment as well, as in the gas nozzle mounting structure 1 of the present embodiment, the gas pipe 23 fixed to the bottom 3 e of the furnace 3, and the gas pipe 23. The gas nozzle 25 connected to the connection part 23t via the pipe joint part 31 and the pin 33 extending in the vertical direction inside the gas pipe 23 are provided. However, in the mounting structure 10 of another embodiment, the fixing structure of the pin 33 is different. Hereinafter, the fixing structure of the pin 33 in the mounting structure 10 of another embodiment will be described in detail.

  In the mounting structure 10 of another embodiment, a through hole 42 is provided in the upper wall portion 28 of the gas nozzle 25, and a pin 33 is inserted into the through hole 42. The upper end portion 33b side of the pin 33 drawn out from the through hole 42 is fixed to the outside of the upper wall portion 28 of the main body portion 36A by welding or the like, and a third fixing portion 39 is formed outside the upper wall portion 28. . The surplus portion 33a of the pin 33 protruding to the outside of the upper wall portion 28 through the through hole 42 is cut after the upper end portion 33b side of the pin 33 is fixed to the outside of the upper wall portion 28. Thus, the third fixing portion 39 is exposed to the combustion chamber 4 of the furnace 3 because it exists outside the upper wall portion 28 of the gas nozzle 25.

  Moreover, in the attachment structure 10 of other embodiment, it has the notch part 23f in the lower end part 23e of the gas piping 23, and the hook part 33d is formed in the lower end part 33c side of the pin 33. FIG. As shown in FIG. 7, the hooking portion 33d is formed by bending the lower end portion 33c side of the pin 33 in accordance with, for example, the notch position formed by the notch portion 23f. In this way, the hook 33 d of the pin 33 sandwiches and supports the gas pipe 23 between the notches 23 f formed at the lower end 23 e of the gas pipe 23.

  In order to mount the gas nozzle 25 in the mounting structure 10 of another embodiment, first, the pin 33 is passed through the through hole 42 of the upper wall portion 28 of the gas nozzle 25. The third fixing portion 39 is formed by drawing the upper end portion 33b side of the pin 33 from the through hole 42 to the outside of the upper wall portion 28 and joining it to the outside of the upper wall portion 28 by welding or the like. At this time, the surplus portion 33a of the pin 33 is cut. Subsequently, the gas nozzle 25 to which the pin 33 is joined is connected to the upper end portion 23 d of the gas pipe 23 through the pipe joint portion 31 in a state where the pin 33 is inserted into the gas pipe 23. At this time, a part of the pin 33 on the lower end portion 33 c side is in a state of being out of the gas pipe 23. Then, a portion on the lower end 33c side of the pin 33 that is outside the gas pipe 23 is bent so as to sandwich the gas pipe 23 in accordance with the position of the notch 23f of the gas pipe 23, thereby forming a hooking part 33d. To do. Thus, the gas nozzle 25 is attached to the gas pipe 23 via the pin 33 by the third fixing portion 39 and the hooking portion 33d.

  In order to remove the gas nozzle 25 in the mounting structure 10 of another embodiment, first, the welding between the upper end portion 33b side of the pin 33 and the outside of the upper wall portion 28 of the gas nozzle 25 is removed, and the pin 33 is removed. Remove from the gas nozzle 25. Then, the gas nozzle 25 is pulled out from the pin 33.

  For example, as a conventional gas nozzle mounting structure, the gas pipe (the gas pipe 23 and the inner cylinder 34 in the present embodiment are integrally formed so that the upper end protrudes from the bottom of the furnace 3 (the upper surface of the refractory material 29). And a gas nozzle provided in a gas pipe projecting into the combustion chamber 4 (consisting only of parts corresponding to the ejection portion 36 in the present embodiment). Is mentioned. In the conventional gas nozzle mounting structure, the gas nozzle and the upper end of the gas pipe are connected, and the gas nozzle and the gas pipe are fixed by welding or the like at the connecting part. At the time of replacement of the gas nozzle, the welding of the connecting portion is removed. However, since the connection portion between the gas nozzle and the gas pipe is exposed in the combustion chamber 4, the gas nozzle may come off when the connection portion is directly damaged by the fluid medium. As described above, the gas nozzle dropped from the gas pipe falls to the discharge port 3d along the ejection direction D1, and the fallen gas nozzle may be tripped by a conveyor or the like. Further, at the time of replacement of the gas nozzle, it is necessary to dig up the vicinity of the upper surface of the refractory material 29 to ensure a sufficient space in order to remove the welding of the connecting portion. Therefore, the replacement work may not be easily performed.

  On the other hand, according to the gas nozzle mounting structure 10 shown in FIG. 6, the gas pipe 23 embedded in the bottom portion (the bottom portion 3 e and the refractory material 29) of the furnace 3 and the gas protruding into the combustion chamber 4 of the furnace 3. The connection part (pipe joint part 31) with the nozzle 25 is arrange | positioned in the bottom part. Accordingly, it is possible to prevent the gas nozzle 25 from coming off at the connecting portion. Therefore, it is possible to prevent the gas nozzle 25 from dropping from the gas pipe 23. Moreover, the gas nozzle 25 can be removed by canceling | releasing the connection in a connection part. As described above, the gas nozzle 25 can be prevented from falling off, and the gas nozzle 25 can be easily replaced.

  Here, as described above, in the mounting structure 10 of the other embodiment, the third fixing portion 39 that fixes the gas nozzle 25 and the upper end portion 33b side of the pin 33 is the upper wall portion 28 of the gas nozzle 25. Is present outside. That is, the third fixed portion 39 is exposed to the combustion chamber 4 of the furnace 3. For this reason, during operation of the furnace 3, the gas nozzle 25 and the third fixed portion 39 are exposed to a fluid medium that flows vigorously. Therefore, the gas nozzle 25 and the third fixing portion 39 are deteriorated due to wear, and the gas nozzle 25 may drop from the gas pipe 23 depending on the fixing strength of the third fixing portion 39.

  Moreover, the replacement | exchange of the gas nozzle 25 in the attachment structure 10 of other embodiment has room for improvement further. Specifically, it is necessary to cut the surplus portion 33a of the pin 33 in order to attach the gas nozzle 25. In order to remove the gas nozzle 25, it is necessary to remove the welding between the upper end portion 33 b of the pin 33 and the gas nozzle 25, remove the pin 33 from the gas nozzle 25, and then remove the gas nozzle 25.

  On the other hand, according to the mounting structure 1 of the gas nozzle 25 according to the present embodiment, the first fixing portion 35 that fixes the upper end portion 33 b side of the pin 33 and the gas nozzle 25 is not exposed to the combustion chamber 4. Therefore, even if the outer surface of the gas nozzle 25 is worn, it is possible to prevent the first fixed portion 35 from being worn. Therefore, since the state where the gas nozzle 25 is supported by the pin 33 can be maintained, it is possible to prevent the gas nozzle 25 from dropping from the gas pipe 23. Further, since the upper end portion 33b side of the pin 33 is fixed to the gas nozzle 25 and the lower end portion 33c side of the pin 33 is fixed to the lower end portion 23e side of the gas pipe 23, the pin 33 is fixed to the lower end portion 33c side. The gas nozzle 25 can be removed together with the pin 33 by an easy operation of simply removing it. As described above, the dropout can be prevented and the gas nozzle 25 can be easily replaced.

  Moreover, according to the attachment structure 1 of the gas nozzle 25 according to the present embodiment, the second fixing portion 38 that fixes the lower end portion 33 c side of the pin 33 is disposed outside the gas pipe 23. For example, when the second fixing portion 38 is disposed inside the gas pipe 23 (for example, when the lower end portion 33c of the pin 33 is welded to the inner wall surface of the gas pipe 23), a welding nozzle is used at the time of attachment. It is necessary to enter the gas pipe 23, and a tool for removing welding needs to enter the gas pipe 23 at the time of removal. On the other hand, when the 2nd fixing | fixed part 38 is arrange | positioned on the outer side of the gas piping 23, attachment and removal of the gas nozzle 25 can be performed on the outer side of the gas piping 23, and work with a welding nozzle or a removal tool This makes it easier to replace the gas nozzle 25 than in the prior art.

  Further, according to the mounting structure 1 of the gas nozzle 25 according to the embodiment, the first fixing portion 35 is formed by joining the inner wall surface 34 c of the gas nozzle 25 and the upper end portion 33 b side of the pin 33. . For this reason, the 1st fixing | fixed part 35 which is not exposed to the combustion chamber 4 can be formed easily. That is, the gas nozzle 25 can be attached by a simple operation of bringing the upper end 33b side of the pin 33 into contact with the inner wall surface 34c of the gas nozzle 25 and joining them by welding or the like.

  The preferred embodiments of the present invention have been described above. However, the present invention is not necessarily limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  For example, the fixing method in the above embodiment is not limited to welding, and may be fixed using a screw structure or the like.

  The pin 33 is not limited to a rod shape, and may have various shapes as long as the gas nozzle 25 can be supported.

The support member 37 is not limited to a substantially rectangular parallelepiped plate shape, and may have various shapes as long as the pin 33 can be supported. For example, a bar-like member extending in the horizontal direction may be used.

  The second fixing portion 38 is not limited to the one that fixes the pin 33 and the separate member. For example, after inserting the pin 33 into the gas pipe 23, as shown in FIG. 7, the second fixing portion 38 may be formed by bending the lower end portion 33c of the pin 33 to form the hooking portion 33d. . In this case, when removing the gas nozzle 25, the hook 33d on the lower end 33c side of the pin 33 can be returned straight or can be removed by cutting. Moreover, you may weld-join the pin 33 and the gas piping 23 directly.

  DESCRIPTION OF SYMBOLS 1 ... Gas nozzle mounting structure, 3 ... Furnace, 3e ... Bottom part, 4 ... Combustion chamber, 23 ... Gas piping, 23d ... Upper end part (upper end), 23e ... Lower end part (lower end), 25 ... Gas nozzle, 29 ... Fire resistance Material (bottom part), 31 ... Pipe joint part (connection part), 34c ... Inner wall surface, 33 ... Pin, 33b ... Upper end part (upper end), 33c ... Lower end part (lower end), 35 ... First fixing part (fixing part) ), 37... Support member (support part), 38... Second fixing part (fixing part).

Claims (6)

A gas pipe embedded in the bottom of a furnace having a combustion chamber and extending upward toward the combustion chamber;
A gas nozzle connected to the upper end side of the gas pipe and projecting into the combustion chamber of the furnace,
A gas nozzle mounting structure in which a connecting portion between the gas pipe and the gas nozzle is disposed in the bottom. A fixing portion for fixing the gas nozzle so as not to move with respect to the furnace;
The gas nozzle mounting structure according to claim 1, wherein the fixed portion is not exposed in the combustion chamber. Further comprising a pin extending in the vertical direction inside the gas pipe,
The upper end side of the pin is fixed to the gas nozzle,
The lower end side of the pin is fixed on the lower end side of the gas pipe,
The gas nozzle mounting structure according to claim 2, wherein the fixing portion includes a first fixing portion that fixes an upper end side of the pin and the gas nozzle.   The gas nozzle mounting structure according to claim 3, wherein the fixing portion includes a second fixing portion that fixes a lower end side of the pin, and the second fixing portion is disposed outside the gas pipe. .   The gas nozzle mounting structure according to claim 3 or 4, wherein the first fixing portion is formed by joining an inner wall surface of the gas nozzle and an upper end side of the pin.   The gas nozzle mounting structure according to claim 4, wherein the second fixing portion fixes the lower end side of the pin to a support portion disposed in a region below the lower end portion of the gas pipe.

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