JP2009256930A - Demolition method for chimney - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a demolition method for a chimney capable of efficiently demolishing the lower section of the chimney in which a streamlining plate and a hopper are installed while preventing harmful substances from being dispersed to the outside. <P>SOLUTION: A step of demolishing the lower section of a chimney comprises: a hopper section heat insulation layer removal step of removing the heat insulation layers 9, 10 of a hopper section 22 in such a state that the inside 1a of the chimney is brought into a negative pressure by sucking the air inside the chimney 1; a first internal air measuring step of measuring the mass of the harmful substances in the air inside the chimney after the hopper section heat insulation layer removal step; a hopper demolition step of demolishing a hopper 4; a straightening plate section heat insulation layer removal step of removing the heat insulation layers 7, 8, 9 of a straightening plate section 21 in such a state that the inside 1a of the chimney 1 is brought into a negative pressure by sucking the air inside the chimney; a second internal air measuring step of measuring the mass of the harmful substances in the air inside the chimney 1 after the straightening plate section heat insulation layer removal step; a straightening plate demolishing step of demolishing the straightening plate 3; and an outer tube demolishing step of demolishing the straightening plate 21 and the outer tube 5 of the hopper section 22. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a chimney dismantling method for disassembling a chimney in which a heat insulating layer of an inner cylinder is disposed on the radially inner side of an outer cylinder.

  Conventionally, some chimneys such as plants and incinerators are constructed by disposing a heat insulating layer of an inner cylinder inside a steel outer cylinder in the radial direction. Some heat insulating layers are formed by lining a heat insulating material on the inner surface of an outer cylinder, or by stacking refractory bricks.

  On the other hand, a heat insulating layer is formed using a heat insulating material containing asbestos, or dioxin adheres to the inner surface forming the flue of the heat insulating layer (inside the chimney) when the chimney is used. May contain harmful substances. Conventionally, when disassembling this type of chimney, the work area is isolated by covering the chimney with a plastic sheet or the like, and this work area is brought into a negative pressure state, thereby containing harmful substances generated during dismantling. The dust was prevented from scattering to the surrounding environment (outside).

  However, large chimneys having a height of, for example, about 100 m or more and a caliber (chimney diameter) of, for example, 5 m or more are frequently used in plants, incinerators, and the like, particularly when such large chimneys are dismantled. It is difficult to cover the entire chimney with a plastic sheet or to maintain the work area under negative pressure, and additional measures against strong winds are required. There is a problem that it may not be possible to secure the cost, or the cost of dismantling work is increased and the construction period is prolonged.

  On the other hand, in the chimney dismantling method (chimney dismantling method) disclosed in Patent Document 1, a stack for cleaning the flue cleaning device is installed on the outer cylinder of the chimney, and the cleaning device for the flue is introduced into the flue using a winch and a wire. However, a hermetic cover is installed at the top of the flue so that harmful substances adhering to the inner surface of the heat insulation layer are cleaned in advance with the flue cleaning apparatus in a state where the inside of the chimney is cut off from the surrounding environment. Also, dust is scattered in the surrounding environment by installing a dust collector at the flue opening (flue port) formed on the lower side of the chimney to suck the air inside the flue and cutting the chimney with a wire saw. To prevent that. Then, the chimney cut portion (chimney block piece) roughly cut in this way is suspended on the ground with a crane together with the cleaning device installation base, and further disassembled in the work room.

In the chimney dismantling method (structure dismantling method) disclosed in Patent Document 2, a stage scaffold that can be moved up and down by a second crane is arranged at the chimney cutting part while the top side of the chimney is suspended by a first crane. Then, the chimney is cut into a ring shape by a cutting device mounted on the stage scaffold. At this time, before cutting, attach the top lid to the top of the chimney, suck the air inside the chimney (the air inside the chimney), and cut in a state where the cutting work area is isolated by the sealed booth mounted on the first crane To prevent dust scattering.
JP 2002-121906 A JP 2004-36158 A

  By the way, as shown in FIG.1 and FIG.2, the chimney 1 is made of steel for rectifying and discharging smoke introduced into the inside 1a from the outside 1b through the flue opening 2 to the inside 1a on the lower 1d side. The flow straightening plate 3, the flow straightening plate 3 and the flue opening 2 are provided below, receiving rainwater entering from the top 1 c of the chimney 1, falling objects such as firewood, and connecting the falling objects to the tube opening 4 a. There is one constructed by installing a steel hopper 4 for discharging to the outside 1b through a discharge pipe (not shown). The rectifying plate 3 is supported by a steel reinforcing beam 6 whose end is connected to the outer cylinder 5, and the rectifying plate 3 and the reinforcing beam 6 have surfaces 3 a and 6 a covered with heat insulating layers 7 and 8. . Further, the hopper 4 is covered with a heat insulating layer 10 on the inner surface 4 b facing upward so as to be connected to a heat insulating layer 9 disposed on the radially inner side of the outer cylinder 5.

  For this reason, the part (chimney upper part 20) located above the baffle plate 3 cuts the chimney block piece 11 (cuts the chimney 1 in a ring shape) and disassembles it like the conventional chimney dismantling method. However, the chimney lower part (the current plate part 21 and the hopper part 22) is provided with the current plate 3 (and the reinforcing beam 6) and the hopper 4, so that the chimney block piece 11 is similar to the chimney upper part 20. There was a problem that it could not be cut out and disassembled.

  When disassembling such chimney lower parts 21 and 22, for example, an operator enters the inside 1 a of the chimney 1, installs a temporary scaffold (not shown) in the inside 1 a of the chimney lower parts 21 and 22, and rectifies At the stage where all of the heat insulating layers 7 to 10 of the plate portion 21 and the hopper portion 22 are removed by lifting, the rectifying plate 3, the reinforcing beam 6, and the hopper 4 are separated from the outer cylinder 5 and disassembled, and finally the outer cylinder 5 is cut into rings. It was cut into a shape and dismantled. However, when the chimney lower parts 21 and 22 are disassembled in this way, the hopper 4 is in the way, so that temporary scaffolding can be continuously installed from the lower part 1d of the chimney 1 to the hopper part 22 and the current plate part 21. In other words, a suspended temporary scaffold supported by the chimney 1 (outer cylinder 5) must be installed above the hopper 4, and a great deal of labor and time is required for assembling the temporary scaffold and thus dismantling the chimney 1. There was a problem of requiring.

  In view of the above circumstances, the present invention can efficiently perform dismantling of the lower part of the chimney in which a current plate and a hopper are installed while reliably preventing harmful substances (dust) from diffusing to the outside. An object is to provide a chimney dismantling method.

  In order to achieve the above object, the present invention provides the following means.

  The chimney disassembly method of the present invention is provided with a heat insulating layer of the inner cylinder disposed on the radially inner side of the outer cylinder, the surface is covered with the heat insulating layer, and the smoke introduced from the flue opening is rectified and discharged. A method of disassembling a chimney constructed by installing a rectifying plate and a hopper provided below the rectifying plate and having an inner surface facing upward covered with a heat insulating layer inside the lower side, wherein the chimney is The part above the current plate is the chimney upper part, the part from the hopper to the lower part of the chimney is the hopper part, and the part between the chimney upper part and the hopper part is the current plate part A chimney upper part dismantling process for dismantling the chimney upper part, and a chimney lower part dismantling process for dismantling the hopper part and the rectifying plate part, wherein the chimney lower part dismantling process sucks the air inside the chimney and The hopper section in a negative pressure state A hopper part heat insulation layer removal step for removing the heat insulation layer, a first internal air measurement step for measuring the amount of harmful substances in the internal air of the chimney after the hopper part heat insulation layer removal step, and the first internal air measurement A hopper dismantling step for disassembling the hopper after the step, and a rectification for removing the heat insulating layer of the rectifying plate portion in a state where the air inside the chimney is sucked and the inside is made negative pressure after the hopper disassembling step After the plate heat insulating layer removing step and the rectifying plate heat insulating layer removing step, after the second internal air measuring step for measuring the amount of harmful substances in the internal air of the chimney, and after the second internal air measuring step, A rectifying plate disassembling step of disassembling the rectifying plate, and an outer cylinder disassembling step of disassembling the outer cylinder of the rectifying plate portion and the hopper portion are provided.

  In the present invention, in the chimney upper part dismantling step, the chimney upper part is cut into, for example, a ring shape, and the chimney block piece is cut out and disassembled. In addition, the chimney lower part (rectifier plate part and hopper part) that cannot be cut out and disassembled from the chimney block piece is the hopper part heat insulating layer removing process, the rectifying plate part heat insulating layer removing process, the hopper dismantling process and the rectifier Separate the plate disassembly process, disassemble the hopper at the stage where the heat insulating layer of the hopper part is removed, remove the heat insulating layer of the rectifying plate part at the stage of dismantling the hopper, and remove the heat insulating layer of the rectifying plate part Dismantle the rectifying plate (and the reinforcing beam).

  And when removing the heat insulation layers of the hopper part and the rectifying plate part respectively, the air inside the chimney is sucked to make the inside a negative pressure, and for example, the heat insulation layer is formed by an operator wearing equipment of work level 1 for asbestos treatment. By removing the suspension, it is possible to reliably prevent the asbestos (hazardous substance) from diffusing outside and to remove the heat insulating layer.

  In addition, after the hopper heat insulation layer removal step, the amount of harmful substances in the internal air is measured in the first internal air measurement step, and it is confirmed that the inside of the chimney is not a harmful environment. It is possible to dismantle the hopper by an operator wearing normal work equipment without sucking air, and it is possible to efficiently dismantle the hopper.

  Furthermore, by disassembling the hopper prior to the rectifying plate heat insulating layer removing step, it is possible to install temporary scaffolding continuously from the lower part of the chimney to the hopper portion and the rectifying plate portion in the rectifying plate heat insulating layer removing step. Thus, the assembly work of the temporary scaffold can be facilitated and the heat insulating layer of the rectifying plate portion can be efficiently removed.

  In addition, after the rectifying plate heat insulating layer removing step, the amount of harmful substances in the internal air is measured in the second internal air measuring step, and it is confirmed that the inside of the chimney is not harmful environment. The rectifying plate (and the reinforcing beam) can be disassembled by an operator wearing normal work equipment without sucking the internal air. Further, at this time, it is possible to dismantle the current plate using a temporary scaffold continuously installed from the lower part of the chimney to the hopper part and the current plate part. Thereby, it becomes possible to efficiently dismantle the current plate (and the reinforcing beam).

  And since only an outer cylinder remains by disassembling a baffle plate and a hopper as mentioned above, it becomes possible to disassemble an outer cylinder easily at an outer cylinder disassembly process.

  Further, in the chimney disassembly method of the present invention, the chimney lower part disassembly step includes forming a passage opening through the hopper portion before the hopper portion heat insulation layer removing step, and passing the passage opening through the passage opening portion. It is desirable to provide a security room installation step of installing a security room connected to the inside of the chimney outside the chimney.

  In this invention, an operator can enter and exit the chimney and carry in and out temporary equipment through the passage opening and the security room. This makes it possible to clean, for example, workers and temporary equipment coming out of the chimney in the security room, and to isolate (compartment) the chimney interior from the outside in the security room. Therefore, it is possible to reliably prevent harmful substances inside the chimney from diffusing to the outside.

  According to the chimney dismantling method of the present invention, the heat insulating layer of the hopper part and the rectifying plate part is removed by being divided into the hopper part heat insulating layer removing step and the rectifying plate part heat insulating layer removing step, and the rectifying plate part heat insulating layer removing step; Prior to the rectifying plate disassembly process, the hopper is disassembled in the hopper disassembly process, and the amount of harmful substances in the internal air of the chimney is confirmed in two steps in the first internal air measurement process and the second internal air measurement process. By disassembling the hopper and the rectifier plate individually in the hopper dismantling process and the rectifying plate dismantling process with safety ensured, the dismantling of the lower part of the chimney where the rectifying plate and hopper are installed is harmful to the outside It becomes possible to carry out efficiently while preventing the diffusion of substances.

  Hereinafter, a chimney disassembly method according to an embodiment of the present invention will be described with reference to FIGS. 1 to 10. This embodiment is a chimney demolition method capable of efficiently dismantling a chimney constructed containing harmful substances while reliably preventing the harmful substances (dust containing dusts) from diffusing into the surrounding environment. It is about. In the present embodiment, the description will be made assuming that the harmful substance is asbestos.

  As shown in FIGS. 1 and 2, the chimney 1 to be disassembled by the chimney disassembly method of the present embodiment is supported by a foundation 1 e embedded in the ground, and the steel outer cylinder 5 and the outer cylinder 5 An inner cylinder heat insulating layer 9 is provided on the inner surface of the outer cylinder 5 and is formed by lining a heat insulating material on the inner surface of the outer cylinder 5. In addition, the chimney 1 of the present embodiment gradually has an outer diameter of the chimney 1 and a diameter of the flue formed by the heat insulating layer 9 (diameter of the inside 1a of the chimney 1) as it goes from the lower part 1d in the direction of the axis O1 to the top part 1c. For example, the chimney is a large chimney having a height of 85 m, a maximum outer diameter of 6.5 m, and a minimum outer diameter of 4 m. Furthermore, the thickness of the outer cylinder 5 is 9 mm, the thickness of the heat insulating layer 9 is 60 mm, and the heat insulating material containing asbestos is used for the heat insulating layer 9.

  Further, the chimney 1 of the present embodiment is formed with a flue opening (flue port) 2 for introducing smoke from the outside 1b to the inside 1a of the chimney 1 on the lower 1d side. Further, in the interior 1a on the lower 1d side of the chimney 1, there are a rectifying plate 3 for rectifying the smoke introduced from the flue opening 2 and discharging it from the top 1c, and below the rectifying plate 3 and the flue opening 2 And a hopper 4 for receiving rainwater that has entered from the top 1c of the chimney 1 and falling objects such as a kite and discharging it to the outside 1b.

 The rectifying plate 3 is configured by a pair of rectangular plate-like steel plates that extend in the direction of the axis O1 of the chimney 1 and are arranged in parallel in the radial direction. In addition, in the interior 1a of the chimney 1, steel reinforcing beams 6 extending in the radial direction with both ends connected to the outer cylinder 5 are installed, and the rectifying plates 3 (a pair of steel plates) are respectively connected to one side end. Is connected to the inner surface of the outer cylinder 5 and the other end is connected to the reinforcing beam 6 so as to be orthogonal to the reinforcing beam 6 (see FIG. 6). Further, the current plate 3 and the reinforcing beam 6 are lined with a heat insulating material containing asbestos on the respective surfaces 3 a and 6 a and covered with the heat insulating layers 7 and 8.

  On the other hand, the hopper 4 is made of steel and is formed in a funnel shape. The tube port 4a is arranged downward, the upper end is connected to the inner surface of the outer tube 5, and the axis O1 of the chimney 1 and the axis of each other are coaxial. It is installed in a state of being placed above. In addition, the hopper 4 is lined with an insulating material containing asbestos on the inner surface 4 b facing upward, that is, the surface facing the top 1 c side of the chimney 1, and is covered with the heat insulating layer 10. The heat insulating layer 10 is formed so as to be connected to the heat insulating layer 9 disposed on the radially inner side of the outer cylinder 5.

  Here, in the chimney 1 of the present embodiment configured as described above, a portion above the rectifying plate 3 is a chimney upper portion 20, and a portion from the hopper 4 to the lower portion 1d of the chimney 1 is a hopper portion 22. A portion where the rectifying plate 3 and the reinforcing beam 6 are installed is located between the chimney upper portion 20 and the hopper portion 22, and is a rectifying plate portion 21.

  And when such a chimney 1 is disassembled, in this embodiment, the chimney upper part 20 and the chimney lower part (rectifier plate part 21 and hopper part 22) are divided and disassembled. In the dismantling of the chimney upper part 20 (chimney upper part disassembling process) performed prior to the chimney lower parts 21 and 22, the top part 1c is sequentially cut and separated into, for example, every 3.5 m in height (for example, 3. The chimney block piece 11 is cut out every 5 m and the chimney 1 is disassembled. At this time, as shown in FIG. 1, dismantling work is performed using a crane 12, a temporary scaffold 13 provided so as to cover the entire circumference of the chimney 1, a dust collection hat 14, and a chimney block piece processing yard 15. Do. When disassembling the chimney upper part 20, the flue opening 2 formed on the lower part 1d side of the chimney 1 is previously closed using a closing member such as a plastic sheet.

  The dust collection hat 14 is formed in a substantially disk shape with an outer diameter equal to or greater than the maximum outer diameter of the chimney 1. As shown in FIG. 3, for example, a steel material 16 such as H-shaped steel and a lower surface of the steel material 16 A suspension base 18 composed of a substantially disc-shaped isolation panel 17 that is attached, an elastic member 19 such as a rubber plate attached to the lower surface of the isolation panel 17, an internal dust collector 25 supported by the steel material 16, and An external dust collector 26 is provided.

  Further, the internal dust collector 25 is disposed radially inward with respect to the external dust collector 26, and the dust collection hat 14 is installed on the top portion 1c of the chimney 1 with the chimney 1 and the axis O1 of the chimney 1 arranged substantially coaxially. In the state (the state of FIG. 3), a duct 25 a penetrating the isolation panel 17 is provided so as to be disposed in the interior 1 a of the chimney 1. The external dust collector 26 is provided so that a duct 26a penetrating the isolation panel 17 is arranged on the outside 1b of the chimney 1 with the dust collection hat 14 installed at the top 1c of the chimney 1, and the chimney 1 is cut into rings. The suction port of the duct 26a is provided in the vicinity of the cutting line S that is cut and separated into a shape.

  When the dust collection hat 14 is installed on the top 1c of the chimney 1, the elastic member 19 is in close contact with the top 1c to seal the inside 1a of the chimney 1. Further, when the internal dust collector 25 is driven in this state, the internal air of the closed chimney 1 is sucked, and the inside 1a of the chimney 1 can be brought into a negative pressure state with respect to the outside 1b. Furthermore, when the external dust collector 26 is driven, external air near the cutting line S can be sucked.

  The chimney block piece processing yard 15 is for cutting and separating the chimney 1 in a ring shape and receiving and processing the chimney block pieces 11 suspended by the crane 12 together with the dust collecting hat 14. The chimney block piece processing yard 15 suspends and removes the heat insulating layer 9 from the chimney block piece 11, and also removes asbestos by removing the asbestos by subjecting the outer cylinder 5 of the chimney block piece 11 to the cleansing process. It is comprised so that the outer cylinder 5 of the block piece 11 can be carried out to the exterior 1b. In addition, this chimney block piece processing yard 15 is provided with a dust collector that sucks the internal air, and while the dust collector is driven, the inside is in a negative pressure state, and also collects dust scattered by the suspending operation and the keren operation, Asbestos is configured not to diffuse to the outside 1b.

  And in the chimney upper part dismantling process which demolishes the chimney upper part 20, as shown in FIG.1 and FIG.3, the temporary scaffold 13 is first installed around the chimney 1. FIG. Next, a wire 27 is attached to the dust collection hat 14, and the dust collection hat 14 is lifted by the crane 12 and installed on the top 1 c of the chimney 1 so that the axis O <b> 1 is arranged substantially coaxially. Further, the worker M attaches the wire 28 to the suspension base 18 (steel material 16) of the dust collection hat 14 and the chimney 1 with a predetermined tension, and fixes the dust collection hat 14 to the chimney 1. When the dust collecting hat 14 is thus installed, the elastic member 19 is in close contact with the top 1c of the chimney 1 and the inside 1a (the flue) of the chimney 1 is covered with the isolation panel 17, and the inside 1a of the chimney 1 is placed. Is sealed with a dust collecting hat 14.

  Next, the internal dust collector 25 is driven, and suction of the internal air of the chimney 1 is started. Thereby, the inside 1a of the chimney 1 in a state where the flue opening 2 on the lower 1d side is closed with the closing member is in a negative pressure state.

  Next, the worker M drives the external dust collector 26 of the dust collection hat 14 to start sucking the external air in the vicinity of the cutting line S, and cuts the outer cylinder 5 along the cutting line S using, for example, a gas burner. To do. Then, while spraying the dust scattering preventive agent from the outside 1b of the chimney 1 to the exposed heat insulating layer 9, the heat insulating layer 9 is suspended along the cutting line S using, for example, a breaker. At this time, the heat insulation layer 9 is suspended so as to drop into the interior 1 a of the chimney 1, so that the exterior 1 b and the interior 1 a of the chimney 1 communicate with each other, and toward the interior 1 a held in a negative pressure state by the internal dust collector 25. External air flows in. Thereby, the dust containing asbestos is sucked into the inside 1a of the chimney 1 together with the external air, and the dust (asbestos) sucked into the inside 1a is sucked together with the internal air and collected by the internal dust collector 25 that is continuously driven. Is done. Further, since the dust scattering preventive agent is also sucked into the interior 1a together with the external air, the diffusion of the dust in the interior 1a is suppressed, and the dust is surely collected by the internal dust collector 25 also from this point.

  In addition, there is a possibility that dust generated by removing the heat insulating layer 9 may be scattered to the outside 1b until the outside 1b and the inside 1a of the chimney 1 communicate with each other. By performing the suction of the external air near the cutting line S by the external dust collector 26, dust scattering to the external 1b is prevented.

  Further, the chimney block piece 11 is cut and separated by removing the heat insulating layer 9 along the cutting line S. At this time, the chimney block piece 11 is supported by the crane 12 via the wire 27. 14 are integrally connected to each other by a wire 28, and are supported by the crane 12 together with the dust collecting hat 14.

  The chimney block piece 11 cut and separated in this way is suspended from the ground by the crane 12, removed the dust collecting hat 14 together with the wire 28, and carried into the chimney block piece processing yard 15. Further, in the chimney block piece processing yard 15, the chimney block piece 11 has the heat insulation layer 9 removed therefrom, and the outer cylinder 5 from which the heat insulation layer 9 has been removed is subjected to keren treatment to remove asbestos.

  The dust collecting hat 14 removed from the chimney block piece 11 is again installed on the top 1c of the chimney 1 with the crane 12 (the top 1c of the new chimney 1 formed after cutting the chimney block piece 11), and the next chimney block. Used to cut out the piece 11. Then, the chimney block piece 11 is cut out from the chimney 1 and the operation of processing the chimney block piece 11 in the chimney block piece processing yard 15 is sequentially repeated, whereby the chimney upper part 20 is disassembled. And even when asbestos is contained in the heat insulating layer 9, the chimney block piece 11 is cut out in a state in which dust is surely prevented from being scattered, and the processing in the chimney block piece processing yard 15 is performed. The chimney 1 is disassembled while ensuring the reliability and safety for the worker M. Moreover, since the cut-out of the chimney block piece 11 and the processing of the chimney block piece 11 are performed in a flow operation, the chimney upper part 20 is efficiently dismantled by the chimney upper part dismantling process.

  On the other hand, the lower part of the chimney (the current plate part 21 and the hopper part 22) is provided with the current plate 3 and the reinforcing beam 6 and the hopper 4 in the inside 1a of the chimney 1, so that the chimney is shaped like a chimney like the upper part 20 of the chimney. The block piece 11 cannot be cut out and disassembled.

  In contrast, in the present embodiment, as shown in FIG. 4, when the chimney lower portions 21 and 22 are disassembled (in the chimney lower portion dismantling process), first, a plastic sheet that closes the flue opening 2 or the like The closing member is removed, and the lower portion 1d side of the outer cylinder 5 where the heat insulating layer 9 of the hopper 22 is not disposed is blown to form the passage openings 30 (two in this embodiment). In addition, temporary materials and equipment are carried into the interior 1 a of the chimney 1 from the flue opening 2 and the traffic opening 30, and a temporary scaffold 31 extending upward from below the hopper 4 through the tube port 4 a of the hopper 4 is installed. Assemble the temporary scaffold 32 above. Further, the passage opening 30 is formed and the temporary scaffolds 31 and 32 are assembled, and the security room 33 is installed on the outside 1b of the chimney 1 (security room installation process).

  As shown in FIGS. 4 and 5, the security room 33 has a double inner / outer structure, and the outer shell 34 has a smoke-proof sheet 34b and a steel folded plate 34c (roof roof) as a temporary scaffold 34a as a measure against wind and rain. ) And attached. The inner shell 35 is formed of a plastic sheet 35a having a thickness of 0.1 mm or more, for example. Further, as shown in FIG. 6, the security room 33 is formed by dividing the interior into three chambers in the order of a front chamber 36, a cleaning chamber 37, and a rear chamber 38, and the front chamber 36 has a passage opening 30. It is installed so that it may connect with the inside 1a of the chimney 1. At this time, the chambers 36 to 38 are partitioned using a plastic sheet or the like so as to be able to communicate / block.

  This security room 33 is used as a passage for the worker M who works in the interior 1a of the chimney 1, and when the worker M goes out of the interior 1a to the exterior 1b, the work room is taken off in the front chamber 36, and the washing room 37 The asbestos can be prevented from diffusing to the outside 1b by washing the body and wearing clothes in the rear chamber 38. The security room 33 is also used as a carry-out path for carrying out the hanging glass of the heat insulating layers 7 to 10 from the inside 1a by, for example, a forklift. Asbestos can be prevented from diffusing to the outside 1b by washing the forklift.

  Next, when the security room 33 is installed, as shown in FIG. 7, the flue opening 2 is closed again with a closing member 39 such as a plastic sheet, and the dust collection hat 14 is installed on the top 1 c of the chimney 1. To do.

  Next, the operator M wearing the asbestos processing level 1 equipment in the state in which the dust collector 25 for the inside of the dust collection hat 14 is driven to suck the air inside the chimney 1 to make the inside 1a have a negative pressure, The heat insulating layer 9 covering the inner surface of the outer cylinder 5 of the portion 22 and the heat insulating layer 10 covering the inner surface 4b of the hopper 4 are suspended and removed while spraying the dust scattering preventing agent (hopper heat insulating layer removing step). At this time, the hanger of the heat insulation layers 9 and 10 is sequentially discharged to the lower part 1d of the chimney 1 through the tube port 4a of the hopper 4 and packed in a bag, and the hung up hulls packed in the bag are sequentially opened using a forklift. 30 and the security room 33 to the outside 1b. In addition, this hull is processed as specially controlled industrial waste. Then, at the stage where all of the heat insulating layers 9 and 10 of the hopper 22 are suspended and removed, a dust scattering preventing agent is sprayed on the outer cylinder 5 and the hopper 4 of the hopper 22 and remains attached to the outer cylinder 5 and the hopper 4. The asbestos to be solidified.

  Next, after removing the heat insulating layers 9 and 10 of the hopper 22, the first measurement of the amount of asbestos dust (amount of harmful substances) in the internal air of the chimney 1 is performed in the present embodiment (first internal air measurement step). . Then, after confirming that the amount of asbestos dust in the internal air is a value capable of releasing the separation of the chimney 1 by the first internal air measurement step, the driving of the internal dust collector 25 of the dust collection hat 14 is performed. And the dust collecting hat 14 is removed from the top 1c of the chimney 1. Moreover, while removing the blocking member 39 blocking the flue opening 2, the worker M enters the inside 1 a and dismantles and removes the temporary scaffolds 31 and 32 installed in the hopper 22.

  Further, as shown in FIG. 8, the rolling scaffold 40 is assembled below the hopper 4. The dismantled temporary scaffolds 31 and 32 (scaffold) are washed in the security room 33 and carried out to the outside 1b. When the temporary scaffolds 31 and 32 are dismantled and the rolling scaffold 40 is assembled in this way, the safety of the internal environment of the chimney 1 has been confirmed in advance by the first internal air measurement process. Without sucking in, the worker M can enter the inside 1a and work efficiently while wearing normal work equipment.

  Next, as shown in FIG. 8, the hopper 4 is blown out in a spiral shape from the tube opening 4 a side using the rolling scaffold 40 (hopper disassembly step). When the hopper 4 is melted in this way, the hopper 4 melted in a belt shape hangs downward, and the hopper 4 is disassembled by sequentially melting and slicing the suspended belt-like hopper 4. At this time, since the worker M disassembles the hopper 4 with the equipment for normal work attached without sucking the internal air, the disassembly work of the hopper 4 can be performed efficiently. The chopped hopper 4 (hopper piece) is carried out to the outside 1b through the security room 33 and scrapped.

  Next, after disassembling the hopper 4, the temporary equipment is carried into the interior 1 a of the chimney 1 from the flue opening 2 and the passage opening 30, and as shown in FIG. The temporary scaffold 41 connected continuously is assembled. At this time, since the hopper 4 has been dismantled and removed in advance, the assembly work of the temporary scaffold 41 that reaches the rectifying plate portion 21 continuously from the lower portion 1d of the chimney 1 can be easily and suitably performed.

  Next, the closing member 39 is installed in the chimney opening 2 and the dust collecting hat 14 is installed in the top 1c of the chimney 1, and the internal dust collector 25 is driven to suck the internal air of the chimney 1 so that the inside 1a is removed. Use negative pressure. Then, the worker M wearing the work level 1 equipment for asbestos treatment has the heat insulating layer 9 covering the inner surface of the outer cylinder 5 of the rectifying plate portion 21, the surface 3 a of the rectifying plate 3, and the surface 6 a of the reinforcing beam 6. The coated heat insulating layers 7 and 8 are removed by spraying while spraying the dust scattering preventing agent (rectifying plate heat insulating layer removing step). At this time, since the heat-insulating layers 7, 8, and 9 can be removed using the temporary scaffold 41 that reaches the rectifying plate portion 21 continuously from the lower part 1d of the chimney 1, this removal work can be performed efficiently. Moreover, the heat insulation layers 7, 8, and 9 are removed from the suspension, and the hanging suspension that falls downward is packed in a bag, and is sequentially carried out from the security room 33 to the outside 1b by using a forklift. The hanger is treated as specially controlled industrial waste as described above. Then, at the stage where all of the heat insulating layers 7, 8, 9 of the rectifying plate portion 21 are suspended and removed, dust scattering inhibitors are sprayed on the outer cylinder 5, the rectifying plate 3 and the reinforcing beam 6 of the rectifying plate portion 21, respectively. The asbestos adhering to the outer cylinder 5, the current plate 3 and the reinforcing beam 6 is solidified.

  In this embodiment, after removing the heat insulation layers 7, 8, and 9 of the rectifying plate portion 21 in this way, the second measurement of the amount of asbestos dust (amount of harmful substances) in the internal air of the chimney 1 is performed (second) Internal air measurement process). Then, after confirming that the amount of asbestos dust in the internal air is a value that can release the separation of the chimney 1 by this second internal air measurement step, the driving of the internal dust collector 25 of the dust collection hat 14 is performed. And the dust collecting hat 14 is removed from the top 1c of the chimney 1 (outer cylinder 5). Further, the blocking member 39 blocking the flue opening 2 is removed. Further, the worker M enters the inside 1a, and the current plate 3 and the reinforcing beam 6 of the current plate portion 21 are sequentially separated from the outer cylinder 5 and disassembled and removed (rectifier plate dismantling process). In this way, the current plate 3 and the reinforcing beam 6 are disassembled, and the temporary scaffold 41 installed in the interior 1a of the chimney 1 is sequentially disassembled from above and removed. Further, the temporary scaffold 13 and the security room 33 installed on the outside 1b are disassembled and removed.

  And when dismantling and removing the current plate 3 and the reinforcing beam 6 from which the heat insulating layers 7 and 8 have been removed in this way, the safety of the internal environment of the chimney 1 has been confirmed in advance by the second internal air measurement step. Therefore, without sucking the internal air, the worker M can enter the inside 1a with normal work equipment and can work efficiently. Moreover, since the dismantling operation | work of the rectifying plate 3 and the reinforcement beam 6 can be performed using the temporary scaffold 41 which reaches | attains the rectifying plate part 21 continuously from the lower part 1d of the chimney 1, it can operate | work efficiently also from this point.

  Next, at the stage where the current plate 3 is disassembled, as shown in FIG. 10, an operator using the aerial work vehicle 42 is supported by hanging and supporting the top 1 c side of the chimney 1 (outer cylinder 5) with the crane 12. M cuts, separates, and disassembles the outer cylinder 5 of the rectifying plate portion 21 and the hopper portion 22 along the cutting line S (outer cylinder disassembly step). In this way, the disassembling work of the chimney 1 is completed by sequentially repeating the cutting / separating work from the top 1c side of the outer cylinder 5 (chimney 1). The dismantled rectifying plate 3, the reinforcing beam 6, and the outer cylinder block piece 43 are scrapped.

  Therefore, in the chimney disassembly method of this embodiment, in the chimney upper part disassembly process, the chimney upper part 20 is cut into a ring shape, the chimney block piece 11 is cut out and disassembled, and the chimney lower part (rectifying plate part 21 and hopper part 22). In the stage where the hopper part heat insulation layer removal process and the rectifying plate part heat insulation layer removal process, the hopper disassembly process and the rectification plate disassembly process are separated from the chimney lower part disassembly process, respectively, and the heat insulation layers 9 and 10 of the hopper part 22 are removed. The hopper 4 is disassembled, the heat insulating layers 7, 8, and 9 of the rectifying plate portion 21 are removed at the stage where the hopper 4 is disassembled, and the rectifying plate 3 and the heat insulating layers 7, 8, and 9 of the rectifying plate portion 21 are removed. The reinforcing beam 6 is disassembled.

  And when removing the heat insulation layers 7-10 of the hopper part 22 and the baffle plate part 21, respectively, the internal air of the chimney 1 was attracted | sucked, the inside 1a was made into negative pressure, and the equipment of the work level 1 of asbestos processing was equipped. By removing the heat insulating layers 7 to 10 by the worker M, it is possible to reliably prevent the asbestos from diffusing to the outside 1b and to remove the heat insulating layers 7 to 10.

  Moreover, after the hopper part heat insulation layer removal process, by measuring the amount of asbestos dust in the internal air in the first internal air measurement process and confirming that the interior 1a of the chimney 1 is not a harmful environment, the hopper dismantling process The hopper 4 can be disassembled by the worker M wearing normal work equipment without sucking the internal air, and the hopper 4 can be efficiently disassembled.

  Further, by disassembling the hopper 4 prior to the rectifying plate portion heat insulating layer removing step, in the rectifying plate portion heat insulating layer removing step, the temporary scaffold 41 is continuously provided from the lower part 1d of the chimney 1 to the hopper portion 22 and the rectifying plate portion 21. It becomes possible to install the temporary scaffold 41, and it becomes possible to remove the heat insulation layers 7, 8, and 9 of the baffle plate portion 21 efficiently and easily.

  In addition, after the rectifying plate portion heat insulating layer removing step, the amount of asbestos dust in the internal air is measured in the second internal air measuring step, and it is confirmed that the inside 1a of the chimney 1 is not a harmful environment, thereby dismantling the rectifying plate. In the process, the rectifying plate 3 and the reinforcing beam 6 can be disassembled by the worker M wearing normal work equipment without sucking the internal air. Furthermore, at this time, it becomes possible to dismantle the current plate 3 and the reinforcing beam 6 using the temporary scaffold 41 continuously installed on the hopper portion 22 and the current plate portion 21 from the lower part 1d of the chimney 1. Thereby, it becomes possible to efficiently dismantle the current plate 3 and the reinforcing beam 6.

  And since only the outer cylinder 5 remains by disassembling the baffle plate 3, the reinforcement beam 6, and the hopper 4 in this way, it becomes possible to disassemble the outer cylinder 5 easily at an outer cylinder disassembly process.

  In addition, by providing a security room installation step for forming a security room 33 connected to the inside 1a of the chimney 1 through the passage opening 30 by forming a passage opening 30 through the hopper portion 22, Through the opening 30 and the security room 33, the worker M can enter and leave the chimney 1 and the temporary equipment can be carried in and out. This makes it possible to clean the worker M and the temporary materials and equipment coming out of the inside 1a of the chimney 1 in the security room 33, and isolate the inside 1a of the chimney 1 from the outside 1b in the security room 33 ( The asbestos in the interior 1a of the chimney 1 can be reliably prevented from diffusing to the exterior 1b.

  Therefore, according to the chimney disassembly method of the present embodiment, the heat insulating layers 7 to 10 of the hopper portion 22 and the rectifying plate portion 21 are removed by being divided into a hopper portion insulating layer removing step and a rectifying plate portion insulating layer removing step, Prior to the rectifying plate heat insulating layer removing step and the rectifying plate disassembling step, the hopper 4 is disassembled in the hopper disassembling step, and further, the chimney 1 is divided into two in the first internal air measuring step and the second internal air measuring step. By checking the amount of asbestos dust in the internal air and disassembling the hopper 4, the rectifying plate 3 and the reinforcing beam 6 individually in the hopper disassembling step and the rectifying plate disassembling step while ensuring safety, the inside 1 a It is possible to efficiently disassemble the chimney lower portions 21 and 22 in which the rectifying plate 3, the reinforcing beam 6, and the hopper 4 are installed while preventing the diffusion of asbestos to the outside 1b.

  As mentioned above, although one Embodiment of the chimney disassembly method concerning this invention was described, this invention is not limited to said one Embodiment, In the range which does not deviate from the meaning, it can change suitably. For example, in the present embodiment, it is assumed that the harmful substance is asbestos, and the heat insulating layers 7 to 10 containing this asbestos are removed without scattering asbestos (dust), but the chimney of the present invention The dismantling method may be applied, for example, when disassembling the chimney 1 in which dioxins and other harmful substances such as plants and incinerators adhere to the heat insulating layers 7 to 10, and the same operation as in this embodiment. It is possible to efficiently dismantle the chimney 1 without reliably scattering these harmful substances to the outside 1b. Furthermore, the chimney disassembly method of the present invention may be applied to simply dismantle the chimney 1 simply by preventing the diffusion of dust (hazardous substances).

  Further, in the present embodiment, in the chimney upper part dismantling process, the chimney upper part 20 is cut and separated in a circular shape to cut and separate the chimney block piece 11, but in the chimney upper part dismantling process according to the present invention, the chimney upper part is disassembled. It is not necessary to limit 20 to cutting and separating 20 in a circular shape.

It is a figure which shows the state which has disassembled the chimney upper part of this chimney while showing the chimney disassembled with the chimney disassembly method which concerns on one Embodiment of this invention. It is a figure which shows the lower part (rectifier plate part and hopper part) of the chimney disassembled with the chimney disassembly method which concerns on one Embodiment of this invention. It is a figure which shows the state which has disassembled the chimney upper part in the chimney disassembly method which concerns on one Embodiment of this invention. In the chimney disassembly method according to one embodiment of the present invention, it is a diagram showing a state where a security room is installed while a passage opening is formed through the chimney lower part. It is a X1-X1 line arrow directional view of FIG. FIG. 5 is a view taken along line X2-X2 in FIG. 4. It is a figure which shows the state which removed the heat insulation layer of the hopper part in the chimney disassembly method which concerns on one Embodiment of this invention. It is a figure which shows the state which has disassembled the hopper in the chimney disassembly method which concerns on one Embodiment of this invention. It is a figure which shows the state which installed the temporary scaffold which reaches a hopper part and a baffle plate part continuously from the lower part of a chimney in the chimney disassembly method which concerns on one Embodiment of this invention. In the chimney disassembly method according to one embodiment of the present invention, after the heat insulation layer of the rectifying plate portion is removed and the rectifying plate and the reinforcing beam are dismantled and removed, the outer cylinder of the hopper portion and the rectifying plate portion is disassembled. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chimney 1a Inside 1b Outside 1c Top part 1d Lower part 2 Flue opening (flue entrance)
3 Current plate (steel plate)
3a Surface 4 Hopper 4a Tube port 4b Inner surface 5 Outer tube 6 Reinforcement beam 7 Heat insulation layer of reinforcement beam 8 Heat insulation layer of current plate 9 Heat insulation layer of outer tube (inner tube)
DESCRIPTION OF SYMBOLS 10 Heat insulation layer of hopper 11 Chimney block piece 12 Crane 13 Temporary scaffold 14 Dust collection hat 15 Chimney block piece processing yard 20 Chimney upper part 21 Current plate part 22 Hopper part 25 Internal dust collector 26 External dust collector 30 Passage opening 31 Temporary scaffolding 32 Temporary scaffolding 33 Security room 34 Outer shell 35 Inner shell 36 Front chamber 37 Washing chamber 38 Rear chamber 39 Closing member 40 Rolling scaffold 41 Temporary scaffolding 42 Aerial work block 43 Outer cylinder block piece M Worker O1 Axis line S Cutting line

Claims (2)

A heat insulating layer of the inner cylinder is arranged on the inner side in the radial direction of the outer cylinder, the surface is covered with the heat insulating layer, and a current plate for rectifying and discharging smoke introduced from the flue opening, A method of disassembling a chimney constructed by installing a hopper provided at the bottom and a hopper whose inner surface facing upward is covered with a heat insulating layer inside the lower side,
The chimney has a chimney upper part above the current plate, a part from the hopper to the lower part of the chimney is a hopper part, and a part between the chimney upper part and the hopper part is a current plate part. Has been
A chimney upper part dismantling step for dismantling the chimney upper part, and a chimney lower part dismantling step for dismantling the hopper part and the current plate part,
The chimney lower part dismantling step is a hopper part heat insulating layer removing step of removing the heat insulating layer of the hopper part in a state in which the air inside the chimney is sucked and the inside is made into a negative pressure,
A first internal air measurement step of measuring the amount of harmful substances in the internal air of the chimney after the hopper part heat insulation layer removal step;
A hopper dismantling step of disassembling the hopper after the first internal air measurement step;
After the hopper dismantling step, the rectifying plate portion heat insulating layer removing step of removing the heat insulating layer of the rectifying plate portion in a state in which the air inside the chimney is sucked and the inside is made negative pressure;
A second internal air measurement step of measuring the amount of harmful substances in the internal air of the chimney after the rectifying plate portion heat insulation layer removal step;
After the second internal air measurement step, a current plate dismantling step for dismantling the current plate,
A chimney disassembling method, comprising: an outer cylinder disassembling step of disassembling the outer cylinder of the rectifying plate portion and the hopper portion. The chimney dismantling method according to claim 1,
The chimney lower part disassembly step includes forming a passage opening in the hopper portion before the hopper portion heat insulation layer removing step, and connecting a security room connected to the inside of the chimney through the passage opening portion. A chimney dismantling method characterized by comprising a security room installation step to be installed outside the building.

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