Removal device

Abstract

To provide a removal device capable of efficiently performing a removal treatment on the inside of a plant constitution machine.SOLUTION: A removal device has a laser device and a reactive element, and removes a removal object existing on a metal surface in contact with combustion gas on the inside of a plant constitution machine constituting an electric power generation plant performing electric power generation by using combustion gas generated by combustion of fuel. The laser device emits laser light from a laser emission surface. The reaction element reflects the laser light emitted by the laser device. Here, the reactive element is installed so that the removal object is removed from the metal surface by irradiating the removal object with the laser light reflected by the reaction element.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a removing device.

Background Art

[0002] The metal surface of a metal member formed of a metal material may corrode due to the interaction between the metal material and the environment. For example, the metal surface may undergo a corrosion reaction such as oxidation due to a water film, moisture in the environment, oxygen in the air, etc., and corrosion products (rust, etc.) may be generated. Further, when there are corrosion components that induce corrosion, corrosion may occur significantly due to the adhesion of deposits composed of the corrosion components. Therefore, problems such as wall thickness reduction may occur in the metal member. As a result, with the progress of corrosion, there is a possibility that the strength of the metal member may decrease.

[0003] For example, in a metal member such as a heat transfer tube constituting a heat exchanger, the heat conduction performance may decrease due to corrosion products and deposits as corrosion progresses.

[0004] In order to prevent the occurrence of the above problems, it is necessary to perform a removal treatment with the corrosion products and deposits as the removal targets. Various techniques have been proposed as techniques related to the removal treatment. For example, techniques such as a removal treatment using a laser beam have been proposed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

[0006] [Non-Patent Document 1] Kazuyoshi Ogawa, et al., Investigation of Factors Contributing to Fatigue Strength Reduction in Hot-Rolled Steel Sheets Corroded with Saltwater, pp. 1211-1216, October 1985, The Materials Society of Japan, Materials, Vol. 34, No. 385 [Non-Patent Document 2] Tatsuro Sakamoto, et al., Basic study on the relationship between rust properties of carbon steel substrates before painting and coating durability, pp. 307-310, 2015, The Japan Society of Corrosion Engineering, Materials and Environment, Vol. 64. [Overview of the project] [Problems that the invention aims to solve]

[0007] However, with conventional techniques, it can be difficult to efficiently perform the removal process when the object to be removed has a complex shape.

[0008] For example, in the case of removal processing using laser light, the laser light has high coherence and propagates linearly through space. Therefore, the laser device cannot directly irradiate anything other than the object to be removed that is directly facing the metal surface from which the laser light is emitted. As a result, it is difficult to efficiently remove the object to be removed using laser light processing. When the laser device is larger than the aperture of the equipment containing the object to be removed, it is difficult to efficiently remove the entire object to be removed using laser light processing, and the above-mentioned problems occur.

[0009] In particular, the above-mentioned problems have become apparent when removing substances present on metal surfaces that come into contact with combustion gases inside plant components such as heat exchangers that make up power plants that recover heat from combustion gases produced by the burning of fuel to generate steam, which then drives a turbine to generate electricity.

[0010] Therefore, the problem to be solved by the present invention is to provide a removal device capable of efficiently performing a removal process inside a plant component device.

Means for Solving the Problem

[0011] The removal device of the embodiment includes a laser device and a reflection element, Coating area and and removes an object to be removed existing on a metal surface that comes into contact with combustion gas inside a plant component device that constitutes a power generation plant that generates power using combustion gas generated by combustion of fuel. The laser device emits laser light from a laser emission surface. The reflection element reflects the laser light emitted by the laser device The system is installed such that the reflected laser light is irradiated onto the object to be removed, thereby removing the object from the metal surface. . The coating section applies paint to the metal surface from which the object to be removed has been removed.

Effect of the Invention

[0012] According to the present invention, it is possible to provide a removal device capable of efficiently performing a removal process inside a plant component device.

Brief Description of the Drawings

[0013] [Figure 1] FIG. 1 is a diagram schematically showing a power generation plant 1 in the first embodiment. [Figure 2A] FIG. 2A is a diagram schematically showing a main part of a heat exchanger 6 (see FIG. 1) in the first embodiment. [Figure 2B] FIG. 2B is a diagram schematically showing a main part of a heat exchanger 6 (see FIG. 1) in the first embodiment. [Figure 3] FIG. 3 is a diagram schematically showing the removal device 80 of the first embodiment. [Figure 4A] FIG. 4A is a diagram schematically showing a removal process in the removal device 80 of the first embodiment. [Figure 4B] FIG. 4B is a diagram schematically showing a removal process in the removal device 80 of the first embodiment. [Figure 4C]FIG. 4C is a diagram schematically showing a removal process in the removal device 80 of the first embodiment. [Figure 5] FIG. 5 is a diagram schematically showing a modified example of the removal device 80 of the first embodiment. [Figure 6] FIG. 6 is a diagram schematically showing the removal device 80 of the second embodiment. [Figure 7] FIG. 7 is a diagram schematically showing a modified example of the removal device 80 of the second embodiment. [Figure 8] FIG. 8 is a diagram schematically showing the removal device 80 of the third embodiment. [Figure 9] FIG. 9 is a diagram schematically showing the removal device 80 of the fourth embodiment. [Figure 10] FIG. 10 is a diagram schematically showing the removal device 80 of the fifth embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0014] <First Embodiment> [A] Configuration of Power Generation Plant Before explaining the removal device 80 (see FIG. 3) of the embodiment, the power generation plant 1 including the object to be removed by the removal device 80 will be exemplified.

[0015] FIG. 1 is a diagram schematically showing the power generation plant 1 in the first embodiment.

[0016] As shown in FIG. 1, the power generation plant 1 of the present embodiment includes a gas turbine 2, a first generator 3, an exhaust duct 4, a waste heat recovery boiler 5 including a heat exchanger 6, a chimney 8, a water circulation line 9, a steam turbine 10, a second generator 11, and a condenser 12.

[0017] The power plant 1 of this embodiment is a thermal power plant that generates electricity using combustion gas G produced by the combustion of fuel (for example, fossil fuels such as natural gas, oil, and coal). Specifically, the power plant 1 of this embodiment is, for example, a combined cycle thermal power plant, in which internal combustion power generation is performed using a gas turbine 2 as an internal combustion engine, and steam power generation is performed using the waste heat. Note that the power plant 1 may be a system other than the combined cycle system.

[0018] In the power plant 1 of this embodiment, as described above, internal combustion power generation is performed by transmitting the rotational force of the gas turbine 2 to the first generator 3.

[0019] The combustion gas G discharged from the gas turbine 2 is sent to the heat recovery boiler 5 via the exhaust duct 4. In the heat recovery boiler 5, heat exchange takes place between water W and the combustion gas G in a heat exchanger 6 installed inside. As a result, the water W evaporates in the heat recovery boiler 5 and becomes steam S.

[0020] The combustion gas G that has passed through the heat recovery boiler 5 is sent to the chimney 8 via the exhaust duct 4. The combustion gas G is then discharged into the atmosphere from the chimney 8.

[0021] The steam S evaporated in the heat exchanger 6 is introduced to the steam turbine 10 via the water circulation line 9. This transmits the rotational force of the steam turbine 10 to the second generator 11, thereby generating electricity.

[0022] The steam that has passed through the steam turbine 10 is sent to the condenser 12, where it is condensed back into water W (condensed water). The water W condensed in the condenser 12 is returned to the waste heat recovery boiler 5 via the water circulation line 9.

[0023] [B] Configuration of heat exchanger 6 Figures 2A and 2B schematically show the main parts of the heat exchanger 6 (see Figure 1) in the first embodiment.

[0024] As shown in Figures 2A and 2B, the heat exchanger 6 comprises a plurality of heat transfer tubes 13. In Figure 2A, the tube axis direction (longitudinal direction) of the heat transfer tubes 13 is shown aligned with the plane of the paper, while in Figure 2B, the tube axis direction of the heat transfer tubes 13 is shown perpendicular to the plane of the paper.

[0025] Although not shown in Figures 2A and 2B, water W (see Figure 1) flowing through the water circulation line 9 passes through the heat transfer tube 13. At this time, heat exchange takes place between the water W flowing inside the heat transfer tube 13 and the combustion gas G flowing around the heat transfer tube 13. As a result, the water W flowing inside the heat transfer tube 13 evaporates and becomes steam S.

[0026] As shown in Figures 2A and 2B, heat exchange fins 14 are provided on the outer surface of the heat transfer tube 13 to improve the efficiency of heat exchange. The heat exchange fins 14 are, for example, wound around the outer surface of the heat transfer tube 13 and extend in a spiral shape. Alternatively, multiple heat exchange fins 14 may be installed on the outer surface of the heat transfer tube 13 so as to be aligned along the tube axis of the heat transfer tube 13. The spacing 15 between a pair of heat transfer tubes 13 and the spacing 16 between a pair of heat exchange fins 14 are narrow sections.

[0027] The heat transfer tubes 13 and heat exchange fins 14 are formed from a metallic material (e.g., carbon steel) that mainly contains iron. As described above, the heat transfer tubes 13 and heat exchange fins 14 include a metallic surface that comes into contact with the combustion gas G.

[0028] Although not shown in Figures 2A and 2B, metal surfaces can corrode due to prolonged use or the adhesion of substances contained in combustion gas G. As a result, corrosion products and deposits can accumulate on the metal surface, potentially reducing its thermal conductivity.

[0029] [C] Configuration of the removal device 80 A removal device 80 for performing a removal process on the above-mentioned corrosion products and deposits, which are treated as the target object 20, will be explained with reference to Figure 3.

[0030] Figure 3 is a schematic diagram showing the removal device 80 of the first embodiment. Figure 3 also shows the state of the removal device 80 when the removal process is performed on the object to be removed 20.

[0031] As shown in Figure 3, the removal device 80 of this embodiment is used to remove objects 20 that are present on metal surfaces in contact with combustion gas inside the plant components 70 that make up the power plant 1 (see Figure 1).

[0032] Here, we show a case where the plant component 70 includes a component 71, and the object to be removed 20 present on the metal surface of the component 71 is removed using a removal device 80. The plant component 70 is, for example, a waste heat recovery boiler 5 (see Figure 1), and the component 71 of the plant component 70 is a heat transfer tube 13 (see Figure 1) that constitutes a heat exchanger 6 in the waste heat recovery boiler 5.

[0033] As shown in Figure 3, the removal device 80 of this embodiment comprises a laser device 81 and a reflecting element 82. The various parts constituting the removal device 80 will now be described.

[0034] [C-1] Laser device 81 As shown in Figure 3, the laser device 81 includes a laser oscillator 811, a waveguide device L81, and a laser emission unit 812, and is configured to emit laser light L from the laser emission surface S81.

[0035] In the laser device 81, the laser oscillator 811 is a light source for laser light L. The waveguide device L81 includes, for example, an optical fiber and guides the laser light L emitted from the laser oscillator 811 to the laser emission unit 812. The laser emission unit 812 includes a laser emission surface S81 and is configured such that the laser light L emitted from the laser oscillator 811 is emitted from the laser emission surface S81 to the outside of the laser device 81 via the waveguide device L81.

[0036] Here, the laser device 81 emits laser light L having energy to vaporize the object to be removed 20. The laser light L may be either a pulsed wave or a continuous wave.

[0037] [C-2] Reflecting element 82 The reflective element 82 is, for example, a mirror, and is configured to reflect the laser light L emitted by the laser device 81, as shown in Figure 3.

[0038] When the removal process is performed on the object to be removed 20, the reflecting element 82 is positioned so that the object to be removed 20 is removed from the metal surface of the component 71 by the laser light L reflected by the reflecting element 82 irradiating the object to be removed 20.

[0039] In this embodiment, the reflecting element 82 is a plane mirror, and the plane mirror is installed inside the plant component 70. The reflecting element 82 reflects the laser light L emitted from the laser device 81 and entering the plant component 70 through an opening, changing the direction of the laser light L. As a result, the laser light L reflected by the reflecting element 82 is incident on the object to be removed 20, causing the object to be removed to evaporate.

[0040] The reflective element 82 is smaller than the opening of the plant component 70 and is installed inside through the opening of the plant component 70.

[0041] [D] Removal process method In this embodiment, when performing a removal process to remove the object to be removed 20 using the removal device 80, first, a reflective element 82 is installed inside the plant component equipment 70. Here, as shown in Figure 3, for example, the reflective element 82 is installed when removing the object to be removed 20 that is located on a metal surface other than the metal surface directly facing the laser emission surface S81 of the laser device 81. The installation of the reflective element 82 is performed, for example, by the worker performing the removal process checking the condition inside the plant component equipment 70. Alternatively, if necessary, the laser emission surface S81 of the laser device 81 and the reflective element 82 are connected and integrated with a rod or plate-shaped connecting part, and then inserted inside to perform the installation.

[0042] Subsequently, the laser device 81 emits laser light L, and the laser light L reflected by the reflecting element 82 is irradiated onto the object to be removed 20. As a result, the object to be removed 20 is removed.

[0043] Figures 4A to 4C schematically show the removal process in the removal device 80 of the first embodiment.

[0044] Figures 4A to 4C show cross-sections of components 71 (for example, heat transfer tubes 13 of a heat exchanger 6; see Figure 2A) on which the object to be removed 20 is located on the metal surface, and the removal process for removing the object to be removed 20 is shown in order from Figure 4A to Figure 4C.

[0045] As shown in Figure 4A, there are substances to be removed 20 on the metal surface of component 71. The substances to be removed 20 are corrosion products 18 and deposits 19. The corrosion products 18 are substances produced when the material of component 71 (e.g., carbon steel) is corroded by the combustion gas G. The deposits 19 are substances to which components contained in the combustion gas G have adhered, and include substances such as ammonium sulfate.

[0046] As shown in Figure 4B, the laser beam L is irradiated onto the object to be removed 20. In this embodiment, in the removal device 80, the laser beam L emitted from the laser device 81 is reflected by the reflecting element 82 before being incident on the object to be removed 20.

[0047] As a result, as shown in Figure 4C, which shows an enlarged view of the object to be removed 20 in Figure 4B and simplifies it to the form shown in Figure 4A, in this embodiment, the object to be removed 20 is decomposed by the laser into decomposition products 21 such as evaporated corrosion products, corrosion components, and trace amounts of rust scattered by impact.

[0048] Here, the removal process is performed using laser light L having a wavelength corresponding to the characteristic absorption wavelength of the object to be removed 20, thereby enabling selective and efficient removal of the object to be removed 20. In other words, the removal process is performed using the laser ablation effect, which is the interaction between light and matter. In order to obtain a sufficient laser ablation effect, factors such as the absorption characteristics of the compounds constituting the object to be removed 20, the density of the object to be removed 20, the thickness of the object to be removed 20, the laser oscillation wavelength of the laser light L, and the laser power density of the laser light L are taken into consideration.

[0049] By irradiating the object to be removed 20 with laser light L having an energy density above a certain level, the object to be removed 20 absorbs the light energy of the laser light L and instantaneously heats up. As a result, the object to be removed 20 becomes plasma and sublimes as decomposition products 21. Although the plasma-generated material may recombine and produce re-products, the particle size is small, so it is unlikely to cause a decrease in the function of the component parts 71 and is unlikely to generate visible dust.

[0050] [E] Summary As described above, the removal device 80 of this embodiment comprises a laser device 81 and a reflecting element 82 that reflects the laser light L emitted by the laser device 81. The removal device 80 is installed inside the plant component equipment 70 such that the laser light L reflected by the reflecting element 82 is irradiated onto the object to be removed 20, thereby removing the object to be removed 20 from its metal surface.

[0051] Therefore, in this embodiment, the laser beam L can be irradiated with the object to be removed 20 on metal surfaces other than the metal surface directly facing the laser emission surface S81 of the component 71 using the reflecting element 82. As a result, in this embodiment, the object to be removed 20 can be efficiently removed by the removal process using the laser beam L.

[0052] Furthermore, the metal surface from which the object to be removed 20 has been removed is covered with a coating layer, for example, by applying paint. In this case, since the object to be removed 20 is not interposed between the metal surface and the coating layer, it is possible to suppress the peeling of the coating layer from the metal surface. The coating may be performed after the metal surface has been roughened.

[0053] [F] Variation A modified example of the above embodiment will be described.

[0054] Figure 5 is a schematic diagram showing a modified removal device 80 of the first embodiment. Similar to Figure 3, Figure 5 also shows the state of the removal device 80 when the removal process is performed on the object to be removed 20.

[0055] As shown in Figure 5, the removal device 80 may be equipped with a plurality of reflective elements 82, and the plurality of reflective elements 82 may be installed inside the plant component equipment 70. The laser beam L may then be reflected sequentially by the plurality of reflective elements 82, thereby irradiating the object to be removed 20 with the laser beam L.

[0056] <Second Embodiment> [A] Configuration of the removal device 80 Figure 6 is a schematic diagram showing the removal device 80 of the second embodiment. Similar to Figure 3, Figure 6 also shows the state of the removal device 80 when the removal process is performed on the object to be removed 20.

[0057] As shown in Figure 6, the shape of the reflective element 82 in the removal device 80 of this embodiment differs from that of the first embodiment (see Figure 3). Except for this point and related points, this embodiment is the same as the first embodiment. For this reason, redundant components are denoted by the same reference numerals and their descriptions are omitted as appropriate.

[0058] In the removal device 80 of this embodiment, the reflective element 82 is a concave mirror, not a plane mirror, as shown in Figure 6.

[0059] Here, the concave mirror reflecting element 82 is installed inside the plant equipment 70 so that the focal point of the reflected laser beam L is located outside the object to be removed 20. In this embodiment, the reflecting element 82 is installed so that the focal point of the reflected laser beam L is located inside the component 71 that makes up the plant equipment 70. For example, the reflecting element 82 is installed so that the focal point of the laser beam L coincides with the central axis of a component 71 that has a cylindrical outer shape. Alternatively, the focal point of the reflected laser beam L may be located on the object to be removed 20.

[0060] [B] Summary As described above, in the removal device 80 of this embodiment, the reflective element 82, which is a concave mirror, is installed inside the plant component equipment 70 such that the focal point of the reflected laser light L is located outside the object to be removed 20. Therefore, as can be seen from Figure 6, even if the position of the emission surface S81 or the angle of incidence of light to the reflective element 82 changes, the laser light L is reliably irradiated onto the surface of the component 71. As a result, the emission surface S81 can be installed over a wider area than when a plane mirror is used, and the object to be removed 20 is removed from the metal surface.

[0061] Therefore, in this embodiment, the removal of the object to be removed 20 can be carried out with reduced labor.

[0062] [C] Variant A modified example of the above embodiment will be described.

[0063] Figure 7 is a schematic diagram showing a modified removal device 80 of the second embodiment. Similar to Figure 6, Figure 7 also shows the state of the removal device 80 when the removal process is performed on the object to be removed 20.

[0064] As shown in Figure 7, the reflective element 82 constituting the removal device 80 may be a convex mirror instead of a concave mirror.

[0065] In this case as well, the laser beam L is irradiated over a wide area of ​​the object to be removed 20, similar to the embodiment described above. As a result, more of the object to be removed 20 is removed from the metal surface than when the focal point of the laser beam L coincides with the object to be removed 20.

[0066] Therefore, in this modified example as well, the removal of the object to be removed 20 can be carried out efficiently.

[0067] <Third Embodiment> [A] Configuration of the removal device 80 Figure 8 is a schematic diagram showing the removal device 80 of the third embodiment. Similar to Figure 3, Figure 8 also shows the state of the removal device 80 when the removal process is performed on the object to be removed 20.

[0068] As shown in Figure 8, the removal device 80 of this embodiment differs from that of the first embodiment (see Figure 3) in that it includes a reflection angle changing unit 83. Except for this point and related points, this embodiment is the same as the first embodiment. Therefore, explanations of redundant matters will be omitted as appropriate.

[0069] In the removal device 80 of this embodiment, the reflection angle changing unit 83 is as shown in Figure 8, It is installed on the reflecting element 82 and is configured to change the angle at which the reflecting element 82 reflects the laser light L.

[0070] The reflection angle changing unit 83, for example, rotatably supports the reflecting element 82 and is configured to change the orientation of the reflective surface of the reflecting element 82 by driving a motor. In addition, the reflecting element 82 may be configured to change the angle at which it reflects the laser beam L by various means, such as deforming the reflective surface of the reflecting element 82 using a piezoelectric element.

[0071] [B] Summary As described above, in the removal device 80 of this embodiment, the angle at which the reflective element 82 reflects the laser beam L is changed by the reflection angle changing unit 83. Therefore, as can be seen from Figure 8, the laser beam L is irradiated over a wide area of ​​the object to be removed 20.

[0072] Therefore, in this embodiment, the removal of the object to be removed 20 can be carried out efficiently.

[0073] <Fourth Embodiment> [A] Configuration of the removal device 80 Figure 9 is a schematic diagram showing the removal device 80 of the fourth embodiment. Similar to Figure 3, Figure 9 also shows the state of the removal device 80 when the removal process is performed on the object to be removed 20.

[0074] As shown in Figure 9, the removal device 80 of this embodiment differs from that of the first embodiment (see Figure 3) in that it includes a reflective element moving unit 84. Except for this point and related points, this embodiment is the same as the first embodiment. Therefore, explanations of redundant matters will be omitted as appropriate.

[0075] In the removal device 80 of this embodiment, the reflective element moving unit 84 is configured to move the reflective element 82 inside the plant component equipment 70, as shown in Figure 9.

[0076] Here, the reflective element moving section 84 includes, for example, a rail 841 and a wire 842. The rail 841 is, for example, linear and guides the reflective element 82 to move linearly. The wire 842 is attached to the reflective element 82. For example, an operator can move the reflective element 82 along the rail 841 by manipulating the wire 842. Alternatively, the reflective element 82 may be configured to move by various driving means such as a motor. Furthermore, although this example shows the rail 841 installed in the left-right direction (horizontal direction with respect to the plane of the paper), it may also be installed in the up-down direction (perpendicular direction with respect to the plane of the paper) or along the long axis of the component 71 (from back to front with respect to the plane of the paper).

[0077] [B] Summary As described above, in the removal device 80 of this embodiment, the position of the reflecting element 82 relative to the object to be removed 20 is changed by the reflecting element moving unit 84. Therefore, as can be seen from Figure 9, the laser beam L is irradiated over a wide area of ​​the object to be removed 20.

[0078] Therefore, in this embodiment, the removal of the object to be removed 20 can be carried out efficiently.

[0079] <Fifth Embodiment> [A] Configuration of the removal device 80 Figure 10 is a schematic diagram showing the removal device 80 of the fifth embodiment. Figure 10 also shows the state of the removal device 80 after the removal process has been performed on the object to be removed 20.

[0080] As shown in Figure 10, the removal device 80 of this embodiment differs from that of the first embodiment (see Figure 3) in that it includes an application section 86. Except for this point and related points, this embodiment is the same as the first embodiment. Therefore, explanations of redundant matters will be omitted as appropriate.

[0081] In this embodiment, after the object to be removed 20 is removed, the metal surface is roughened by the continued irradiation of the laser light L by the removal device 80 (see, for example, Figure 3), resulting in the surface of the component 71 being roughened.

[0082] The coating unit 86 is installed inside the plant equipment 70 to apply paint to the metal surface that has been roughened as described above. Specifically, the coating unit 86 includes a painting apparatus that includes a paint nozzle.

[0083] [B] Summary As described above, the removal device 80 of this embodiment includes an application section 86.

[0084] In this embodiment, the metal surface from which the object to be removed 20 has been removed is roughened and then coated. In this case, since the object to be removed 20 is not interposed between the metal surface and the coating layer, it is possible to suppress the peeling of the coating layer from the metal surface.

[0085] <Other> It should be noted that the present invention is not limited to the embodiments described above, and can be implemented in various forms other than those described above during the implementation phase. The present invention can be omitted, added, replaced, or modified in various ways without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0086] 1: Power plant, 2: Gas turbine, 3: First generator, 4: Exhaust duct, 5: Waste heat recovery boiler, 6: Heat exchanger, 8: Chimney, 9: Water circulation line, 10: Steam turbine, 11: Second generator, 12: Condenser, 13: Heat transfer tube, 14: Heat exchange fin, 15: Spacing, 16: Spacing, 18: Corrosion products, 19: Adhesion, 20: Object to be removed, 21: Decomposition products, 70: Plant components, 71: Components, 80: Removal device, 81: Laser device, 82: Reflecting element, 83: Reflection angle changing section, 84: Reflecting element moving section, 86: Coating section, 811: Laser oscillator, 812: Laser emission section, 841: Rail, 842: Wire, G: Combustion gas, L: Laser light, L81: Waveguide device, S81: Laser emission surface, W: Water, S: Steam

Claims

1. A removal device for removing objects present on metal surfaces that come into contact with combustion gases inside a power plant that generates electricity using combustion gases produced by the combustion of fuel, A laser device that emits laser light from a laser emission surface, A reflective element is installed such that the laser beam emitted by the laser device is reflected, and the reflected laser beam is irradiated onto the object to be removed, thereby removing the object from the metal surface. The coating section applies paint to the metal surface from which the object to be removed has been removed. Equipped with, removal device.

2. The plant equipment in the power plant is a heat recovery boiler, wherein at least one of the components constituting the heat recovery boiler includes the metal surface. The removal device according to claim 1.

3. The aforementioned components are parts that constitute a heat exchanger in the heat recovery boiler. The removal device according to claim 2.

4. The reflective element includes a plane mirror, and the plane mirror is installed inside the plant equipment. The removal device according to claim 1.

5. The laser light has energy to vaporize the object to be removed. The removal device according to claim 1.

6. The removal device according to claim 5, wherein the reflective element is installed so that the focal point of the laser beam is located outside the object to be removed.

7. The reflective element includes a concave mirror, and the concave mirror is installed inside the plant equipment. A removal device according to any one of claims 1 to 3 and claim 6.

8. The reflective element includes a convex mirror, and the convex mirror is installed inside the plant equipment. A removal device according to any one of claims 1 to 3 and claim 6.

9. A reflection angle changing unit is installed on the reflective element and configured to change the angle at which the reflective element reflects the laser light. Having, The removal device according to claim 1.

10. A reflective element moving unit configured to move the reflective element inside the plant equipment. Having, The removal device according to claim 1.

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