JPH06337102A - Structure for suspending and reinforcing main body in hexagonal pressure fluidized bed boiler - Google Patents

Abstract

PURPOSE:To provide a structure for suspending the main body of a hexagonal pressure fluidized bed boiler capable of equalizing load acting on the protruding parts of support beams and decreasing stress produced in a pressure container. CONSTITUTION:A main boiler body 1 housed in a pressure container 4 and support beams 9 for suspending the main boiler body are provided. The main 1 boiler body is composed of three rhombic posts 1a, 1b and 1c which are adjacent to one another. The support beam is respectively composed of a tee part 9a and a hexagonal part 9b. The outer ends of the tee parts are connected to three alternate top parts A of six tops A of a hexagonal part. The hexagonal part respectively comprises two protruding parts 30 extending along the sides of the hexagon from the three top parts A to which the tee parts are connected and a protruding part 31 extending along one end of the side of the hexagon from three top parts B to which the tee parts are not connected. The outer ends of the protruding parts are supported on the inner surface of the pressure container.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hexagonal pressure fluidized bed boiler, and more particularly to a main body suspension structure and a main body reinforcement structure for a hexagonal pressurized fluidized bed boiler.

[0002]

2. Description of the Related Art A pressurized fluidized bed combuster for fluidized combustion of coal under pressure is
The combined cycle combined with a gas turbine has a thermal efficiency of 40% or more, a high in-furnace desulfurization rate, and NO
Since it has features such as a small amount of x generation, it is currently being developed as a new type boiler that replaces the conventional fine powder boiler. Such a pressurized fluidized bed boiler is shown in FIG.
As shown in, the boiler main body 1, the cyclone 2, the bed material storage container 3, etc. are configured to be stored in the pressure container 4, and the coal C supplied from the outside is burned in the boiler main body 1, The exhaust gas is sent to the cyclone 2, and the exhaust gas from which ash has been removed by the cyclone 2 is supplied to an external gas turbine (not shown) for work (for example, driving a generator). Further, in the boiler body 1, a fluidized bed B in which bed material such as coal ash or sand is fluidized by the air A supplied from below is formed. In the fluidized bed B, steam is generated. The evaporator 5, the superheater 6, and the reheater 7 are inserted. Due to the heat generated by the combustion of coal in the fluidized bed B, water is evaporated in the evaporator 5 to become steam, and the steam is further heated in the superheater 6 to become superheated steam, which is provided outside. The steam turbine (not shown) expands and does work. Further, the steam whose temperature has dropped in the steam turbine is reheated in the reheater 7 to become superheated steam, and the work is performed again in the external steam turbine. FIG. 5 is an overall configuration diagram of a hexagonal pressurized fluidized bed boiler (hereinafter, referred to as a hexagonal fluidized bed boiler) in which the boiler body 1 is in the form of a hexagonal column. In this figure,
The hexagonal fluidized bed boiler has a configuration in which the boiler body 1, the cyclone 2, the bed material storage container 3, and the like are housed in the pressure container 4 as in FIG. 8, and coal supplied from the outside is supplied to the boiler body. 1, the exhaust gas is sent to a cyclone 2 via an exhaust gas manifold, and the exhaust gas from which ash has been removed by the cyclone 2 is supplied to an external gas turbine (not shown) to do work. . Figure 6
It is a perspective view showing the boiler body circumference of a hexagonal fluidized bed boiler, and consists of a hexagonal-pillar boiler body 1, its bottom 10, and a support beam 9 for suspending the boiler body 1. The boiler body 1 and its bottom 10 are shown separately for clarity. The boiler body 1 has three rhombus columns 1a, 1b, and 1c adjacent to each other, there is no partition inside, each surface of the hexagonal column is a water pipe wall, and each corner of the hexagonal column is a header. Has been done. There are rhomboid openings on the upper surfaces of the three rhomboid columns 1a, 1b, and 1c, and the inner layer tube can be taken out from these openings. The bottom 10 of the boiler body 1 is composed of a steam header 8 composed of a hexagon and a trifurcation, and an ash chute 11, and a bed material containing ash can be taken out from the lower surface of the steam header 8 through the ash chute 11. You can do it. Further, two steam headers 20 (Cold Reheat Pipes) for low-temperature reheat steam are arranged on the bottom portion 10 of the boiler body 1 so as to correspond to the three rhombus columns 1a, 1b, and 1c, respectively. (Only shown for rhomboid 1a in the figure). FIG. 7 is a horizontal sectional view taken along the line AA of FIG. In this figure, the boiler body 1 has a hexagonal interior in horizontal section, and has six vertical water pipe walls 12a, 12b.
And a hexagonal closed back stay 14. The inside of the hexagon is 3 degrees apart from the center by 120 °.
It is divided into three spaces by the virtual dashed-dotted line of the book. That is, the inside of the hexagon has two adjacent water tube walls 12a, 1
A horizontal section having 2b as two sides of the parallelogram is composed of three spaces of the parallelogram. In each space, one water pipe wall 1
2a, a first layer inner tube group 16a having one end adjacent to the other water tube wall 12b and having vertical planes parallel to each other, and one water tube wall 12a and the first layer Inner tube group 1
The second end of which one end is adjacent to the other end of 6a and whose vertical planes are parallel to each other
And the inner layer tube group 16b.

[0003]

As shown in FIG. 6, the boiler body 1 is suspended by a support beam 9 so that it can be freely expanded downward. Therefore, a large load (for example, about 1200 tons), which is the total weight of the boiler body 1 and the bed material (fluid medium) inside the boiler body 1, acts on the support beam 9. Further, the support beam 9 includes three rhombus pillars 1a, 1b, 1c.
Since the inner in-layer tube is taken out from the rhombus opening on the upper surface of, the beam cannot be provided above the rhombus opening. for that reason,
The support beam 9 has a three-pronged portion 9a and a hexagonal portion 9 as shown.
The weight of about half of the total weight acts on the three-pronged portion 9a. That is, about 1/4 of the total weight (about 300 tons) acts on each of the vertices A connected to the three-pronged portion 9a, and about 1/12 of the total weight on each of the vertices B that are not connected to the three-forked portion 9a ( It was found that only about 100 tons) worked. Therefore, as shown in FIG.
If bulges are provided on both sides of three sides and the bulges are supported by the inner surface of the pressure vessel, the loads received at the vertices A and B are non-uniform, and the bulges from the vertex A are supported. There has been a problem that excessive stress is partially generated in the pressure vessel. The first invention of the present invention was devised to solve such a problem. That is, an object of the first invention of the present invention is to provide a main body suspension structure for a hexagonal pressurized fluidized bed boiler, which can make the load acting on the overhanging portion of the support beam uniform and reduce the stress generated in the pressure vessel. To provide.

In the above-mentioned hexagonal fluidized bed boiler, the pressure inside the pressure vessel is high (for example, 10 ata), and the differential pressure between the inside and outside of the boiler body 1 is 6000 mmAq to 7000 m.
It reaches mAq, and an external pressure of 6 to 7 ton / m ² acts on the boiler body. As shown in FIG. 7, the inner-layer tube groups 16a and 16b are densely arranged inside the boiler main body 1,
Since these are connected by a connecting member (not shown), external pressure can be received. However, as shown in FIG.
The bottom portion 10 of the boiler main body 1 is composed of a steam header 8 composed of a hexagon and a trifurcation, and an ash chute 11, and one side F of the three parallelogram parts surrounded by the steam header 8 is formed.
A plurality of connecting steam pipes 22 are arranged in parallel with. Therefore, the steam header 8 (indicated by F in the figure) that is not connected by the connection steam pipe 22 bends inward when an external pressure is applied, which causes a large stress. The second invention of the present invention was devised to solve such a problem. That is, a second object of the present invention is to provide a main body reinforcing structure in which a large amount of flexure or stress does not occur in the steam header at the bottom of the boiler main body even when an external pressure due to a differential pressure is applied.

[0005]

According to the present invention, there is provided a boiler body which is housed in a pressure vessel and forms a fluidized bed therein,
And a support beam for suspending the boiler body, wherein the boiler body is composed of three rhombus columns adjacent to each other, and the support beam is a radius from a center of the pressure vessel along a top boundary line of the three rhombus columns. And a hexagonal portion aligned with the hexagonal upper surface of the boiler body, and an outer end of the trifurcated portion is formed by every other three of the six vertices of the hexagonal portion. Is connected to one vertex A,
The hexagonal portion further includes two overhanging portions extending from the three vertices A to which the three-forked portions are connected along the sides of the hexagon, and three vertices B not connected to the three-forked portions to one of the sides of the hexagonal portion. There is provided one overhanging portion extending along the outer end of the overhanging portion, and the outer end of the overhanging portion is supported on the inner surface of the pressure vessel. It

Further, according to the present invention, there is provided a steam header provided on the lower surface of the boiler main body housed in the pressure vessel, and an ash chute extending below the steam header and constituted by a water pipe wall, The boiler body includes three diamond-shaped pillars adjacent to each other, and the steam header includes a three-pronged portion extending in three radial directions from a center of the pressure vessel along a lower surface boundary line of the three diamond-shaped pillars, and the boiler body. Of the hexagonal lower surface and the matching hexagonal portion, and the three three-sided portions E and every other three sides E of the six sides of the hexagonal portion are
The side F that is connected by a plurality of connecting steam pipes parallel to the remaining side F and is not connected by the connecting steam pipe and the outermost connecting steam pipe are a plurality of parallel and spaced from the side E of the hexagonal portion. A structure for reinforcing a main body of a hexagonal pressurized fluidized bed boiler is provided, which is connected by a supporting steam pipe.

[0007]

According to the first structure of the present invention, the support beam for suspending the boiler body is composed of the trifurcated portion and the hexagonal portion, and the outer end of the trifurcated portion is one of the six apexes of the hexagonal portion.
Connected to every other three vertices A, and the hexagonal part is
Two overhanging parts extending from the three vertices A to which the three-pronged parts are connected along the hexagonal side, and three vertices B not connected to the three-forking part from one apex side to the one side of the hexagonal 1
Since the outer end of the overhanging portion is supported by the inner surface of the pressure vessel, even if about half the total weight of the overhanging portion acts on the trifurcating portion, the apex A connecting to the overhanging portion Only about 1/8 of the total weight (about 150 tons) acts on each. Therefore, the load is about 1/12 (about 100 tons) of the total weight acting on the apex B not connected to the three-pronged portion, the loads received on the apex A and the apex B are equalized, and the protruding portion from the apex A is extended. It is possible to reduce the partial stress generated in the pressure vessel 4 supporting the.

Further, according to the second aspect of the present invention, the steam header on the lower surface of the boiler is composed of the trifurcated portion and the hexagonal portion, and every three sides out of the six sides of the trifurcated portion and the hexagonal portion. One side E is connected by a plurality of connecting steam pipes parallel to the remaining side F, and the side F not connected by the connecting steam pipes and the outermost connecting steam pipe are parallel to the side E of the hexagonal portion and Since the supporting steam pipes are connected by a plurality of supporting steam pipes spaced apart from each other, the rigidity of the supporting steam pipes and the steam header of the side F connected to the connecting steam pipes is high, and it is difficult to bend even when receiving external pressure, and the generated stress is also high. Get smaller.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. In addition, in each figure, the same parts are denoted by the same reference numerals. 5 and 7 described above,
The same applies to the connection structure between the header and the steam pipe in the pressurized fluidized bed boiler according to the present invention, and the description thereof will be omitted here to avoid duplication. 1 is a perspective view similar to FIG. 6 showing a main body suspending structure and a main body reinforcing structure of a hexagonal pressurized fluidized bed boiler according to the present invention, and FIG. 2 is a plan view of FIG. 1 and 2, a hexagonal pressurized fluidized bed boiler main body suspension structure according to the present invention includes a boiler main body 1 which is housed in a pressure vessel 4 and forms a fluidized bed therein, and the boiler main body 1 is suspended. Boiler body 1 including support beam 9
Is composed of three rhombus columns 1a, 1b, 1c adjacent to each other. In addition, the support beam 9 includes three rhombus pillars 1a, 1b, 1
A three-pronged portion 9a extending in the three radial directions from the center of the pressure vessel 4 along the upper boundary line of c and a hexagonal portion 9b aligned with the hexagonal upper surface of the boiler body 1 are provided. The ends are connected to every other three vertices A of the six vertices of the hexagonal portion 9b. Hexagonal part 9b
Is further extended from the three vertices A to which the three-pronged portion 9a is connected along the hexagonal side, and the three vertices B from which the three-pronged portion 9a is not connected to one side of the hexagonal side. Having one overhanging portion 31 extending
The outer ends of the overhang portions 30 and 31 are supported on the inner surface of the pressure vessel 4. With this structure, even if about half of the total weight acts on the three-pronged portion, the vertex A connecting to the three-pronged portion is connected.
Only about 1/8 of the total weight (about 150 tons) acts on each of the. Therefore, the load is about 1/12 of the total weight (about 100 tons) that acts on the vertex B that is not connected to the three-pronged portion, and the loads received by the vertex A and the vertex B are made uniform,
It is possible to reduce the stress generated in the portion of the pressure vessel 4 that supports the protruding portion from the apex A.

FIG. 3 is an enlarged perspective view of portion C in FIG. In this figure, the outer end of the overhanging portion 30 is placed on the upper surface of a horizontal support member 32, and hanging metal fittings 33 are provided at both ends of the supporting member 32. Is connected to the lower end of the hanging member 35, and the upper end of the hanging member 35 is pivotally attached to the inner surface of the pressure vessel 4 by another horizontal pin 36. The support structure of the overhanging portion 31 is similar. With this configuration, the support beam 9 can be moved in the radial direction and the circumferential direction, and the downward load acting on the support beam 9 can be smoothly transmitted to the pressure vessel 4.

FIG. 4 is a side sectional view taken along the line DD of FIG. 1 and 4, a hexagonal pressurized fluidized bed boiler main body reinforcing structure according to the present invention includes a steam header 8 provided on a lower surface of a boiler main body 1 housed in a pressure vessel.
And an ash chute 11 that extends downward from the steam header 8 and is formed of a water pipe wall. Further, the boiler body is composed of three diamond-shaped columns 1a, 1b, 1c adjacent to each other. Furthermore, according to the invention, the steam header 8 comprises three rhombus pillars 1.
a, 1b, 1c, a trifurcated portion 8a extending in the three radial directions from the center of the pressure vessel along the lower boundary line, and a hexagonal portion 8b aligned with the hexagonal lower surface of the boiler body 1. 1 out of 6 sides of 8a and hexagonal part 8b
The three alternate sides E are connected by a plurality of connecting steam pipes 22 parallel to the remaining side F, and the side F not connected by the connecting steam pipes 22 and the outermost connecting steam pipe 22 are the hexagonal portion 8b. A plurality of supporting steam pipes 24 parallel to the side E and spaced apart from each other.
Are connected by. With this configuration, the rigidity of the steam header 8b on the side F connected to the supporting steam pipe 24 and the connecting steam pipe 22 is increased, and it is difficult for the steam header 8b to bend even when an external pressure is applied, and the generated stress is small.

[0012]

As described above, according to the first configuration of the present invention, the loads received at the vertices A and B are made uniform,
It is possible to reduce the stress generated in the portion of the pressure vessel 4 that supports the protruding portion from the apex A. In addition, according to the second configuration, the rigidity of the steam header 8b is increased, it is difficult for the steam header 8b to be bent even under external pressure, and the generated stress is also reduced. Therefore, the main body suspension structure and the main body reinforcement structure of the hexagonal pressurized fluidized bed boiler according to the present invention can make the load acting on the overhanging portion of the support beam uniform and reduce the stress generated in the portion of the pressure vessel, Moreover, even if an external pressure due to the differential pressure is applied, the steam header at the bottom of the boiler body is not largely bent or stressed,
Has excellent effect.

[Brief description of drawings]

FIG. 1 is a perspective view showing the periphery of a boiler body of a hexagonal fluidized bed boiler according to the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is an enlarged perspective view of a C portion of FIG.

FIG. 4 is a side sectional view taken along the line DD of FIG.

FIG. 5 is an overall configuration diagram of a hexagonal pressurized fluidized bed boiler.

FIG. 6 is a perspective view showing the vicinity of a boiler body of a hexagonal fluidized bed boiler.

FIG. 7 is a horizontal sectional view taken along the line AA in FIG.

FIG. 8 is an overall configuration diagram of a conventional pressurized fluidized bed boiler.

[Explanation of symbols]

 1 Boiler main body 2 Cyclone 3 Bed material storage container 4 Pressure vessel 5 Evaporator 6 Superheater 7 Reheater 8 Steam header 8a Three-pronged part 8b Hexagonal part 9 Support beam 9a Three-pronged part 9b Hexagonal part 10 Bottom part of boiler main body 11 Ash Chute 12a, 12b Water pipe wall 16a, 16b Layer inner pipe group 18 Steam header 20 Steam header for low temperature reheat steam 22 Connection steam pipe 24 Support steam pipe 30, 31 Overhanging part 32 Support member 33 Suspension fitting 34, 36 pin 35 Hanging member A Air B Fluidized bed C Coal

Claims (2)

[Claims] 1. A boiler main body which is housed in a pressure vessel and forms a fluidized bed inside thereof, and a support beam for suspending the boiler main body, wherein the boiler main body is composed of three diamond-shaped pillars adjacent to each other, The support beam includes a three-pronged portion extending in three radial directions from the center of the pressure vessel along the upper surface boundary lines of the three rhomboidal pillars, and a hexagonal portion aligned with the hexagonal upper surface of the boiler body. The outer end of the trifurcated portion is connected to every other three vertices A of the six vertices of the hexagonal portion, and the hexagonal portion further includes three vertices A to which the trifurcated portion is joined. It has two overhanging portions extending along the sides of the hexagon and one overhanging portion extending along one of the sides of the hexagon from three vertices B to which the three-pronged portions are not connected, and the outer end of the overhanging portion is Supported on the inner surface of the pressure vessel Body suspended structure of hexagonal pressurized Doso boiler which by that, that said. 2. A steam header provided on the lower surface of a boiler body housed in a pressure vessel, and an ash chute extending below the steam header and constituted by a water pipe wall, wherein the boiler body is mutually The steam header is composed of three adjacent rhomboidal pillars, and the steam header includes a three-pronged portion extending in three radial directions from the center of the pressure vessel along a lower surface boundary line of the three rhomboidal pillars, and a hexagonal lower surface of the boiler body. And a hexagonal portion aligned with the three-sided portion, and every other three sides E of the six sides of the hexagonal portion are connected by a plurality of connecting steam pipes parallel to the remaining side F, The side F that is not connected by the connecting steam pipe and the outermost steam steam pipe are connected by a plurality of supporting steam pipes that are parallel to the side E of the hexagonal portion and are spaced apart from each other. Reinforcement structure of main body of square pressure fluidized bed boiler