JP3346490B2 - Hexagonal pressurized fluidized bed boiler main body suspension structure and main body reinforcement structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art A pressurized fluidized bed boiler (Pressurized Fluidized Bed Combuster) that fluidly burns coal under pressure is
Combined cycle combined with gas turbine has thermal efficiency of 40% or more, high desulfurization rate in furnace, NO
Due to its features such as low x generation, it is currently being developed as a new type of boiler that replaces the conventional fine-powder boiler. Such a pressurized fluidized bed boiler is shown in FIG.
As shown in FIG. 1, the boiler body 1, the cyclone 2, the bed material storage container 3, and the like are configured to be stored in the pressure vessel 4, and the coal C supplied from the outside is burned in the boiler body 1, The exhaust gas is sent to the cyclone 2, and the exhaust gas from which the ash has been removed by the cyclone 2 is supplied to an external gas turbine (not shown) to perform work (for example, drive a generator). Further, a fluidized bed B in which bed materials such as coal ash and sand are fluidized by air A supplied from below is formed in the boiler main body 1. Evaporator 5, superheater 6, and reheater 7 are inserted. Due to the heat generated by the combustion of the coal in the fluidized bed B, the water evaporates in the evaporator 5 to become steam, and the steam is further heated in the superheater 6 to become superheated steam. This superheated steam is provided outside. The steam turbine (not shown) expands and works. Further, the steam whose temperature has been lowered by the steam turbine is heated again by the reheater 7 to become superheated steam, and works again by 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 has a hexagonal column shape. In this figure,
The hexagonal fluidized-bed boiler has a configuration in which a boiler main body 1, a cyclone 2, a bed material storage container 3, and the like are stored in a pressure vessel 4, as in FIG. 1, the exhaust gas is sent to a cyclone 2 via an exhaust gas manifold, and the exhaust gas from which the ash has been removed by the cyclone 2 is supplied to an external gas turbine (not shown) for work. . FIG.
It is a perspective view which shows the boiler main body periphery of a hexagonal fluidized-bed boiler, It consists of the boiler main body 1 of a hexagonal column, its bottom part 10, and the support beam 9 which suspends the boiler main body 1. FIG. The boiler body 1 and its bottom 10 are shown separately for clarity. The boiler body 1 has a configuration in which three rhombic columns 1a, 1b, and 1c are adjacent to each other. There are no partitions inside, each surface of the hexagonal column is formed of a water pipe wall, and each corner of the hexagonal column is formed of a header. Have been. On the upper surfaces of the three rhombic columns 1a, 1b, 1c, there are rhombic openings, through which the inner tube can be taken out. The bottom portion 10 of the boiler main body 1 is composed of a steam header 8 formed of a hexagon and a three-pronged portion, and an ash chute 11, and a bed material containing ash can be taken out from the lower surface of the steam header 8 via the ash chute 11. I can do it. Further, two steam headers 20 (Cold Reheat Pipes) for low-temperature reheat steam are arranged on the bottom 10 of the boiler main body 1 so as to face each of the three rhombic columns 1a, 1b, and 1c. (Only the diamond-shaped pillar 1a is shown in the figure). FIG. 7 is a horizontal sectional view taken along line AA of FIG. In this figure, a boiler body 1 has a hexagonal horizontal section and six vertical water pipe walls 12a, 12b.
And a hexagonal closed back stay 14. The inside of the hexagon is 3 ° away from the center by 120 °.
The book is divided into three spaces by a virtual dashed line. That is, the inside of the hexagon is formed by two adjacent water pipe walls 12a, 1a.
A horizontal section having 2b as two sides of a parallelogram is formed of three parallelogram spaces. Each space has one water pipe wall 1
A first inner tube group 16a which is parallel to 2a and one end of which is adjacent to the other water tube wall 12b and whose vertical planes are parallel to each other; and the first layer tube group which is parallel to one water tube wall 12a and Inner tube group 1
6a, one end of which is adjacent to the other end and whose vertical faces are parallel to each other.
And the in-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. Accordingly, a large load (for example, about 1200 tons), which is the total weight of the boiler main body 1 and the bed material (fluid medium) therein, acts on the support beam 9. The support beam 9 has three rhombic columns 1a, 1b, 1c.
A beam cannot be provided above the diamond-shaped opening because the inner layer tube is taken out from the diamond-shaped opening on the upper surface of the diamond. for that reason,
The support beam 9 includes a triangular portion 9a and a hexagonal portion 9 as shown.
and about half of the total weight acts on the forked portion 9a. That is, approximately 1/4 (approximately 300 tons) of the total weight acts on each of the vertices A connected to the fork 9a, and approximately 1/12 of the total weight on each of the vertices B not connected to the fork 9a. (Approximately 100 tons). For this reason, as shown in FIG.
If overhangs are provided on both sides of three sides of the sides and the overhangs are supported on the inner surface of the pressure vessel, the loads received at the vertices A and B are uneven, and the overhangs from the apex A are supported. There is a problem that an excessive stress is partially generated in the pressure vessel. The first invention of the present invention has been made to solve such a problem. That is, an object of the first invention of the present invention is to provide a hexagonal pressurized fluidized-bed boiler main body suspension structure capable of equalizing the load acting on the projecting portion of the support beam and reducing 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 pressure difference between the inside and outside of the boiler body 1 is 6000 mmAq to 7000 m.
mAq, and an external pressure of 6 to 7 ton / m ² acts on the boiler body. As shown in FIG. 7, in-boiler tube groups 16a and 16b are densely arranged inside the boiler main body 1,
Since they are connected by a connecting member (not shown), they can receive an external pressure. However, as shown in FIG.
The bottom portion 10 of the boiler main body 1 is composed of a steam header 8 formed of a hexagon and a trifurcation, and an ash chute 11, and three parallelogram portions surrounded by the steam header 8 have one side F thereof.
Are connected in parallel to each other. Therefore, there is a problem that the steam header 8 (shown by F in the figure) not connected by the connecting steam pipe 22 bends inward when subjected to an external pressure, and a large stress is generated. The second invention of the present invention has been made to solve such a problem. That is, an object of the second invention of the present invention is to provide a main body reinforcing structure in which a steam header at the bottom of a boiler main body does not generate large bending or stress even when subjected to an external pressure due to a differential pressure.

[0005]

According to the present invention, a boiler body stored in a pressure vessel and forming a fluidized bed therein,
A support beam for suspending the boiler body, wherein the boiler body comprises three diamond-shaped pillars adjacent to each other, and the support beam has a radius from the center of the pressure vessel along the upper surface boundary of the three diamond-shaped pillars. And a hexagonal portion aligned with the hexagonal top surface of the boiler body, and the outer end of the trifurcation portion is formed at every third vertex of the six vertices of the hexagonal portion. Connected to two vertices A,
The hexagonal portion further includes two overhanging portions extending along three sides of the hexagon from three vertices A to which the three-pointed portion is connected, and one of the sides of the hexagon from three vertices B to which the three-pointed portion is not connected. And an outer end of the overhang portion is supported on an inner surface of the pressure vessel. You.

Further, according to the present invention, there is provided a steam header provided on the lower surface of a boiler main body stored in a pressure vessel, and an ash chute extending below the steam header and constituted by a water pipe wall. The boiler body includes three rhombic columns adjacent to each other, the steam header includes a three-pronged portion extending in three directions in the radial direction from the center of the pressure vessel along a lower surface boundary of the three rhombic columns, and the boiler body. A hexagonal portion aligned with the hexagonal lower surface of the hexagonal portion, and every other three sides E among the six sides of the trifurcated portion and the hexagonal portion are:
A plurality of connecting steam pipes connected by a plurality of connecting steam pipes parallel to the remaining side F, and a side F and an outermost connecting steam pipe not connected by the connecting steam pipe are parallel to and spaced apart from the side E of the hexagonal portion. The main body reinforcement structure of the hexagonal pressurized fluidized-bed boiler, which is connected by the supporting steam pipe of (1).

[0007]

According to the first configuration of the present invention, the supporting beam for suspending the boiler body is composed of a trifurcated portion and a hexagonal portion, and the outer end of the trifurcated portion is one of the six vertexes of the hexagonal portion.
Connected to every third vertex A, and the hexagonal part
Two protruding portions extending along three sides of the hexagon from three vertices A to which the three-pronged portion is connected, and 1 extending along one of the sides of the hexagon from three vertices B to which the three-pronged portion is not connected.
Since the outer end of the overhanging portion is supported on the inner surface of the pressure vessel, even if approximately half of the total weight acts on the fork, the apex of the vertex A connecting to the fork Each acts on only about 1/8 (about 150 tons) of the total weight. Therefore, the load is close to about 1/12 (about 100 tons) of the total weight acting on the vertex B that is not connected to the trifurcation, and the loads received at the vertex A and the vertex B are equalized. Can be reduced.

Further, according to the second configuration of the present invention, the steam header on the lower surface of the boiler is composed of a trifurcated portion and a hexagonal portion, and every other three of the six sides of the trifurcated portion and the hexagonal portion is formed. Two sides E are connected by a plurality of connecting steam pipes parallel to the remaining side F, and the side F not connected by the connecting steam pipe and the outermost connecting steam pipe are parallel to the side E of the hexagonal portion and Since the steam headers are connected by a plurality of support steam pipes spaced apart from each other, the rigidity of the steam header on the side F connected to the support steam pipe and the connection steam pipe increases, and the steam header hardly bends even when subjected to external pressure, and the generated stress also decreases. Become smaller.

[0009]

Preferred embodiments of the present invention will be described below with reference to the drawings. In the drawings, common 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 is omitted here to avoid duplication. FIG. 1 is a perspective view similar to FIG. 6 showing a main body suspension structure and a main body reinforcement 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 main body suspension structure of a hexagonal pressurized fluidized bed boiler according to the present invention includes a boiler body 1 that is stored in a pressure vessel 4 and forms a fluidized bed therein, and suspends the boiler body 1. A boiler body 1 having a support beam 9
Consists of three rhombic columns 1a, 1b, 1c adjacent to each other. The support beam 9 has three rhombic columns 1a, 1b, 1
c, a triangular portion 9a extending radially in three directions from the center of the pressure vessel 4 along the upper boundary of the pressure vessel 4, and a hexagonal portion 9b aligned with the hexagonal upper surface of the boiler main body 1. The end is connected to every other three vertices A among the six vertices of the hexagonal portion 9b. Hexagon part 9b
Further, two overhanging portions 30 extending along three sides of the hexagon from three vertices A to which the three-forked portions 9a are connected, and one of the sides of the hexagon from three vertices B to which the three-forked portions 9a are not connected. And one extending 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 such a configuration, even if approximately half of the total weight acts on the fork, the apex A connected to the fork
Only about 1/8 of the total weight (about 150 tons). Therefore, the load is close to about 1/12 (about 100 tons) of the total weight acting on the vertex B that is not connected to the forked part, and the loads received at the vertex A and the vertex B are uniformed.
Stress generated in the portion of the pressure vessel 4 that supports the overhang from the vertex A can be reduced.

FIG. 3 is an enlarged perspective view of a portion C in FIG. In this figure, the outer end of the overhang portion 30 is placed on the upper surface of a horizontal support member 32, and hanging members 33 are provided at both ends of the supporting member 32. The upper end of the suspension member 35 is pivotally connected to the inner surface of the pressure vessel 4 by another horizontal pin 36. The same applies to the support structure of the overhang portion 31. With this configuration, it is possible to allow the support beam 9 to move in the radial direction and the circumferential direction, and to smoothly transmit the downward load acting on the support beam 9 to the pressure vessel 4.

FIG. 4 is a side sectional view taken along line DD of FIG. 1 and 4, a main body reinforcing structure of a hexagonal pressurized fluidized-bed boiler according to the present invention includes a steam header 8 provided on a lower surface of a boiler main body 1 stored in a pressure vessel.
And an ash chute 11 extending below the steam header 8 and formed of a water pipe wall. Further, the boiler main body is composed of three rhombic columns 1a, 1b, 1c adjacent to each other. Furthermore, according to the invention, the steam header 8 comprises three rhombic columns 1
a triangular portion 8a extending in three directions in the radial direction from the center of the pressure vessel along the lower boundary lines of the a, 1b and 1c, and a hexagonal portion 8b aligned with the hexagonal lower surface of the boiler body 1; 8a and one of the six sides of the hexagonal portion 8b
Every other three 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 pipe 22 and the outermost connecting steam pipe 22 are connected to the hexagonal portion 8b. A plurality of supporting steam pipes 24 parallel to and spaced from the side E;
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, so that the steam header 8b is less likely to bend even when subjected to an external pressure, and the generated stress is reduced.

[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,
Stress generated in the portion of the pressure vessel 4 that supports the overhang from the vertex A can be reduced. Further, according to the second configuration, the rigidity of the steam header 8b is increased, and the steam header 8b is less likely to bend even when subjected to an external pressure, and the generated stress is 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 equalize the load acting on the projecting portion of the support beam and reduce the stress generated in the pressure vessel part, And even if it receives an external pressure due to the differential pressure, no large bending or stress is generated in the steam header at the bottom of the boiler body.
Has excellent effects.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the periphery of a boiler main 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 portion C in FIG. 2;

FIG. 4 is a side sectional view taken along line DD of FIG. 1;

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

FIG. 6 is a perspective view showing a periphery of a boiler main body of a hexagonal fluidized bed boiler.

FIG. 7 is a horizontal sectional view taken along the line AA in FIG. 4;

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

[Explanation of symbols]

 DESCRIPTION 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 Trifurcation part 8b Hexagon part 9 Support beam 9a Trifurcation part 9b Hexagon part 10 Bottom part of boiler body 11 Ash Chutes 12a, 12b Water pipe walls 16a, 16b In-layer pipe group 18 Steam header 20 Steam header for low-temperature reheat steam 22 Connected steam pipe 24 Support steam pipe 30, 31 Overhang 32 Support member 33 Suspension fitting 34, 36 Pin 35 Suspension member A Air B Fluidized bed C Coal

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F22B 37/24 F22B 1/02 F23C 10/16

Claims (2)

(57) [Claims] A boiler main body which is stored in a pressure vessel and forms a fluidized bed therein; and a support beam for suspending the boiler main body, wherein the boiler main body comprises three rhombic columns adjacent to each other, The support beam comprises a trifurcated portion extending in three directions in the radial direction from the center of the pressure vessel along the upper surface boundary of the three rhombic columns, and a hexagonal portion aligned with the hexagonal upper surface of the boiler body; The outer ends of the trifurcated portions are connected to every other three vertices A among the six vertices of the hexagonal portion, and the hexagonal portions are further connected to three vertices A to which the triangular portions are connected. 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 trifurcated 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 a lower surface of a boiler main body stored in a pressure vessel, and an ash chute extending below the steam header and formed of a water pipe wall, wherein the boiler main bodies are mutually connected. The steam header comprises three adjacent rhombic columns, wherein the steam header includes a trifurcated portion extending in three directions in the radial direction from the center of the pressure vessel along a lower boundary of the three rhombic columns, and a hexagonal lower surface of the boiler body. And a triangular portion aligned with the triangular 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 not connected by the connecting steam pipe and the outermost steam steam pipe are connected by a plurality of supporting steam pipes parallel to and spaced from the side E of the hexagonal portion. Reinforcement structure of rectangular pressurized fluidized bed boiler