JP3477697B2 - Cyclone support structure in hexagonal boiler - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressurized fluidized bed boiler, and more particularly to a cyclone support structure in 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 under development as a new boiler replacing the conventional fine powder boiler.

Such a pressurized fluidized bed boiler has, for example, as shown in FIG. 6, a boiler main body 1, a cyclone 2, a bed material storage container 3 and the like stored in a pressure container 4, which is externally connected. The supplied coal C is burned in the boiler main 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) for work (for example, a generator). Drive).

Further, a fluidized bed B in which bed material such as coal ash or sand is fluidized by air A supplied from below is formed in the boiler body 1, and in the fluidized bed B, steam is contained. The evaporator 5, the superheater 6, and the reheater 7 for generating 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. 7 is a hexagonal pressurized fluidized bed boiler in which the boiler body 1 is in the form of a hexagonal column (hereinafter referred to as a hexagonal boiler).
FIG. In this figure, the hexagonal boiler is
Similar to FIG. 6, the boiler main body 1, the cyclone 2, the bed material storage container 3, etc. are stored in the pressure container 4, and the coal supplied from the outside is burned in the boiler main body 1, The exhaust gas is sent to the cyclone 2 via the exhaust gas manifold 8, and the exhaust gas from which the ash has been removed by the cyclone 2 is supplied to an external gas turbine (not shown) via the cyclone outlet duct 9 to work. ing.

[0006]

The cyclone 2 is composed of a combination of a primary cyclone and a secondary cyclone, and in the above-mentioned hexagonal boiler, it is necessary to arrange a large number of cyclones 2 above the pressure vessel 4. However, in the conventional cyclone support structure, the cyclone support beam is complicated and large, the cyclone and the cyclone support beam increase the overall height of the pressure vessel 4, the space around the cyclone 2 is narrow, and maintenance is difficult to perform. It is difficult to follow thermal expansion, and excessive stress is locally generated due to an earthquake.
There were problems such as.

That is, in the conventional cyclone support structure, a large number of cyclones 2 are hung from an upper dish-shaped end plate, or a cyclone support beam is constructed by a truss structure surrounding the central exhaust gas manifold 8 and the exhaust gas is It supported the individual bodies of the manifold and cyclones. However, if it is hung from the end plate, the end plate may buckle due to the weight of the cyclone, and the displacement due to the internal pressure of the end plate is large, so it was necessary to use a spring hanger type suspension device. Further, if the truss structure is used, the support beam cannot be passed straight through the central exhaust gas manifold 8 in the diametrical direction of the pressure vessel 4, the truss becomes complicated and the total height of the truss becomes large, and the truss member is twisted. , The support beam became complicated and large. Further, because of this, the total height of the pressure vessel 4 becomes high, the space around the cyclone is narrow, and maintenance is difficult.

Further, since the cyclone and the cyclone inlet duct become hot, it is necessary for the cyclone to follow the thermal expansion of the pressure vessel in the radial direction, but it is difficult for the conventional cyclone support structure to follow this thermal expansion. There was a problem that excessive stress was partially generated or excessive stress was locally generated during an earthquake.

The present invention was created to solve the above-mentioned various problems. That is, the object of the present invention is that the structure is simple and small, the overall height of the pressure vessel can be reduced, a sufficient maintenance space can be secured around the cyclone, maintenance can be easily performed, thermal expansion can be followed, and a local area due to an earthquake (EN) Provided is a cyclone support structure in a hexagonal boiler in which excessive stress does not occur.

[0010]

SUMMARY OF THE INVENTION According to the present invention, there is provided a three, three inner primary cyclone and two outer secondary cyclone, arranged around a central exhaust manifold.
A pair of first cyclone assemblies, and a pair of second cyclone assemblies each disposed between the first cyclone assembly and each having an inner primary cyclone and an outer primary cyclone and two outer secondary cyclones. A support structure for a cyclone in a hexagonal boiler is provided. According to a preferred embodiment of the invention, the inlet ducts of the two primary cyclones of each said pair are integrally formed.

Further, the central portion is close to the exhaust gas manifold, supports the exhaust gas manifold, and is approximately 60 mm apart from each other.
Three horizontal main cyclone support beams, which are arranged to intersect each other at an angle of ° and whose both ends are supported by the inner surface of the pressure vessel, and both sides of each cyclone, which extend in the radial direction of the pressure vessel, and whose both ends are the main cyclone support beams. And a plurality of sub cyclone support beams supported on the inner surface of the pressure vessel, and connected to each cyclone, extend horizontally on both sides of each cyclone almost orthogonal to the sub cyclone support beams, and both ends are supported by the sub cyclone support beams. And a plurality of auxiliary cyclone support beams. It is preferable that the sub cyclone support beam has horizontal guides that support both ends of the auxiliary cyclone support beam so as to be movable in the radial direction of the pressure vessel.

Further, three horizontal main ash cooler support beams whose central portions are spaced apart from the exhaust gas manifold and at an angle of approximately 60 ° to each other and whose both ends are supported by the inner surface of the pressure vessel, and whose both ends are And three horizontal auxiliary ash cooler support beams supported by the main ash cooler support beams.

[0013]

With the above-described structure of the present invention, three bed pairs of the first cyclone assembly and six pairs of the second cyclone assembly are provided, and six bed material storage containers and primary beds are evenly arranged at 60 ° intervals on each side of the hexagonal boiler. Because the cyclones can be placed close to each other in the vertical direction without interference,
Space can be used effectively, the height of the pressure vessel can be shortened (for example, about 6 m), significant cost reduction can be achieved, and the inlet ducts of the two primary cyclones of each pair are integrally formed. , Sufficient space for maintenance can be secured between the cyclones,
Since the arrangement is symmetrical and the assemblies are substantially the same, the overall arrangement can be made orderly and the performance of each cyclone can be made uniform.

Further, the cyclone support beam and the ash cooler support beam are all straight beams, which can reduce the design man-hour, manufacturing / installation cost and weight, and the upper surface of the ash cooler support beam can be used as a maintenance passage. Easy to maintain, bed material storage container,
Since the ash cooler and the like are regularly arranged at intervals of 60 °, there are many common parts and the number of parts can be reduced.

Further, since the auxiliary cyclone support beam has horizontal guides for supporting both ends of the auxiliary cyclone support beam so as to be movable in the radial direction of the pressure vessel, it is possible to follow the thermal expansion and Since the horizontal guides prevent both ends of the auxiliary cyclone support beam from moving up and down, the members will not be twisted even in the event of an earthquake and overstress will not occur locally.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. In the drawings, common parts are designated by the same reference numerals and used. FIG. 1 is a side view of an upper portion of a hexagonal pressurized fluidized bed boiler (hexagonal boiler) in which the boiler main body is in the form of a hexagonal prism. In this figure, a substantially cylindrical exhaust gas manifold 8 is arranged in the center of a hexagonal boiler, and a plurality of cyclones 2 are arranged around it. The cyclone 2 is composed of a primary cyclone 12 and a secondary cyclone 14. Exhaust gas enters the inlet duct 12a of the primary cyclone 12 from the exhaust gas manifold 8 and the exhaust gas from which ash has been separated by the primary cyclone 12 further enters the secondary cyclone 14. Further fine ash is removed, and then exhaust gas is supplied to an external gas turbine (not shown) through the cyclone outlet duct 9.
As shown, the primary cyclone 12 has a larger diameter than the secondary cyclone 14, and most of the primary cyclones 12 are located on the inside and the secondary cyclones 14 are located on the outside. Thereby, the structure of the inlet duct 12a of the primary cyclone 12 can be simplified.

FIG. 2 is a view taken in the direction of arrow A in FIG. In this figure, the supporting structure of the cyclone in the hexagonal boiler of the present invention comprises three pairs of first cyclone assemblies 16 arranged around the central exhaust gas manifold 8 at intervals of approximately 120 °, and the first cyclone assembly 16. 6 pairs of second cyclone assemblies 18 disposed therebetween.

Each pair of first cyclone assemblies 16 comprises:
It is composed of two inner primary cyclones 12 and two outer secondary cyclones 14, and the inlet ducts of the two primary cyclones of each pair are integrally formed. Further, the three pairs of first cyclone assemblies 16 are composed of the same parts,
They are arranged symmetrically with respect to the center line X-X in the figure.

Each pair of second cyclone assemblies 18 comprises
Each is composed of an inner primary cyclone 12 and an outer primary cyclone 13, and two outer secondary cyclones 14, and the inlet ducts of the two primary cyclones of each pair are integrally formed. The six pairs of the second cyclone assemblies 18 are composed of the same parts or parts opposite to each other except the parts on both sides of the part through which the cyclone outlet duct 9 passes, and are symmetrical with respect to the center line X-X in the figure. It is arranged.

According to the above-mentioned structure, the three pairs of the first cyclone assemblies 16 and the six pairs of the second cyclone assemblies 18 form the six bed material storage containers and the primary beds which are evenly arranged at intervals of 60 ° on each side of the hexagonal boiler. Since the cyclones can be placed close to each other in the vertical direction without interfering with each other, space can be effectively used, and the height of the pressure vessel can be shortened (for example, about 6 m), which enables significant cost reduction. Since the inlet ducts of the two primary cyclones of each pair are integrally formed, sufficient space for maintenance can be secured between the cyclones, and the layout is symmetrical, and each assembly is almost the same, so Can be arranged in order, and the performance of each cyclone can be made uniform. Also, by using a part of the primary cyclones as outer primary cyclones 13 as shown in the figure, it is possible to arrange a large number of cyclones on the outer side as a whole rather than on the inner side, and to widen the intervals between the cyclones almost uniformly. it can.

FIG. 3 is a view on arrow B of FIG. In this figure, the cyclone support structure in the hexagonal boiler of the present invention further includes three horizontal main cyclone support beams 20.
And a plurality of auxiliary cyclone support beams 22 and a plurality of auxiliary cyclone support beams 24. The three horizontal main cyclone support beams 20 are close to the exhaust gas manifold 8 at the central portion thereof and support the exhaust gas manifolds, and each of the horizontal main cyclone support beams 20 has approximately 60
They are arranged so as to intersect each other at an angle of ° and both ends are supported by the inner surface of the pressure vessel 4. In addition, a plurality of sub cyclone support beams 22
Extends radially of the pressure vessel on each side of each cyclone,
Both ends are supported by the main cyclone support beam 20 and the inner surface of the pressure vessel 4. Further, a plurality of auxiliary cyclone support beams 24
Are connected to the respective cyclones, extend horizontally on both sides of each cyclone substantially orthogonal to the sub-cyclone support beams 22, and both ends are supported by the sub-cyclone support beams 22.

FIG. 4 is a supporting structure (B) different from the DD sectional view (A) of FIG. As shown in FIG. 4A, the auxiliary cyclone support beam 22 has horizontal guides 23 that support both ends of the auxiliary cyclone support beam 24 so as to be movable in the radial direction of the pressure vessel. The upper portion of the horizontal guide 23 is located at a slight distance from the upper surface of the auxiliary cyclone support beam 24, and guides the auxiliary cyclone support beam 24 so that it cannot move up and down. Further, as shown in FIG. 4 (B), it is preferable that a roller 25 is provided on the lower surface of the end portion of the auxiliary cyclone support beam 24 so that the pressure vessel moves smoothly in the radial direction.

With the configuration shown in FIGS. 3 and 4, the cyclone support beams 20, 22, 24 are all straight beams, and the design man-hour, manufacturing / installation cost and weight can be reduced, and the cyclone can be used as a bed material storage container. Since it can be arranged between the two, the space can be effectively used, the height of the pressure vessel can be shortened (for example, about 6 m), and the cost can be significantly reduced. Further, since the sub cyclone support beam 22 has the horizontal guides 23 that support both ends of the auxiliary cyclone support beam 24 so as to be movable in the radial direction of the pressure vessel,
This horizontal guide 23 can follow the thermal expansion.
As a result, both ends of the auxiliary cyclone support beam 24 are prevented from moving up and down, so that the members will not be twisted even during an earthquake and excessive stress will not be locally generated.

FIG. 5 is a view on arrow C of FIG. In this figure, the cyclone support structure in the hexagonal boiler of the present invention is further arranged such that the central portion is spaced from the exhaust gas manifold 8 and at an angle of approximately 60 °, and both ends are supported by the inner surface of the pressure vessel 4. Also provided are three horizontal main ash cooler support beams 26 and three horizontal sub ash cooler support beams 28 supported at both ends by the main ash cooler support beams 26. As a result, the ash cooler support beams 26, 28 are all straight beams, the number of design steps, manufacturing / installation costs and weight can be reduced, and the upper surfaces of the ash cooler support beams 26, 28 can be used as a maintenance passage, so that the cyclone can be used. Is easy to maintain, and the bed material storage container, ash cooler, and the like are arranged at regular intervals of 60 °, so that there are many common parts and the number of parts can be reduced.

As described above, according to the cyclone supporting structure of the hexagonal boiler of the present invention, the six bed material storage containers, which are evenly arranged at 60 ° intervals on each side of the hexagonal boiler, interfere with the primary cyclone. Since they can be placed close to each other in the vertical direction without using them, it is possible to use the space effectively and reduce the height of the pressure vessel.
A space for maintenance can be secured between the cyclones, symmetrical and orderly arrangement can be made to equalize the performance of each cyclone, and the cyclone support beam and the ash cooler support beam are all straight beams, and Can reduce manufacturing and installation costs and weight,
Since the upper surface of the ash cooler support beam can be used as a maintenance passage, cyclone maintenance is easy, and the bed material storage container, ash cooler, etc. are arranged in an orderly manner, so there are many common parts and it is possible to reduce the number of parts. The cyclone support beam can follow the thermal expansion, and it does not twist even in the event of an earthquake, and no local overstress occurs.

[0026]

Therefore, the supporting structure of the cyclone in the hexagonal boiler according to the present invention has a simple structure and a small size, the total height of the pressure vessel can be reduced, a sufficient maintenance space can be secured around the cyclone, and maintenance can be performed easily. It has an excellent effect that it is easy to follow thermal expansion and does not generate excessive stress locally due to an earthquake.

[Brief description of drawings]

FIG. 1 is a partial side view of an upper portion of a hexagonal pressurized fluidized bed boiler (hexagonal boiler).

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a view on arrow B of FIG.

FIG. 4 is a support structure (B) different from the DD cross-sectional view (A) of FIG. 3.

5 is a view on arrow C of FIG. 1. FIG.

FIG. 6 is an overall configuration diagram of a conventional pressurized fluidized bed boiler.

FIG. 7 is an overall configuration diagram of a hexagonal pressurized fluidized bed boiler.

[Explanation of symbols]

1 Boiler body 2 cyclone 3 bed material storage containers 4 Pressure vessel 5 evaporator 6 heater 7 Reheater 8 exhaust gas manifold 9 Cyclone outlet duct 12 Inside primary cyclone 13 Outer primary cyclone 14 Secondary cyclone 16 First Cyclone Assembly 18 Second Cyclone Assembly 20 Main cyclone support beams 22 Sub cyclone support beam 23 Horizontal guide 24 Auxiliary cyclone support beam 26 Main Ash Cooler Support Beam 28 Sub-ash cooler support beam

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) F23J 15/00 F23B 1/02 F23C 10/16

Claims (5)

(57) [Claims] 1. A pair of first cyclone assemblies, which are arranged around a central exhaust gas manifold and consist of two inner primary cyclones and two outer secondary cyclones, and between the first cyclone assembly, respectively. A support structure for a cyclone in a hexagonal boiler, comprising one inner primary cyclone and an outer primary cyclone, and six pairs of second cyclone assemblies consisting of two outer secondary cyclones. 2. The cyclone support structure for a hexagonal boiler according to claim 1, wherein the inlet ducts of the two primary cyclones of each pair are integrally formed. 3. A horizontal main cyclone having a central portion supporting the exhaust gas manifold in the vicinity of the exhaust gas manifold, intersecting each other at an angle of about 60 °, and having both ends supported by the inner surface of the pressure vessel. A support beam and a plurality of sub cyclone support beams that extend in the radial direction of the pressure vessel on both sides of each cyclone and are supported at both ends by the main cyclone support beam and the inner surface of the pressure vessel, and are connected to each cyclone, and The cyclone for a hexagonal boiler according to claim 1, further comprising: a plurality of auxiliary cyclone support beams that extend horizontally at right angles to the sub cyclone support beam and that are supported at both ends by the sub cyclone support beam. Support structure. 4. The hexagonal boiler according to claim 3, wherein the auxiliary cyclone support beam has a horizontal guide that supports both ends of the auxiliary cyclone support beam so as to be movable in the radial direction of the pressure vessel. Cyclone support structure. 5. Three horizontal main ash cooler support beams, whose central portion is spaced from the exhaust gas manifold and at an angle of approximately 60 ° to each other, and whose both ends are supported by the inner surface of the pressure vessel, and whose both ends are The support structure for a cyclone in a hexagonal boiler according to claim 1, further comprising: three horizontal auxiliary ash cooler support beams supported by the main ash cooler support beam.