JPH11166706A - Hopper for special-form furnace bottom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit particles to substantially evenly fall and be discharged from the entire section even if the form of a horizontal section is special. SOLUTION: A hopper for special-form furnace bottom comprises a funnel-shaped outer hopper and a collection portion 14 provided below the outer hopper 1 with the combined portion therebetween being divided with a horizontal board 13. The upper portion of the collection portion 14 is divided with vertical boards which are mutually vertical and is constituted of a plurality of independent chambers which are communicated with each other at the lower portion. The horizontal board in each of the independent chambers is provided with a through hole. Further, a plurality of conduits 16 are provided within the outer hopper, with the lower end portions thereof being fixed to the horizontal board 13 so as to be communicated with the independent chambers, while the upper ends thereof is extended upward. The upper portions of the individual conduits 16 are substantially flatly and evenly arranged in the horizontal section of the special-form furnace bottom. Each of the conduits 16 has the same inclined portion 16a which is larger than the angle of repose of particles. Further, because the conduit (tube A) which is extended to the furnace bottom portion close to the collection portion 14 is relatively thin, and the upper and lower portions of the inclined portion are perpendicularly constituted, a flow is unlikely to occur therethrough. On the contrary, because the conduit (tube B) which is extended far from the collection portion is relatively thick and constituted only of the inclined portion, with the upper and lower ends thereof being horizontally cut to have oval openings, a flow is likely to occur.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modified hearth hopper for dropping and discharging particles from a deformed bottom, and more particularly to a hopper for 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.

Further, in recent years, there has been a demand for increasing the capacity of such a pressurized fluidized-bed boiler, and a hexagonal pressurized fluidized-bed boiler in which the horizontal cross section of a boiler main body is formed in a hexagon has been proposed (for example, Japanese Patent Application Laid-Open No. H11-157556). JP-A-6-337102, JP-A-6-19
3803, JP-A-7-35305, JP-A-7-13
No. 9722, JP-A-7-293801, JP-A-8-3
No. 27016, JP-A-9-14605, etc.).

FIG. 5 is an overall configuration diagram of such a hexagonal pressurized fluidized bed boiler. In this figure, the pressurized fluidized-bed boiler has a configuration in which a boiler body 1, a cyclone 2, a bed material storage container 3, and the like are stored in a pressure container 4.
Coal supplied from the outside is burned in the boiler main body 1, and the exhaust gas is passed through the exhaust gas manifold 5 to the cyclone 2.
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. 6 is a perspective view showing the boiler body 1 of FIG. 5 and the furnace bottom 6 thereof. In this figure, the boiler body 1 and the furnace bottom 6 are shown separately for clarity. As shown in the figure, the boiler body 1 has three rhombic columns 1a, 1b,
Reference numeral 1c denotes an adjacent configuration, in which there is no partition inside, each surface of the hexagonal prism is formed by a water pipe wall, and each corner of the hexagonal prism is configured by a header. The furnace bottom 6 of the boiler main body 1 is composed of a steam header 7 formed of a hexagon and a trifurcation, and an ash chute 8. Bed material (particles) containing ash from the lower surface of the steam header 7 via the ash chute 8. To take out. A heat exchanger (not shown) for cooling the bed material is installed inside the ash chute 8.

[0006]

At the lower part of the above-mentioned conventional ash chute 8, a hopper 9 for a furnace bottom for dropping and discharging bed material (particles) is provided. However, since the modified hearth hopper 9 drops and discharges particles from the deformed bottom (elongated parallelogram) shown in FIG. 6, the falling velocity of the particles differs depending on the position of the cross section, and the lower part is simply made thinner. The funnel-shaped hopper has a problem that the contents cannot be dropped uniformly.

Therefore, for example, the particles located at the acute corner of the parallelogram are located farthest from the outlet of the hopper located at the center, so that they hardly descend unless other particles are eliminated. However, there is a problem that the heat exchanger does not function at the sharp corner even if the heat exchanger is provided. Therefore, in the conventional ash chute, a plurality of heat exchangers inside the ash chute were arranged in a vertical direction at a location where the flow of particles is good, but the height of the ash chute increased,
There was a problem that the container height of the hexagonal pressurized fluidized bed boiler was increased.

In other words, as in the case of the above-mentioned hexagonal pressurized fluidized-bed boiler, when the hopper has a large horizontal cross-sectional area and has a deformed cross-sectional shape such as an elongated parallelogram, a horizontal distance from the discharge port is required. The contents of large parts exit the outlet slowly, and the upper part of the heat transfer (cooling / heating etc.)
In some cases, the heating (cooling) is not uniform, and there is a problem that the heat transfer tube group at the site where the falling speed is slow loses its meaning.

The present invention has been made to solve the above problems. That is, the object of the present invention is:
It is an object of the present invention to provide a deformed hearth hopper which has a large horizontal cross-sectional area and has an irregular cross-sectional shape such as an elongated parallelogram so that particles can be almost uniformly dropped and discharged from the entire cross-section.

[0010]

According to the present invention, there is provided a hopper for dropping and discharging particles from a furnace bottom having an irregular horizontal cross-sectional shape, comprising a funnel-shaped outer hopper and a collecting portion provided at a lower portion thereof. The connecting portion between the outer hopper and the collecting portion is partitioned by a horizontal plate, and the upper portion of the collecting portion is composed of a plurality of independent chambers separated by a vertical plate and communicating with each other at a lower portion, and is located in each independent chamber. Each of the horizontal plates is provided with a through hole, and an upper end extends upward in the outer hopper,
A plurality of conduits each having a lower end fixed to the horizontal plate and communicating with a plurality of independent chambers are provided, and the upper portions of the respective conduits are substantially evenly arranged in a horizontal section of the bottom of the deformed furnace, and each of the conduits is provided with particles. The conduit having the same slope portion that is larger than the angle of repose and extending to the hearth portion close to the gathering portion is configured to be relatively thin and configured vertically up and down the slope portion, and extends to the hearth portion far from the gathering portion. Is characterized by having a relatively thick and sloped portion and having upper and lower ends cut horizontally to have an elliptical opening.

According to this structure, the lower ends of the plurality of conduits are fixed to the horizontal plate separating the outer hopper and the collecting portion, and communicate with the plurality of independent chambers, respectively. Since the conduits are substantially evenly arranged in a horizontal cross section and each conduit has the same gradient that is larger than the angle of repose of the particles, the dropped particles flowing into the conduit from near the furnace bottom do not interfere with each other, and It can smoothly fall into each independent chamber without staying in the room, and fall and gather at the lower part of the collecting part and flow out. In addition, since the conduit extending to the hearth portion near the collection portion is relatively thin and the vertical portion of the slope portion is configured vertically, it becomes relatively difficult to flow, and conversely, to the hearth portion far from the collection portion. The extending conduit is relatively thick and composed only of a slope portion, and the upper and lower ends are cut horizontally so as to have an elliptical opening, so that it is relatively easy to flow, so that the heat exchanger is provided at the upper part. Even if there is, the particles can be dropped and discharged almost uniformly from the entire cross section, and the contents can be dropped uniformly, so that all the heat exchangers can function effectively.

According to a preferred embodiment of the present invention, a particle discharge pipe provided on a horizontal plate separating the outer hopper and the collecting portion, and communicating with the gap between the outer hopper and the plurality of conduits and the inside of the collecting portion, A closing plate that closes the lower end of the pipe so as to be openable and closable. With this configuration, the particles clogged in the gaps between the outer hopper and the plurality of conduits can be discharged into the collecting portion by opening the closing plate.

[0013] Further, by providing an openable / closable manhole for maintaining the inside of the collecting section, maintenance can be easily performed inside.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In addition, the same reference numerals are given to the common parts in the respective drawings, and the duplicate description will be omitted. FIG. 1 is an overall configuration diagram of a particle hopper according to the present invention, and FIG. 2 is an enlarged view of a portion A in FIG. Also, FIG.
It is sectional drawing (A) in the BB line of FIG. 1, and sectional drawing (B) in the CC line. FIG. 4 is a structural explanatory view of each conduit.

As shown in FIG. 1, a deformed hearth hopper 10 of the present invention is a hopper for dropping and discharging particles from a hearth whose horizontal cross-sectional shape is irregular, and includes a funnel-shaped outer hopper 12 and a lower portion thereof. And the collecting part 14 provided in the
With this configuration, high-temperature particles (bed material containing ash) of, for example, about 870 ° C. are cooled by a cooler (heat exchanger) to, for example, about 150 ° C. at the furnace bottom, and the particles are downwardly passed through the modified furnace bottom hopper 10. It is designed to drop and flow.

As shown in FIGS. 2 and 3B, a connecting portion between the outer hopper 12 and the collecting portion 14 is partitioned by a horizontal plate 13. Also, the upper part of the collecting part 14 is
It comprises a plurality of independent chambers 15 partitioned by a and communicating with each other at the lower part. The horizontal plates 13 located in the independent chambers 15 are provided with through holes 13a.

As shown in FIGS. 2A and 4,
A plurality of conduits 16 are provided inside the outer hopper 12, and the lower ends thereof are fixed to the horizontal plate 13 and communicate with the plurality of independent chambers 15, respectively, and the upper ends extend upward in the outer hopper 12. .

As shown in FIG. 3, the upper portion of each conduit 16 is substantially evenly arranged on a horizontal section of the modified hearth.
Also, as shown in FIG. 4, each conduit 16 has the same gradient portion 16a larger than the angle of repose of the particles. As shown in FIGS. 3A and 4, the conduit 16 (for example, the A tube in the figure) extending to the furnace bottom portion near the collecting portion 14 is relatively thin, and the upper and lower portions of the inclined portion 16a are vertical tubes 16b. On the contrary, the conduit 16 (for example, the tube B in the drawing) extending to the furnace bottom portion far from the collecting portion 14 is relatively thick and includes only the slope portion 16a. Further, the upper and lower ends of a conduit 16 (B-tube) extending from the collecting portion 14 to the furnace bottom portion are cut horizontally to have elliptical openings.

Further, as shown in FIG. 2, the modified bottom hopper 10 of the present invention is attached to a horizontal plate 13 which separates an outer hopper 12 and a collecting section 14, and a gap between the outer hopper 12 and a plurality of conduits 16 is provided. A particle discharge pipe 17 communicating with the inside of the collecting portion 14 and a closing plate 18 for opening and closing the lower end of the particle discharging pipe 17 are provided. When the closing plate 18 is opened, a gap between the outer hopper 12 and the plurality of conduits 16 is formed. Clogged particles 1
1 can be discharged into the collecting section 14. The particles 11 clogged in the gap between the outer hopper 12 and the plurality of conduits 16 are located in that portion during normal operation and have a function of keeping the conduit 16 warm.

Further, it is desirable to provide an openable / closable manhole (not shown) for maintaining the inside of the collecting section 14.

According to the configuration of the present invention described above, the lower ends of the plurality of conduits 16 are fixed to the horizontal plate 13 that partitions the outer hopper 12 and the collecting section 14 and communicate with the plurality of independent chambers 15, respectively. The upper part of each conduit 16 is substantially evenly arranged in a horizontal cross section of the modified hearth, and since each conduit 16 has the same slope that is larger than the angle of repose of the particles, it flows into the conduit 16 from near the hearth. The dropped particles can smoothly fall into the independent chambers 15 without interfering with each other and do not stay in the conduit, and can fall and gather at the lower portion of the gathering portion 14 and flow out.

Further, the conduit 16 (A pipe) extending to the furnace bottom portion near the collecting portion 14 is relatively thin and the upper and lower portions of the inclined portion 16a are vertically formed. The conduit (B tube) extending from the collecting portion 14 to the furnace bottom portion is relatively thick and includes only the inclined portion 161a, and the upper and lower ends are cut horizontally to have elliptical openings. So it is relatively easy to flow,
Even if there is a heat exchanger at the top, particles can be dropped and discharged almost uniformly from the entire cross section, and the contents can be dropped evenly, so that all heat exchangers can function effectively .

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the present invention.

[0024]

As described above, the deformed hearth hopper of the present invention has a large horizontal cross-sectional area, and even when the cross-sectional shape is irregular, such as an elongated parallelogram, particles are almost evenly distributed from the entire cross-section. It has an excellent effect that it can be dropped and discharged.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a particle hopper according to the present invention.

FIG. 2 is a partial sectional view of FIG.

FIG. 3 is an explanatory view of a conduit structure.

FIG. 4 is a vertical cross-sectional view of a collecting part.

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

FIG. 6 is a perspective view showing the boiler main body of FIG. 5 and a furnace bottom thereof.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Boiler main body 2 Cyclone 3 Bed material storage container 4 Pressure vessel 5 Exhaust gas manifold 6 Furnace bottom 7 Steam header 8 Ash chute 9 Furnace bottom hopper 10 Deformed furnace bottom hopper 11 Particles (bed material containing ash) 12 Outside hopper 13 Horizontal plate 13a Through hole 14 Collecting part 15 Independent chamber 16 Conduit 16a Inclined part 17 Particle discharge pipe 18 Closure plate

Claims (3)

[Claims] 1. A hopper for dropping and discharging particles from a furnace bottom having an irregular horizontal cross-sectional shape, comprising a funnel-shaped outer hopper and a collecting part provided below the funnel-shaped outer hopper. The connecting part is partitioned by a horizontal plate, and the upper part of the collecting part is composed of a plurality of independent chambers that are separated from each other by a vertical plate and communicate with each other at the lower part, and the horizontal plates located in each independent chamber are provided with through holes respectively. In the outer hopper, there are provided a plurality of conduits having an upper end extending upward, a lower end fixed to the horizontal plate, and communicating with a plurality of independent chambers, respectively. The conduits have the same slope that is larger than the angle of repose of the particles, and the conduits that extend to the bottom of the furnace near the confluence are relatively thin and the top and bottom of the slope are vertical. The hearth is far from the collecting part Conduits extending minute, relatively thick and consists only of the gradient portion and upper and lower ends has an opening oval been cut horizontally, irregular hearth hopper, characterized in that. 2. A particle discharge pipe, which is provided on a horizontal plate separating the outer hopper and a collecting part, communicates a gap between the outer hopper and a plurality of conduits with the inside of the collecting part, and a lower end of the particle discharge pipe is opened and closed. 2. The modified furnace according to claim 1, further comprising a closing plate, wherein the opening of the closing plate allows particles clogged in a gap between the outer hopper and the plurality of conduits to be discharged into the collecting section. Hopper for bottom. 3. The modified bottom hopper according to claim 1, further comprising an openable / closable manhole for maintaining the inside of the collecting section.