JPH07190301A - Boiler - Google Patents

Abstract

PURPOSE:To provide a compact boiler which has a large steam separating surface, can obtain steam of high dryness and high quality and has a small occupied area and a simple structure. CONSTITUTION:The boiler comprises an annular water header 21 having a water tube wall 21 formed of water tubes 19 connected via fins 19a in a cylindrical shape and provided at its lower end with a feed water tube 21a, an annular outer header 22 provided at an upper end, and an air dispersing plate 23 horizontally arranged on an inner periphery of the header 21. The boiler further comprises a cylindrical fluidized bed boiler body 27 having a combustion chamber 26 which has a wind box 25 formed at a lower side of the plate 23 and a fluidized bed part 28 and a free board 29 formed at an upper side of the plate 23, and a smoke tube boiler 36 arranged at an upper part of the body 27 and having a plurality of smoke tubes 35 vertically extended and communicating with the chamber 26 in a vessel 32, wherein the header 22 communicates with the vessel 32 via a communicating tube 37, and the vessel 32 communicate with the header 21 by a return tube 38.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boiler in which a fluidized bed boiler body and a smoke tube boiler are combined.

[0002]

2. Description of the Related Art In factories, etc., incinerate industrial waste such as styrofoam, coffee grounds, and wood chips, and at the same time generate steam by using the heat, and use this steam as a power source or heat source. Is being considered.

However, the industrial waste is non-uniform as a fuel because it may be mixed with flame-retardant or non-combustible foreign matter or may contain a large amount of water. When incinerating industrial waste to produce steam, a fluidized bed boiler is suitable from the viewpoint of effective combustion.

FIG. 2 shows an example of this type of boiler. A water pipe wall 2 having front and rear side faces and an upper face formed by water pipes 1 connected to each other by fins 1a, and an inner lower portion of the water pipe wall 2 are shown. And an air distribution plate 5 provided in the horizontal direction, and a wind box 4 provided below the air distribution plate 5 and provided with a combustion air inlet 3.
And a combustion chamber 9 formed above the air dispersion plate 5 constitute a fluidized bed boiler body 10.

A bed material (sand or the like) is charged into the combustion chamber 9 and the fluidized bed portion 7 is formed by jetting air from the air dispersion plate 5. In the figure, reference numeral 8 is a freeboard portion formed on the upper side of the fluidized bed portion 7, reference numeral 6 is a waste supply hole for penetrating the water pipe wall 2 to input industrial waste from the outside from the side, and reference numeral 2a is the water pipe 1. Water supply header provided at the bottom of the
b shows the steam header provided on the upper part.

In the wake of the fluidized bed boiler body 10,
A boiler bank 16 for heat recovery is integrally provided.
The boiler bank is provided with a hot gas duct 11 separated from the fluidized bed section 7 and the freeboard section 8 by a wall surface formed by vertically extending water pipes 1 connected to each other by fins 1a. A gas introduction portion 17 communicating with an upper position of the freeboard portion 8 of the fluidized bed boiler 10 is formed at the upper end, and a gas discharge portion 18 is formed at the lower end of the other side portion. The gas introducing portion 17 and the gas discharging portion 18 are formed by the water pipes 1 which are not connected to each other by the fins 1a, and a gap is provided between the water pipes 1.

At the lower end of the boiler bank 16 is provided a large-diameter water drum 12 communicating with the water supply header 2a, and at the upper end of the boiler bank 16, communicating with the steam header 2b and the ceiling water pipe 1. Large diameter steam drum 1
4 is provided, and a large number of water pipes 15 connecting the water drum 12 and the steam drum 14 are arranged in the high temperature gas duct 11. Reference numeral 14a denotes a steam separation surface formed in the steam drum 14.

In the conventional boiler shown in FIG. 2, the air supplied from the combustion air inlet 3 to the wind box 4 is
The bed material is supplied to the fluidized bed portion 7 through the air dispersion plate 5 to form a fluidized bed, and the bed material is fluidized and fluidized and burned so as to obtain a good mixture with the industrial waste introduced through the waste material supply hole 6. Done.

Combustion gas generated by fluidized combustion rises in the freeboard portion 8 and enters the high temperature gas duct 11 through the gap of the gas introduction portion 17, and further descends in the gas duct 11 to the outside through the gap of the gas discharge hole 18. Is discharged to. At this time, the water supplied to the water drum 12 is transferred to the boiler bank 16
Since the water in the water pipe 15 flows upward in the water pipe 15, the water in the water pipe 15 is heated by the heat of the combustion gas, a part of the water becomes steam, and the steam is separated in the steam drum 14. Further, since water is flowing upward in the water pipe 1 of the water pipe wall 2 forming the side surface and the upper surface of the fluidized bed boiler body 10, the water is heated by the heat of fluid combustion in the fluidized bed boiler body 10. A part of it becomes steam, and this steam is also stored in the steam drum 14, and the steam in the steam drum 14 is supplied to the outside via the steam discharge pipe 13.

[0010]

However, when industrial waste is used as the fuel for the conventional boiler, the industrial waste is heterogeneous as a fuel as described above, and the shape and calories during combustion are high. Etc., the amount of heat generated by combustion always changes, and the fluidized bed boiler body 1
At 0, it was difficult to stably obtain high-quality steam with stable pressure and high dryness.

That is, the steam generated in the fluidized bed boiler body 10 and the boiler bank 16 is separated and taken out by the steam / water separation surface 14a of the steam drum 14, but the conventional boiler has a total cross-sectional area of the water pipes 1 and 15. On the other hand, the area of the air-water separation surface 14a is relatively small, and therefore the air-water separation is not sufficiently performed, and it is easy to be supplied as moist steam. A change in the amount changes the amount of steam generated, and a change in the level of the steam separation surface 14a (steam drum 1
The area of the air / water separation surface 14a changes (depending on the shape of 4),
This causes a problem that the dryness (wetness) of the steam also changes.

As a method for solving this problem, it is conceivable to increase the diameter of the steam drum 14 to increase the area of the steam / water separating surface 14a. However, in the boiler of FIG. Therefore, it is necessary to separately provide a large steam drum 14, and since the boiler bank 16 is provided at the downstream of the gas of the fluidized bed boiler body 10, the width dimension of the boiler becomes large, and There is a problem that the occupied area becomes large, and further, there is a problem that the apparatus becomes unstable due to the large and heavy steam drum 14 being provided at an offset position above the boiler.

Further, in the conventional boiler, in order to supply water to the water pipes 1 and 15, the water supply header 2a and the water drum 12 are provided.
In addition, the steam header 2b is required, and in combination with the existence of the steam drum 14, the structure of the entire boiler is complicated.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a small-sized boiler which can always obtain a high-quality steam having a high degree of dryness and has a simple structure and is compact.

[0015]

In the boiler of the present invention, water tubes arranged so as to extend in the vertical direction are connected to each other by fins to form a tubular water tube wall, and the water tube wall has a lower end at the lower end thereof. An annular water header is provided along the water pipe wall, an outlet header is provided at the upper end of the water pipe wall along the water pipe wall, and an air dispersion plate is horizontally provided on the inner surface side of the annular water header. A plurality of air chambers, which are arranged below the air distribution plate, form a wind box, and which extend vertically and communicate with the combustion chamber above the fluidized-bed boiler main body having a combustion chamber formed above the air distribution plate. A smoke tube boiler having a smoke tube in a container is disposed, the outlet header is connected to the smoke tube boiler container through a communication pipe, and the container is communicated with the annular water header through a return pipe. It is a thing.

[0016]

In the boiler of the present invention, the smoke tube boiler is disposed above the fluidized bed boiler main body, and the steam generated in the fluidized bed boiler main body is introduced into the container of the smoke tube boiler through the communicating pipe. Air / water is separated by a large air / water separation surface, and even if the calorific value changes and the level of the air / water separation surface changes, the area of the air / water separation surface does not change, so the dryness is always high. Steam is obtained stably.

Furthermore, since the smoke tube boiler is arranged above the fluidized bed boiler, the occupied area when the boiler is installed can be reduced and the stability of the entire apparatus can be improved, and the entire boiler can be simplified. Can have a different structure.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the boiler of the present invention, in which water tubes 19 arranged so as to extend in the vertical direction are connected to each other by fins 19a to form, for example, a cylindrical water tube wall 20. An annular water header 21 provided at the lower end of the water pipe wall 20, an annular outlet header 22 provided at the upper end of the water pipe wall 20, and an inner peripheral surface of the annular water header 21. The air distribution plate 23 arranged horizontally, the wind box 25 formed below the air distribution plate 23, and the air distribution plate 2
A fluidized bed boiler main body 27 is constituted by the combustion chamber 26 formed on the upper side of 3. In the figure, 21a is an annular water header 2
Reference numeral 24 is a water supply pipe attached to 1, and reference numeral 24 is a combustion air inlet provided in a wind box 25.

A bed material is loaded into the combustion chamber 26, and air is ejected from the air dispersion plate 23 to form a fluidized bed portion 2.
8 is formed. Further, in the figure, reference numeral 29 is a freeboard portion formed above the fluidized bed portion, and 30 is the water pipe wall 2.
The figure shows an industrial waste supply hole that penetrates 0 to input industrial waste from the outside from the side.

An outer periphery of the fluidized bed boiler main body 27 is surrounded by a heat insulating material 31, and the fluidized bed boiler main body 27 is surrounded.
A cylindrical container 32 having substantially the same diameter as
Of the steam exhaust pipe 33, a gas exhaust portion 34 provided around the steam exhaust pipe 33, and a bottom end extending vertically inside the container 32 and penetrating the bottom of the container 32. The gas discharge part 3 communicates with the combustion chamber 26 and has an upper end.
A smoke tube boiler 36 constituted by a smoke tube 35 communicating with 4
Is provided.

Further, a communication pipe 37 which communicates between the outlet header 22 and a substantially middle portion in the vertical direction of the water portion of the container 32, and a lower portion of the water portion of the container 32 and the water supply pipe 21a are connected. A return pipe 38 communicating therewith is provided. Further, reference numeral 39 in the figure denotes a steam separation surface formed in the container 32.

Next, the operation of the above embodiment will be described.

In the boiler of this embodiment, the air supplied from the combustion air inlet 24 to the wind box 25 is the air dispersion plate 2
3 is supplied to the fluidized bed section 28 to form a fluidized bed. At the same time, when industrial waste is introduced from the waste supply hole 30, it mixes with the bed material and fluidizes and burns.

The combustion gas generated by the combustion of the combustible gas and the solid fuel volatilized in the combustion chamber 26 rises in the freeboard section 29, reaches the upper part of the fluidized bed boiler main body 27, and reaches the upper end of the smoke tube 35 to form the smoke tube. 35, flows upward, is collected in the gas discharge part 34, and is discharged into the discharge pipe 34a.
Emitted from. When a material having a desulfurizing action such as limestone is used for the bed material, the sulfur oxides in the combustion gas undergo a reducing action.

At this time, since water is supplied from the water supply pipe 21a into the water pipe 19 through the annular water header 21 so that the water flows upward in the water pipe 1, it flows in the water pipe 19. The water is evaporated by the heat generated by the fluidized combustion in the fluidized bed boiler main body 27 to form a mixture of air and water, which rises in the water pipe 19 and is collected in the outlet header 22. Furthermore, the water passes through the communication pipe 37 and the smoke pipe boiler 36. It is sent into the container 32. The combustion gas flowing from the freeboard portion 29 into the smoke pipe 35 also heats the water in the container 32 of the smoke pipe boiler 36 to generate steam. The steam in the container 32 is separated by the steam separation surface 39 to become dry steam, which is taken out from the steam discharge pipe 33.

In the boiler of this embodiment, since the smoke tube boiler 36 is arranged above the fluidized bed boiler main body 27, a large steam separation surface 39 formed in the container 32 of the smoke tube boiler 36 is used. As a result, the steam generated in the fluidized bed boiler main body 27 can be sufficiently separated into steam and water, and thus steam with a high dryness can always be stably obtained.

Further, since the smoke tube boiler 36 has a vertically long cylindrical shape, even if the amount of steam generated fluctuates due to a change in the amount of heat generation and the level of the steam-water separation surface 39 changes, the steam-water separation surface is also changed. Since the area of 39 does not fluctuate, it is possible to stably obtain a vapor having a high degree of dryness.

Further, when the smoke tube boiler 36 is disposed above the fluidized bed boiler main body 27, the occupied area at the time of installing the boiler is only the occupied surface of the fluidized bed boiler main body 27, so that the occupied space of the boiler is reduced. In addition, since the imbalance of weight does not occur, the stability of the apparatus can be improved, and the boiler main body can have a very simple structure.

Therefore, it is possible to provide a small-sized boiler having a simple structure and a compact structure, which can always obtain high-quality steam having a high degree of dryness.

In the embodiments of the present invention, the fluidized bed boiler main body and the smoke tube boiler have been described as having a cylindrical shape. However, the present invention can be performed with an elliptical shape, a polygonal shape, and the like, and other points of the present invention. It goes without saying that various changes can be made without departing from the above.

[0032]

In the boiler of the present invention, the smoke tube boiler is arranged above the fluidized bed boiler body, and the steam generated in the fluidized bed boiler is introduced into the container of the smoke tube boiler through the communicating pipe. Therefore, even for steam whose dryness is unstable from the fluidized bed boiler, it is possible to always obtain stable steam with a high dryness by using the large steam separation surface of the smoke tube boiler, and the calorific value changes. Then, even if the level of the air / water separation surface changes, the area of the air / water separation surface does not change, so that it is possible to always stably obtain a dry steam.

Further, since the smoke tube boiler is disposed above the fluidized bed boiler, the occupied area when the boiler is installed can be reduced and the operational stability of the entire apparatus can be improved, and the boiler can be improved. The entire structure can be made simple.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a boiler of the present invention.

FIG. 2 is a vertical sectional view showing an example of a conventional boiler.

[Explanation of symbols]

 19 Water Pipe 19a Fin 20 Water Pipe Wall 21 Annular Water Header 21a Water Supply Pipe 22 Outlet Header 23 Air Dispersion Plate 25 Air Box 26 Combustion Chamber 27 Fluidized Bed Boiler Main Body 28 Fluidized Bed Section 32 Container 35 Smoke Tube 36 Smoke Tube Boiler 37 Communication Tube 38 Return tube

Claims (1)

[Claims] 1. A tubular water pipe wall is formed by connecting fins between water pipes arranged so as to extend in the vertical direction, and an annular shape is formed at the lower end of the water pipe wall along the water pipe wall. A water header is provided, an outlet header is provided at the upper end of the water pipe wall along the water pipe wall, and an air distribution plate is horizontally arranged on the inner surface side of the annular water header. Form a wind box on the side,
A smoke tube boiler having a plurality of smoke tubes extending in the vertical direction and communicating with the combustion chamber is provided in the upper part of a fluidized-bed boiler body having a combustion chamber formed above the air dispersion plate, and the outlet header is provided. Is connected to the container of the smoke tube boiler via a communication pipe, and the container is connected to the annular water header via a return pipe.