JPH03271607A - Gas-dispersing nozzle for fluidized bed combustion apparatus - Google Patents

Abstract

PURPOSE:To smoothly exhaust gas through gas-dispersing nozzles, and to uniformize the fluidization of mediums to be fluidized, by a method wherein the gas-dispersing nozzles are fitted at an angle smaller than a repose angle of the mediums and on the lower half of each top side thereof, a cut part with a specified length is formed in longitudinal direction. CONSTITUTION:Between water-cooled tubes 56, gas-dispersing nozzles 38, 39 are obliquely fitted at an angle S smaller than a repose angle RA of mediums 28 to be fluidized, and on the lower half of the top side of each of the nozzles, a cut part 50 is formed. By this formation, when exhaust gas burnt in a combustion chamber 2 for primary flow reaches the cut part 50 on the top side of the nozzle 38, the gas flows into the mediums 28 statically laid on a flat plate 57 of the exterior of the nozzle 38, through this cut part and begins to be fluidized because the cut part 50 has area enough of a product of LXC/4, where L is a specified length and C is the circumferential length of the nozzle. With the outflow of the gas, the mediums 28, which enter the inside of the nozzle through the cut part 50, at M, N parts are gradually discharged from the nozzle 38, and the gas is smoothly exhausted from the nozzle 38. In this way, a secondary combustion fluidized-bed 27 is normally formed, and unburnt gas is perfectly burnt.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is a fluidized bed that burns and incinerates high water content wastes (residues) such as beer lees, coffee bean grounds, sludge, etc. that contain a large amount of water. The present invention relates to a gas dispersion nozzle for a fluidized bed combustion device such as a high water content waste incinerator or a fluidized bed boiler that burns fuel such as coal.

[Conventional technology]

As a fluidized bed combustion device, for example, a fluidized bed type high water content waste incinerator is equipped with a primary fluidized combustion chamber in the lower stage, and a secondary fluidized combustion chamber defined by a gas distribution plate in the upper stage,
- Most of the high water content waste such as beer dregs is burned in the secondary flow combustion chamber, and the unburned content (unburned carbon) is introduced from the freeboard through the upper gas distribution plate together with the exhaust gas into the secondary flow combustion chamber. This is where I make sure to burn it completely.

The gas distribution plate is provided with a large number of gas distribution nozzles, and through each gas distribution nozzle, the exhaust gas accompanied by the unburned matter and ash is guided from the primary flow combustion chamber into the secondary flow combustion chamber. It will be destroyed.

[Problem to be solved by the invention]

In this way, gas with ash passes through the gas dispersion nozzle of the gas dispersion plate installed between the secondary flow combustion chamber and the secondary flow combustion chamber, so the ash adheres to the inner surface of the gas dispersion nozzle. This causes a problem in that the gas passage cross section is reduced, the gas flow condition becomes poor, and stable fluidization of the fluidized medium cannot be achieved, making stable fluidized combustion and incineration impossible. In view of this problem, the present applicant has previously formed the gas dispersion nozzle 30 with a straight pipe with low gas passage resistance, as shown in FIG.
Moreover, by attaching this straight pipe to the gas distribution plate at an angle smaller than the angle of repose of the fluidized medium, the gas distribution structure is such that the fluidized medium does not fall downward through the gas distribution nozzle 30 even when the operation is stopped. proposed a nozzle (Utility Application No. 89994/1983).

However, with the gas dispersion nozzle 30 having such a structure, the amount of ash deposited is certainly reduced compared to the conventional one, the operating time can be extended, and even when the operation is stopped, it is possible to prevent the fluid medium from falling downward. However, as shown by the hatched area M in FIG. 6, when the fluid is stopped, the fluid medium is clogged at the tip side of the dispersion nozzle 30 by an amount corresponding to the angle of repose RA of the fluid medium, and the gas or fluid medium is blocked at the tip opening. 30a, the gas temperature is low and the gas flow rate through the gas dispersion nozzle 30 is low, especially during low load such as startup, and the gas flow rate is low due to the small amount of gas, so the gas is dispersed as described above. It is difficult for gas to pass through the part of the tip side of the nozzle 30 where the particle size medium is clogged, or the fluidized medium is difficult to be discharged from the nozzle 30 by the gas flow, and the part where gas easily flows among the many gas dispersion nozzles 30. The fluidized medium in the secondary fluid combustion chamber may not be uniformly fluidized as a whole due to the formation of spots where it is difficult to flow. When the fluidized medium accumulates and forms a mountain, there is no action to break it down, resulting in poor fluidization and the problem that efficient fluidized combustion cannot be performed. Furthermore, when such a phenomenon occurs, ash tends to adhere to the inner surface of the gas dispersion nozzle 30, reducing the passage area, increasing the differential pressure, and at the same time causing a problem that stable fluidization cannot be performed. This problem is not limited to low loads, but even if the load is increased without changing the state, the phenomenon does not subside, and the pressure loss of the gas distribution plate increases, making rated load operation difficult.

The present invention was made in view of such problems,
Even if the gas dispersion nozzle is clogged with fluidic medium at the start of operation, the gas can easily pass through the nozzle, or the fluidic medium can be easily discharged, so that the gas can flow smoothly inside the nozzle even at low loads. A fluidized bed combustion equipment that enables stable operation by ensuring smooth flow and discharge from the nozzle, preventing ash adhesion, and uniform fluidization of the fluidized medium not only at low loads but also at high loads. The purpose is to provide a gas dispersion nozzle.

[Means to solve the problem]

In order to achieve such objects, the present invention (1) is installed in large numbers on the gas distribution plate of a fluidized bed combustion apparatus, and distributes the gas fed from below to the upper part of the gas distribution plate. A gas dispersion nozzle for a fluidized bed combustion apparatus that fluidizes a fluidized medium with a straight pipe, the gas dispersion nozzle being formed with a straight pipe, installed at an angle smaller than the angle of repose of the fluidized medium, and with a tip side of the gas dispersion nozzle. In addition, a cutout portion having a predetermined length in the axial direction is formed in at least a portion of the lower half. (2) A fin is provided on the upper edge of the notch along the axial direction of the gas dispersion nozzle, the fin projecting substantially horizontally.

[For production]

In the gas dispersion nozzle according to claim (1), even if the tip of the gas dispersion nozzle is clogged with the fluidizing medium at the initial stage of operation, the notch is provided in at least a part of the lower half of the nozzle, and the notch is has a predetermined length in the axial direction of the gas dispersion nozzle, so the required gas outflow area leading to the outside of the nozzle is ensured, making it easier for the gas to be discharged. Since the area is large and it is easy to exit to the outside, gas can flow out smoothly from this notch even when the amount of gas at the start of operation is small. The fluid medium is also forced out from this notch and discharged to the outside. In addition,
At this time, by providing the notch in the lower half of the nozzle, the amount of flowing medium flowing into the nozzle is minimized, and the outflow of gas from the notch to the outside is made as easy as possible. . When the operating load is increased, the force of the ejected gas flow causes the fluidized medium entering the nozzle tip opening at the angle of repose needle to be more completely discharged from the notch to the outside of the nozzle. In addition, even if the fluid medium is partially accumulated near the nozzle and a small mountain is formed, the gas will be blown out sequentially from the position where the differential pressure is low in the upper part of the notch, and will continue to blow out to the lower end of the notch, causing a small mountain. I'm going to break it down.

In this way, gas flows smoothly through the gas dispersion nozzle even under low load conditions, uniform fluidization is achieved, ash adhesion is prevented, and stable operation is achieved.

Further, with the configuration as claimed in claim (2), the fins provided in the notch more effectively prevent the fluid medium from entering the notch from the side along the axial direction of the gas dispersion nozzle. This makes it easier for gas to flow out from here, resulting in smoother fluidization.

(Example) First, an example of a fluidized bed type high water content waste incinerator equipped with a gas dispersion nozzle according to an example of the present invention will be described.

FIG. 1 is a schematic longitudinal sectional view of a fluidized bed type high water content waste incinerator.

In Fig. 1, the fluidized bed type high water content waste incinerator has an air chamber 1 located at the bottom stage, a primary fluidized combustion chamber 2 located above it via a gas distribution plate 11, and a separate combustion chamber 2 at the upper stage. A secondary flow combustion chamber 3 is located through an upper gas distribution plate 35.

In the air chamber 1, an auxiliary combustion burner 4 having a combustion air intake lower is attached to the furnace wall. A large number of gas dispersion nozzles 10 are attached to the lower gas dispersion plate 11, and high temperature air in the air chamber 1 is supplied into the primary flow combustion chamber 2 through the gas dispersion nozzles 10.

- In the next fluidized combustion chamber 2, a fluidized medium 14 made of sand such as silica sand having a particle size of III [11 or less] is transferred from the air chamber 1 to the waste dispersion nozzle 1 of the gas distribution plate 11 in the upper part of the gas distribution plate 11.
The primary combustion fluidized bed 15 is fluidized by the high-temperature air dispersed and blown up from zero. The upper part of this secondary combustion fluidized bed 15 is the primary combustion space (freeboard) 1
6. A supply device 32 for supplying beer (wheat) lees (hereinafter sometimes referred to as raw material) as highly water-containing waste is attached to the furnace wall facing the secondary combustion space 16.

Above the primary flow combustion chamber 2 is located the secondary flow combustion chamber 3, defined by a gas distribution plate 55 fitted with gas distribution nozzles 38, 39 according to the invention. In this secondary combustion chamber 3, above the gas distribution plate 55, a secondary combustion fluidized bed 27 is formed of a fluidized medium 28 made of silica sand or the like with a particle size of 1 mm or less, similar to the primary combustion fluidized bed 15. It is fluidized and formed by the combustion exhaust gas from the combustion chamber 2.

The upper part of the secondary combustion fluidized bed 27 is used as a secondary combustion space (free board) 29, and an exhaust gas outlet 31 is provided in the upper part.

In the fluidized bed type high water content waste incinerator configured in this way, combustion air is introduced into the air chamber I from the intake lower,
Fuel such as heavy oil is supplied to the auxiliary combustion burner 4 in the air chamber 1, and the auxiliary combustion burner 4 is operated. This results in 800-10
00°C high-temperature gas is blown up from the gas distribution plate 11 and supplied to the primary combustion chamber 2 to form a primary combustion fluidized bed 15. The temperature of this secondary combustion fluidized bed 15 can be adjusted to, for example, 750°C by controlling the combustion amount of the auxiliary combustion burner 4.
is maintained.

Beer lees as a highly water-containing waste containing, for example, 80% water is passed through the primary combustion space 16 from the raw material supply device 32 disposed on the furnace wall above the secondary combustion fluidized bed 15 to the primary combustion fluidized bed 15. is supplied to When the beer grounds come into contact with the fluidized medium 14 (sand) heated to a high temperature that forms a fluidized bed in the primary combustion fluidized bed 15, the moisture thereof is instantaneously evaporated. In FIG. 1, reference numeral 17 indicates beer dregs as waste that is scattered in the fluidized bed 15 and burned. Beer lees that have lost moisture are easily combusted while being stirred by sand in a fluidized bed. An analysis example of this beer lees shows a higher calorific value of 4850
Kcal/dryness, elemental composition is carbon 48.86%,
Hydrogen 6.91%, oxygen 37.14%, nitrogen 3°23%,
The ash content is 3.28% and the other 0.58%. Approximately 70 to 80% of the beer lees is burned in this secondary combustion fluidized bed 15, and the remaining approximately 30 to 20% of unburned matter (unburnt carbon) is carried along with the combustion gas into the primary combustion space together with ash. 16
The gas then passes through each gas distribution nozzle 38 , 39 of the upper gas distribution plate 55 and is introduced into the secondary flow combustion chamber 3 . At this time, while the unburned matter passes through the primary combustion space 16, a part of it is burned in a high temperature atmosphere. Secondary flow combustion chamber 3
Then, a secondary combustion fluidized bed 27 is formed, and the remaining unburned matter introduced therein is finally combusted and completely combusted.

Combustion exhaust gas at a temperature of 800 to 900°C is discharged from the secondary flow combustion chamber 3 through an exhaust gas outlet 31 and guided to a waste heat boiler (not shown), where the amount of heat is recovered and converted into steam.

The details of the gas dispersion plate 55 as an embodiment to which the gas dispersion nozzles 38 and 39 according to the present invention are attached will be explained in detail in the second embodiment.
It is configured as shown in Figure 4.

The entire structure of the gas distribution plate 55 includes a water-cooled pipe 56, a flat plate (partition plate) 57, and gas distribution nozzles 38 and 39.

That is, the water cooling pipe 56 is connected between a water supply collecting pipe and a discharge collecting pipe (not shown) extending and disposed along both outer side walls 48 of the incinerator main body. A large number of pipes are arranged in parallel at approximately equal intervals in the longitudinal direction and are provided across the furnace, and horizontally adjacent water cooling pipes 56 are connected by a plurality of flat plates 57 (see FIG. 3), and When viewed from above, the outermost water cooling pipe (not shown) and the inner wall surface 47 of the side wall 48 are connected by another flat plate (not shown) to support and fix a large number of groups of upper and lower water cooling pipes 56. .

As shown in FIG. 3, adjacent water cooling pipes 5 in plan view
6 and the water-cooled pipe 56, a water-cooled pipe 56 is inserted through the flat plate 57.
A large number (5 in this embodiment) of gas dispersion nozzles 38.3 according to the embodiment of the present invention are arranged at equal intervals along the longitudinal direction of the
9 are mounted at an angle, and as shown in FIG. Arranged are rows of gas distribution nozzles 39, all tilted in opposite directions. As shown in FIG. 2 or 4, the gas dispersion nozzles 38 and 39 are arranged at an angle S smaller than the angle of repose RA of the fluidized medium 28 of the secondary combustion fluidized bed 27 in the secondary combustion chamber 3 on the upper stage side. It is installed at an angle. This angle of repose RA is approximately 40 degrees for sand and approximately 3 degrees for limestone.
The temperature ranges from 2 to 35 degrees.

Next, the gas dispersion nozzles 38 and 39 will be explained in detail based on FIGS. 1 to 4.

The gas dispersion nozzle 38, 39 has a notch 50 formed in its lower half on the tip side. In this embodiment, the notch 5
0 is a part of the lower half of the gas dispersion nozzle 38 (hereinafter, only the reference numeral 38 will be used for explanation), and is formed over a predetermined length L in the quarter axis direction in the circumferential direction. As shown in FIG. 3, this notch 50 is formed in such a direction that all the nozzles 38 located in a row are directed in the same direction toward the adjacent water cooling pipes 36.

Figure 4 shows one gas dispersion nozzle 38 in Figures 1 to 3.
FIG. 4(A) is a front view, and FIG. 4(B) is a sectional view taken along arrow B in FIG. 4(A). Fourth
In Figure (A), a portion M indicated by solid diagonal lines and a portion N indicated by broken diagonal lines respectively indicate the retention state of the fluidized medium 28 in the gas dispersion nozzle 38 when it is not operating, that is, when it is not fluidized. M indicates a state in which the gas has entered the nozzle 38 from the tip opening 38a of the gas dispersion nozzle 38 at an angle of repose RA, and N indicates a state in which the gas has entered the nozzle 38 from the notch 50. There is. The amount of penetration into the nozzle 38 from the notch 50 can be determined by setting the length of the notch in the circumferential direction to -4/4 of the circumference in the lower half of the nozzle 38, so that the angle of repose can be determined as shown in FIG. 4(B). Due to the RA, it only enters from the upper edge of the notch 50, so it is considered to be small.

In this embodiment, the length L of the notch 50 in the axial direction is the length at which the fluid medium 28 enters the nozzle 38 from the tip opening 38a of the nozzle 38 at an angle of repose RA, that is, the solid hatched portion M in FIG. The length of the base of the triangle shown is considered to be a considerable length. Of course, this length L is longer than this length.
A shorter length closer to the 8a side may also be used. However, even if the length is longer than the length of the angle of repose RA, there is no significant effect. In addition, in the figure, 50a is the formation starting point of the notch 50 in the nozzle axial direction.

In this way, in the situation shown by M and N, the fluid medium 2
When the operation is started from a state in which 8 remains, the combustion exhaust gas from the secondary flow combustion chamber 2 is introduced from the lower end opening of the nozzle 38 and tends to flow toward the tip side. At this time, when the notch 50 on the tip side of the nozzle 38 is reached, the gas is First, the gas flows out from the notch 50 into the fluidized medium 28 placed on the flat plate 57 outside the nozzle 38, and begins to fluidize the fluidized medium 28. The flowing medium 28 in the N section that has entered is gradually discharged to the outside of the nozzle 38. Then, the fluid medium 28 in the M portion that had entered through the front end opening 38a of the nozzle 38 is also gradually discharged from the notch 50 by the force of the gas. This phenomenon becomes more and more complete as the load increases. In this way, the gas can flow smoothly to the nozzle 3.
8, the secondary combustion fluidized bed 27 is normally formed, and the unburned matter is completely combusted here. In this way, the gas flows out smoothly due to the action of the notch 50, so that the adhesion of ash inside the nozzle 38 is drastically reduced, uniform fluidization is performed, and the secondary combustion fluidized bed 27 is stably operated. .

As shown in FIG. 3, in this embodiment, the notches 50 of the nozzles 38 in each row are opened in opposite directions, so that they are perpendicular to the longitudinal direction of the nozzles 38 (the longitudinal direction of the water-cooled pipes 56). The gases are flowed out in the direction (lateral direction), and the outflowing gases collide with each other to promote mixing in the lateral direction.
Since gas flows out from a along the longitudinal direction of the nozzle 38 and in the opposite inclination direction for each row, the gases are mixed also along the longitudinal direction of the nozzle 38, and the gas is mixed only in uneven areas. The fluidization phenomenon is prevented and uniform fluidization is carried out over the entire range of the wide fluidized bed plane, so that the secondary combustion fluidized bed 27
combustion efficiency is improved.

FIG. 5 is a diagram showing another embodiment of the gas dispersion nozzle,
FIG. 5(A) is a front view, and FIG. 5(B) is a sectional view taken along arrow C in FIG. 5(A).

In this embodiment, the upper edge of the notch 50 shown in FIG. 4 along the axial direction of the gas dispersion nozzle 38 [see FIG. 5(B)]
A fin 51 having a required width is attached in the horizontal direction. The end of the fin 51 on the side opposite to the light end opening in the axial direction of the nozzle is extended and positioned further back than the formation starting point 50a of the notch 50.

By doing this, as is clear from FIG. 5(B), the fluid medium 28 is prevented from entering into the nozzle 38 from the notch 50 during non-fluidization when the operation is not performed due to the action of the fins 51. , the gas can flow out more smoothly from this notch 50. Therefore, adhesion of ash is more reliably prevented, and the fluidization of the secondary combustion fluidized bed 27 and its combustion efficiency are further improved. Note that the wider the width of the fins 51 is, the more the nozzle 38 from the notch 50 of the fluid medium 28
It is possible to more reliably prevent intrusion into the interior. Further, in this case, the fluidized medium 28 that remains in the nozzle 38 at the start of operation is only the portion indicated by the solid diagonal line M that enters from the tip opening 38a.

FIGS. 7 to 13 are perspective views showing examples of the notch 50 of the gas dispersion nozzle having various further different shapes.

FIG. 7 shows a case where the notch 50 is formed by cutting out the entire lower half of the tip side of the nozzle 38, so-called halving it. In this way, although a small amount of the fluidizing medium 28 enters from the notch forming starting point 50a, sufficient gas outflow is possible. Further, the cutout portion 50 can be easily formed.

Gas dispersion nozzle 3 in the notch 50 shown in FIG. 7 in FIG.
This figure shows a case in which fins 51 having a required width at the upper edges along the axial direction of the fins 8 are attached horizontally to the upper edges on both sides. In this way, by providing the fins 51 with a required width, it is possible to prevent the fluid medium 28 from entering at all from the notch forming starting point 50a.

FIG. 9 shows a notch formed in the circumferential direction in the same manner as shown in FIG. This figure shows a case where the notch 50 is formed by attaching a shortened flat plate (small piece) 50c facing downward. In this way, it is possible to prevent the fluid medium 28 from flowing into the nozzle 38 from the vicinity of the notch forming point. Note that FIG. 9(A) shows the case where the notch 50 is formed on the front side of the drawing, which is opposite to that of FIG.

In FIG. 10, a notch 50 similar to the embodiment shown in FIG. 7 is formed, and the notch is formed by attaching a plate 50b curved along the arc of the nozzle 38 to the tip of the nozzle 38 by welding or the like. This figure shows a case where a portion 50 is formed.

In this way, the notch can be easily formed. Of course, the plate 50b does not have to be curved, but may be attached as a flat plate to form the notch 50.

FIG. 11 is a perspective view of the gas dispersion nozzle 38 viewed from directly below, and shows a case where a notch 50 is formed by forming an elongated hole at a position directly below the nozzle and closer to the tip opening 38a. In this way, although the width of the notch 50 is reduced, the fluid medium 28 can be prevented from entering the notch 50 by both outer surfaces of the nozzle itself that sandwich the notch.

FIG. 12 is a perspective view of the gas dispersion nozzle 38 seen from directly below, and is a modification of FIG. This figure shows a case in which it is provided and formed.

FIG. 13 shows a case where a lid 50d is attached to the tip opening 38a of the nozzle 38 as a notch 50 similar to that shown in FIG. By providing the lid 50d in this way, it is possible to prevent blow-by due to the gas ejection force during operation.

Note that such a lid 50 is similar to that shown in FIGS. 4 to 12 described above.
They can also be attached to the nozzles 38 shown in the figure.

FIG. 14 shows still another embodiment, in which the protrusion length of the gas dispersion nozzle 38 according to the present invention (the nozzle 38 indicated by a solid line on the left side of the figure) from the flat plate 57 is plotted at two points on the right side of the figure. A case will be described in which the nozzle 38 is provided longer than the conventional nozzle 30 without a notch shown by the chain line so that the upper end opening 38a of the nozzle 38 is closer to the upper surface of the bed on which the fluidized medium 28 is placed. Note that the nozzle 38 is the same as that shown in FIG. 4. The notch 50 is shown formed on the front side of the drawing, which is opposite to that shown in FIG.

In the case of the conventional nozzle 30 without a notch shown on the right side of the figure, when the gas flow rate is low such as during startup, the gas differential pressure inside the nozzle 38 is Because it is smaller than the gas pressure difference passing through the medium 28 (stationary bed), due to the slight difference in height of the stationary bed (the top surface of the stationary bed is undulating), the gas passes through different parts of the fluidized bed. However, by making the nozzle 38 in which the notch 50 is formed in this way longer, the notch 50 is located closer to the tip of the nozzle 30.
Since the gas is ejected from 0, the differential pressure passing through the fluidized medium 28 in the stationary bed can be reduced (the pressure corresponding to the height indicated by Δh in the figure can be reduced), and the gas is distributed more uniformly throughout the nozzle 38. can be made to flow. In the figure, H is the height from the tip opening 30a of the conventional nozzle 30 to the upper surface of the stationary floor, and h is the tip opening 38 of the nozzle 38 of the present invention.
Each represents the height from a to the top surface of the stationary bed.

This is particularly useful when modifying an existing nozzle 30 as shown on the right side of the figure into a nozzle 38 having the notch 5o of the present invention. That is, when a nozzle with a notch 50 formed at the tip of an existing nozzle 30 is joined to form an overall long nozzle 38, when the operating load increases and the gas flow rate increases, the gas flow from the lower end of the notch 50 also increases. Since the gas is ejected, the fluidized range (height) can be maintained at the same height as the conventional nozzle 30.
In addition, since the ejection force of gas from the nozzle tip 38a is weakened, there is an effect that gas blow-by can be reduced.

In this embodiment, the combustion chamber is composed of a primary flow combustion chamber 2 and a secondary flow combustion chamber 3 to perform two-stage combustion. ) can be completely captured and completely combusted, resulting in good combustion efficiency and a blast hearth load of 400 to 450 kg/rW·hr.

Furthermore, compared to an incinerator consisting of a fluidized bed with only one stage, the superficial velocity can be higher, the area of the fluidized bed can be smaller, and the furnace can be made smaller and more compact.

FIGS. 15 to 17 show an embodiment in which the upper gas distribution plate 55 shown in FIGS. 1 to 3 has a different configuration, and the other parts are the same.

In this embodiment, the gas distribution plate 35 is generally composed of an upper water-cooled pipe 36, a lower water-cooled pipe 37, an upper flat plate 42, a lower flat plate 43, and gas distribution nozzles 38, 39.

That is, the upper water cooling pipe 36 and the lower water cooling pipe are spaced vertically between a water supply collecting pipe and a discharge collecting pipe (not shown) which extend and are arranged along both outer side walls 48 of the incinerator main body. A large number of water-cooled pipes 37 are arranged in parallel at approximately equal intervals in the longitudinal direction of the supply water collecting pipe or the discharge collecting pipe, and are provided to cross the inside of the furnace, and the upper water-cooled pipe 36 and the lower water-cooled pipe 37 are respectively arranged in the horizontal direction. The water cooling pipes adjacent to each other are connected by a plurality of upper flat plates 42 and a plurality of lower flat plates 43 (see Fig. 17), and the outermost water cooling pipe (not shown) when viewed from above A large number of upper and lower water cooling pipes 36 are connected to the inner wall surface 47 of the side wall 48 by another flat plate (not shown).
．． The 37th group is supported and fixed. Therefore, the upper and lower flat plates 42
．． 43. Flat plate and water cooling pipe (not shown) 36.37
A portion surrounded by the inner wall surface 47 is a sealed space, and is formed as a compressed gas chamber 45. (See FIG. 16) As shown in FIG. 17, the water cooling pipe 36.
A large number of pipes according to the embodiment of the present invention are inserted between the upper flat plate 42 and the lower flat plate 43 between the water-cooled pipes 36.37 and the water-cooled pipes 36. In this example, five gas distribution nozzles 38, 39 are installed obliquely.

Each gas distribution nozzle 38 , 39 is provided with a compressed gas introduction hole 46 in the pipe wall of the portion located in the compressed gas chamber 45 . Furthermore, an automatic opening/closing valve (not shown) and a compressed gas supply pipe connected to an air tank are attached to the side wall of the compressed gas chamber 45. In addition, the mounting angle, arrangement, etc. of the gas dispersion nozzle are completely the same as in FIGS. 1 to 3.

With the gas distribution plate 35 having such a configuration, compressed air is supplied to the compressed gas chamber 45 during operation or when the operation is stopped, and the compressed gas introduction hole 46 is supplied into the gas distribution nozzle 38.
Since compressed air can be supplied through the nozzle 38 during operation, it is possible to blow away the ash that tends to adhere to the inner surface of the nozzle 38, thereby ensuring that the ash does not adhere to the inner surface of the nozzle 38. The interior of the nozzle 38 can be completely cleaned by blowing out remaining residue such as ash, and the interior of the nozzle 38 can be prepared for the next operation.

Furthermore, in the above embodiments, the fluidized bed combustion apparatus is composed of a primary fluidized combustion chamber 2 and a secondary fluidized combustion chamber 3, and is a fluidized bed injured water-containing waste incinerator that burns and incinerates high water-containing waste. In this case, the present invention provides a fluidized bed combustion apparatus in which -
A fuel such as coal is burned in the secondary fluid combustion chamber 2, and a heat transfer tube is installed here to effectively absorb heat through contact with the fluidized bed. It is also applicable to a fluidized bed boiler in which a desulfurization chamber is configured to form a fluidized bed using a fluidized medium made of a desulfurization agent, and the combustion gas generated in the lower combustion chamber is desulfurized in this desulfurization chamber. I can do it.

In this case, the exhaust gas containing sulfur generated by combustion of coal in the combustion chamber is smoothly introduced into the desulfurization chamber from the gas distribution nozzle 38 not only at low load at the start of operation but also at rated load. Fluidization in the desulfurization bed using ash as a fluidizing medium is performed uniformly, and there is no ash adhesion to the nozzle.
It can perform an efficient desulfurization action.

〔Effect of the invention〕

As is clear from the above explanation, the present invention is based on claim (1).
), even when the amount of gas is small at low loads such as during start-up, the action of the notch allows gas to be smoothly discharged from the gas distribution nozzle, and prevents ash from adhering to the inner surface of the nozzle. Since it is possible to eliminate this, stable and uniform fluidization can be performed not only at low loads but also at high loads. Of course, when the operation is stopped, it is possible to prevent the fluid medium from falling down through the nozzle.

With the structure of claim (2), the gas can be smoothly flowed out from the gas dispersion nozzle, resulting in more stable and uniform fluidization.

[Brief explanation of drawings]

1 to 4 show an embodiment of the present invention,
Fig. 1 is a schematic longitudinal sectional view of a fluidized bed type high water content waste incinerator as a fluidized bed combustion apparatus to which the gas dispersion nozzle according to the present invention is applied, and Fig. 2 is a partial enlargement of the gas dispersion plate in Fig. 1. 3 is a plan view of FIG. 2, and FIG. 4 is an enlarged view of one gas dispersion nozzle.
FIG. 4(A) is a front view, FIG. 4(B) is a sectional view taken along arrow B in FIG. 4(A), and FIG. 5 is a diagram showing another embodiment of the gas dispersion nozzle of the present invention. Figure 5 (A) is a front view, Figure 5 (B)
) is a cross-sectional view taken along arrow C in FIG. 5(A), FIG. 6 is a conventional gas dispersion nozzle, and FIG. 6(A) is a front view;
Figure 6(B) is a cross-sectional view taken along arrow A in Figure 6(A), and Figures 7-
FIG. 14 shows further various different embodiments of the gas dispersion nozzle of the present invention, FIG. 7(A) is a front perspective view of the gas dispersion nozzle, and FIG. 7(B) is a (
8(A) is a front perspective view of the gas dispersion nozzle, and FIG. 8(B) is a side view shown in FIG.
A side view in the direction of arrow E showing only the tip portion of A), FIG. 9(A)
is a front perspective view of the gas dispersion nozzle, FIG. 9(B) is a cross-sectional view taken along arrow F in FIG. 9(A), FIG. 10 is a front perspective view of the gas dispersion nozzle, and FIG. 11 is a view directly below the gas dispersion nozzle. Figure 12 is a view of the gas dispersion nozzle viewed from directly below.
The figure is a front perspective view of a gas dispersion nozzle, FIG. 14 is a front perspective view showing an embodiment in which the gas dispersion nozzle according to the present invention is lengthened and installed in comparison with a conventional nozzle, and FIGS. 15 to 17 are The figures shown in FIGS. 1 to 3 respectively show examples in which the upper gas distribution plate of the present invention has a different configuration, and FIG. 15 shows a fluidized bed type high water content plate. A schematic vertical cross-sectional view of the waste incinerator, FIG. 16 is a partially enlarged front view (partial sectional view) of the gas distribution plate in FIG. 15, and FIG.
FIG. ■... Air chamber, 2... Secondary flow combustion chamber, 3... Secondary flow combustion chamber, 14.28... Fluid medium, 11.35
．． 55... Gas distribution plate, 30.38... Gas distribution nozzle, 38a, 39a... Tip opening, 50... Notch, 51... Fin, RA... Fluid medium repose angle, S
...Gas dispersion nozzle installation angle.

Claims (2)

[Claims] (1) Many are attached to the gas distribution plate of the fluidized bed combustion equipment,
A gas dispersion nozzle for a fluidized bed combustion apparatus that disperses gas fed from below above a gas dispersion plate to fluidize a fluidized medium on the gas dispersion plate, the gas dispersion nozzle being formed by a straight pipe. , the gas dispersion nozzle is attached at an angle smaller than the angle of repose of the fluid medium, and a notch having a predetermined length in the axial direction is formed in at least a part of the distal end side and substantially the lower half of the gas dispersion nozzle. Gas dispersion nozzle for fluidized bed combustion equipment. (2) A gas dispersion nozzle for a fluidized bed combustion apparatus according to claim (1), characterized in that a fin extending substantially horizontally is provided on the upper edge of the notch along the axial direction of the gas dispersion nozzle. .