JP2902627B1 - Combustion flue gas cooling system - Google Patents

Abstract

An object of the present invention is to prevent, in a flue gas temperature reduction device, adhesion and deposition of sticky dust due to water spray in the device while maintaining the temperature reduction performance. SOLUTION: A lower portion has an exhaust gas supply port 12 which opens in a tangential direction of a cylindrical wall, and a cooling exhaust gas outlet 14 is provided at an upper portion.
And an inner cylinder 22 provided concentrically with the outer cylinder such that a space 20 is formed between the outer cylinder and an inner wall of the outer cylinder near the exhaust gas supply port in the outer cylinder. An upper end is provided with an inner cylinder enlarged portion 36 concentrically connected to the inner cylinder, and a cooling water spray nozzle 30 provided in the inner cylinder or the inner cylinder enlarged portion, and extends from the inner cylinder enlarged portion 36 to the outer cylinder 10. In the area,
A cover gas blowing unit is provided for bypassing a part of the exhaust gas and blowing out the cover gas in a sheet form from the gaps 40 and 38 along the inner wall of the inner cylinder enlarged portion 36 and the inner wall of the outer cylinder 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for reducing the temperature of combustion exhaust gas discharged from an incinerator such as a refuse incinerator and other combustion furnaces by spraying cooling water. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion exhaust gas temperature reducing apparatus in which dust is attached and deposited inside by blowing out a sheet-like (screen-like) cover gas.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a conventional combustion exhaust gas temperature reduction apparatus. Reference numeral 10 denotes an outer cylinder. An exhaust gas supply port 12 which opens in a tangential direction of the cylinder wall is provided at a lower portion of the outer cylinder 10, and a cooling exhaust gas outlet 14 is provided at an upper portion.
A settling dust discharge port 18 for discharging the settling dust 16 is provided at a lower portion of the outer cylinder 10. 19
Is a hopper section. In the outer cylinder 10, an inner cylinder 22 is disposed concentrically with the outer cylinder 10 near the exhaust gas supply port 12 so that a space 20 is formed between the outer cylinder 10 and the inner wall of the outer cylinder 10. At the upper end, a hollow substantially inverted truncated conical inner cylinder enlarging portion 24 is connected concentrically with the inner cylinder. The upper part of the inner cylinder enlarged part 24 and the inner wall of the outer cylinder 10 are in contact with each other, so that exhaust gas does not flow between the inner cylinder enlarged part 24 and the outer cylinder inner wall. In the outer cylinder 10, an evaporating section 26 as an evaporating space is provided above the inner cylinder enlarging section 24. Further, a cooling water spray nozzle 30 is provided in the vicinity of the connection between the inner cylinder 22 and the inner cylinder enlarged portion 24.

As a prior art, Japanese Utility Model Laid-Open Publication No. Hei 6-65728 discloses an upper chamber into which combustion exhaust gas is introduced, and a partition plate having an opening to separate the upper chamber from the upper chamber. A lower chamber for mixing exhaust gas with water sprayed from a nozzle, and guide vanes disposed at the opening, wherein a partition plate is formed by a perforated plate, and the guide vanes are configured to have a variable pitch angle. A combustion flue gas cooling device is described. Also, Japanese Patent Application Laid-Open No. 9-33
No. 032 discloses a gas supply port in which an inner cylinder is concentrically arranged inside a lower side of an outer cylinder and communicates with a gap formed between the outer cylinder and the inner cylinder and opens in a tangential direction of the cylinder wall. Provided, a guide cylinder consisting of an introduction section and a heat retaining section continuously provided at the upper end of the inner cylinder,
The introduction part is formed in a shape that expands in diameter upward from the upper edge of the inner cylinder, and the heat retaining part is formed in a straight body shape that extends upward from the upper edge of the introduction part. There is described a low-temperature gas cooling tower in which a bottleneck is formed in communication with the gap and an upper end of the bottleneck and a lower end of the gap are formed as open ports.

[0004]

The dust content accompanying the flue gas is relatively small in particle size and specific gravity and has little adhesion. However, when moisture is contained by water spray, the specific gravity is reduced. Becomes large, the inertial force due to the turning increases, and at the same time, the adhesive force increases due to the stickiness, so that it is easy to collide with and adhere to the wall surface. In the conventional flue gas temperature reduction device as shown in FIG. 5, when a large amount of dust is contained in the flue gas, as shown in FIG. The so-called dust trouble occurs in which wet dust adheres to the inner wall of the device 26 and the dust adheres and accumulates in an apparatus other than the hopper. 32 and 34 are adhesion dust.

[0005] The flue gas temperature reducing device described in Japanese Utility Model Application Laid-Open No. 6-65728 is aimed at preventing dust from adhering and accumulating in the device (dust free). It is fundamentally different from the invention. Also,
In the low temperature range gas cooling tower described in Japanese Patent Application Laid-Open No. 9-33032, a water spray contains water and becomes tacky,
In addition, there is a problem that the dust having the increased specific gravity collides with the inner wall of the introduction section corresponding to the enlarged cylindrical section and the inner wall of the heat retaining section corresponding to the evaporating section and adheres and accumulates.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a sheet-like (screen) along an inner wall by bypassing a part of exhaust gas in a region from an enlarged portion of an inner cylinder to an outer cylinder. Shape) as a cover gas,
The cover gas prevents the moist dust from directly colliding with the inner wall. As a result, the dust adheres to the inner wall of the inner cylinder enlarged portion and the inner wall of the evaporating portion as seen in the conventional apparatus shown in FIG. It is an object of the present invention to provide a combustion exhaust gas temperature reducing device that prevents accumulation and maintains the temperature reducing performance.

[0007]

In order to achieve the above-mentioned object, a combustion exhaust gas cooling apparatus of the present invention has an exhaust gas supply port which opens in a tangential direction of a cylindrical wall at a lower side, and an upper part of the apparatus. An outer cylinder having a cooling exhaust gas outlet, an inner cylinder provided concentrically with the outer cylinder so that a space is formed between the outer cylinder and an inner wall near the exhaust gas supply port in the outer cylinder; An inner cylinder enlarged portion concentrically connected to the inner cylinder at the upper end thereof, and a cooling water spray nozzle provided in the inner cylinder or the inner cylinder enlarged portion,
In a region from the inner cylinder enlarged portion to the outer cylinder, cover gas blowing means is provided to bypass a part of the exhaust gas and blow out as a cover gas in a sheet shape along the inner cylinder enlarged portion inner wall and the outer cylinder inner wall. (See FIGS. 1 to 3).

Further, the combustion exhaust gas temperature reducing apparatus of the present invention has an exhaust gas supply opening which opens in a tangential direction of a cylinder wall at a lower portion, and an outer cylinder having a cooling exhaust gas outlet at an upper portion, and the outer cylinder. In the vicinity of the exhaust gas supply port, an inner cylinder provided concentrically with the outer cylinder so that a space is formed between the inner cylinder and the inner cylinder, and an inner cylinder concentrically connected to the upper end of the inner cylinder at the upper end of the inner cylinder. A cylinder enlargement portion, comprising a cooling water spray nozzle provided in the inner cylinder or the inner cylinder enlargement portion, and providing a circular exhaust gas blowing gap between the upper portion of the inner cylinder enlargement portion and the outer cylinder inner wall. The inner cylinder enlarged portion is divided into a plurality of stages in the horizontal direction, and the ends of each of the divided inner cylinder enlarged divided portions are placed on top of each other so that the exhaust gas flows from the outside to the inside. It is characterized by forming a circular exhaust gas blowing gap by overlapping so that And has (see FIGS. 1 to 3).

In this apparatus, part of the exhaust gas is supplied to the sheet-like rising flow without swirling flow in the exhaust gas blowing gap of the inner cylinder enlarged portion and the exhaust gas blowing gap between the inner cylinder enlarged portion and the outer cylinder inner wall. It is preferable to provide a rectifying member for blowing out (see FIG. 3). In this case, the rectifying member
Although it is preferable to use a rectifying member that also serves as a structural member such as a spacer (see FIG. 3), it is also possible to separately provide a structural member such as a spacer and a rectifying member. Further, in these devices, there is a case where a variable-type turning adjustment blade for adjusting the turning force of the exhaust gas is provided in the inner cylinder (see FIG. 4).

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is not limited to the following embodiments, but can be implemented with appropriate modifications. FIG. 1 shows a flue gas cooling device according to a first embodiment of the present invention, and FIG.
FIG. 3 schematically shows an example of a cover gas blowing means which is a portion surrounded by a chain line in FIG. An exhaust gas supply port 12 that opens toward the tangential direction of the cylinder wall is provided on the lower side of the outer cylinder 10, and a cooling exhaust gas outlet 14 is provided above the outer cylinder 10. A hopper 19 is provided at a lower portion of the outer cylinder.
Settling dust outlet 1 for discharging settling dust 16
8 are provided. An opening / closing means (not shown) such as a shutter and a valve is provided below the settling dust discharge port 18. When the opening / closing means is opened, the settling dust is discharged.

In the outer cylinder 10, an inner cylinder 22 is disposed concentrically with the outer cylinder 10 near the exhaust gas supply port 12 so as to form a space 20 between the outer cylinder 10 and the inner wall of the outer cylinder 10. At the upper end of the tube 22, a hollow substantially inverted truncated conical inner tube enlarged portion 36 is connected concentrically with the inner tube. Further, a cooling water spray nozzle 30 is disposed inside the vicinity of the connection between the inner cylinder 22 and the inner cylinder enlarged portion 36.

As shown in FIG. 1 and FIG.
A circular exhaust gas blowing gap (slit) 38 is provided between the upper part of the cylinder 6 and the inner wall of the outer cylinder 10. Further, the inner cylinder enlarged portion 36 is divided into a plurality of stages in the horizontal direction, for example, in this embodiment, divided into two stages, and an upper large-diameter inner cylinder enlarged divided portion 36a and a lower small-diameter inner cylinder enlarged divided portion 36a. 36b. Then, the divided inner cylinder enlarged dividing section 3 is divided so that the exhaust gas flows from the outside to the inside of the inner cylinder enlarged section 36.
6a and 36b, the lower end of the upper large-diameter inner cylinder enlarged division 36a is connected to the lower small-diameter inner cylinder enlarged division 36.
A circular exhaust gas blowing gap (slit) 40 is formed so as to overlap the upper side of the upper end of b. Further, the exhaust gas blowing gap 40 and the exhaust gas blowing gap 38 between the inner cylinder enlarged portion and the outer cylinder inner wall are provided.
A plurality of rectifying members 42 and 44, for example, rectifying plates, for blowing a part of the exhaust gas as a sheet-like (screen-like) upward flow having no swirling flow are fitted. These rectifying members 42 and 44 also serve as structural members such as spacers for forming the gaps 40 and 38 and maintaining strength.

In the flue gas temperature reducing apparatus configured as described above, for example, the flow rate from the exhaust gas supply port
Most of the exhaust gas at about 50 to 300 ° C. flows from the lower part of the inner cylinder 22 while turning, and the cooling water spray nozzle 30
After the temperature of the cooling water is reduced to, for example, about 150 ° C. by the latent heat of evaporation of the cooling water sprayed from the cooling water, the cooling water is discharged from the cooling exhaust gas outlet 14. The inner cylinder enlarged portion 36 and the gaps 40 and 38 are provided between the inner cylinder enlarged portion 36 and the outer cylinder 10, respectively.
A part of the exhaust gas flowing from
The gas is blown from 0 and 38 as a screen-shaped cover gas. Rectifying members (for example, rectifying plates) 42, 44 which are also structural members are provided in the exhaust gas blowing gaps 40, 38, and cover gas is formed in a sheet-like swirling flow along the inner cylinder enlarged portion or the inner wall surface of the outer cylinder. There is no upward flow.

As shown in FIG. 3, the wet dust 46 increases the inertial force due to the centrifugal force caused by the turning, and tries to collide with the inner wall surface of the inner cylinder enlarged portion 36 and the inner wall surface of the outer cylinder 10. The cover gas, which rises immediately above, changes the direction of the wet dust 46 in the downstream direction (upward) of the flow so as not to approach the wall surface, and prevents the collision of the wet dust 46 with the wall surface. Dry the wet dust.
As a result, adhesion of dust to the wall surface is prevented.

FIG. 4 shows a combustion exhaust gas temperature reducing apparatus according to a second embodiment of the present invention. In this embodiment, the inner cylinder 2
2, a variable swirling adjusting blade 48 for adjusting the swirling force of the exhaust gas is provided, for example, at a lower portion in the inner cylinder 22. In the present embodiment, the swirl force of the exhaust gas is appropriately adjusted by changing the angle of the blade, the evaporation of the spray water droplets and the mixing of the gas are optimally maintained with respect to the operating conditions (for example, the exhaust gas flow rate), and the temperature reduction performance is constantly maintained. Can be kept high.
Other configurations and operations are the same as those in the first embodiment.

[0016]

As described above, the present invention has the following effects. (1) In a region from the inner cylinder enlarged portion to the outer cylinder, a part of the exhaust gas is bypassed and blown out as a cover gas along the inner wall in a sheet shape (screen shape). This prevents moisture-laden dust from directly colliding with the inner wall, and reliably prevents dust from adhering and accumulating on the inner wall of the inner cylinder enlarged portion and the outer cylinder inner wall while maintaining the temperature reducing performance. . (2) In the case where the flow regulating member is provided in the gap for blowing the cover gas, the cover gas becomes an upward flow without a swirling flow along the wall surface, and the adhesion and accumulation of dust on the inner wall can be more reliably prevented.

[Brief description of the drawings]

FIG. 1 is a schematic configuration perspective view showing a flue gas temperature reducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG.

FIG. 3 is a schematic view of a portion surrounded by a chain line circle in FIG.

FIG. 4 is a schematic configuration perspective view showing a flue gas temperature reducing apparatus according to a second embodiment of the present invention.

FIG. 5 is a schematic configuration perspective view showing an example of a conventional flue gas temperature reduction device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Outer cylinder 12 Exhaust gas supply port 14 Cooling exhaust gas outlet 16 Sedimentation dust 18 Sedimentation dust discharge port 19 Hopper part 20 Space 22 Inner cylinder 24, 36 Inner cylinder enlarged part 26 Evaporation part 30 Cooling water spray nozzle 32, 34 Adhered dust 36a Large diameter Inner cylinder enlarged dividing section 36b Small diameter inner cylinder enlarged dividing section 38, 40 Exhaust gas blowing gap 42, 44 Rectifying member 46 Wet dust 48 Swirling adjustment blade

Continuation of the front page (72) Inventor Atsushi Mizobata 1-3-1 Higashikawasaki-cho, Chuo-ku, Kobe Kawasaki Heavy Industries, Ltd. Kobe Head Office (56) References JP-A-9-33032 (JP, A) JP-A-10 −24212 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F23J 15/00 F28C 3/08 B01D 51/00 F23L 17/00 F23L 17/14 F23G 5/44

Claims (5)

(57) [Claims] 1. An outer cylinder having an exhaust gas supply port which opens in a tangential direction of a cylinder wall on a lower side and a cooling exhaust gas outlet on an upper part, and an outer cylinder in the outer cylinder near an exhaust gas supply port. An inner cylinder provided concentrically with the outer cylinder so that a space is formed between the inner cylinder and the inner cylinder; an inner cylinder enlarged portion concentrically connected to the upper end of the inner cylinder with the inner cylinder; A cooling water spray nozzle provided in the cylinder enlargement portion, in a region from the inner cylinder enlargement portion to the outer cylinder, a part of the exhaust gas is bypassed to form a sheet along the inner cylinder enlargement portion inner wall and the outer cylinder inner wall. A flue gas temperature reducing device provided with a cover gas blowing means for blowing as a cover gas. 2. An outer cylinder having an exhaust gas supply port which opens in a tangential direction of the cylinder wall at a lower portion, and an outer cylinder having a cooling exhaust gas outlet at an upper part thereof. An inner cylinder provided concentrically with the outer cylinder so that a space is formed between the inner cylinder and the inner cylinder; an inner cylinder enlarged portion concentrically connected to the upper end of the inner cylinder with the inner cylinder; A cooling water spray nozzle provided in the enlarged tube portion, and a circular exhaust gas blowing gap is provided between the upper portion of the enlarged inner tube portion and the inner wall of the outer tube. Divided into multiple stages, and the ends of each divided inner cylinder enlarged division are overlapped so that the large-diameter inner cylinder enlarged division is on the upper side, so that the exhaust gas flows from the outside to the inside, and it is a circular shape. A flue gas temperature reducing device, wherein a flue gas blowing gap is formed. 3. A part of the exhaust gas is blown out as a sheet-shaped rising flow without a swirling flow into the exhaust gas blowing gap of the inner cylinder enlarged portion and the exhaust gas blowing gap between the inner cylinder enlarged portion and the outer cylinder inner wall. 3. The flue gas temperature reducing device according to claim 2, further comprising a rectifying member for causing the exhaust gas to cool. 4. The flue gas cooling device according to claim 3, wherein the rectifying member is a rectifying member that also serves as a structural member such as a spacer. 5. The flue gas temperature reducing apparatus according to claim 1, wherein a variable swirl adjusting blade for adjusting the swirling force of the exhaust gas is provided in the inner cylinder.