JPH08121740A - Soot blower - Google Patents

Abstract

PURPOSE: To produce a cleaning force by an injection pipe itself and to contribute the energy saving. CONSTITUTION: A soot blower is provided with the supplying mechanism of fluid, at least one set of injection pipe 22, connected to the supplying mechanism and arranged so as to be intersected with a heat transfer tube 10, and at least one set of injection port 13, bored in the lengthwise direction of respective injection pipes 22 to inject the fluid. Respective injection pipes 22 are provided with a cleaning assisting mechanism, disturbing the flow of combustion gas which flows into the intersecting direction with the heat transfer tubes 10, while the cleaning assisting mechanism are provided with a square configuration, formed in the lengthwise direction of respective injection pipes 22. According to this method, the adhesion of dust is reduced by the flow of combustion gas, which is collided against the injection pipe and disturbed, whereby the frequency of steam injection is reduced and the energy saving can be achieved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cleaning heat transfer tubes arranged in a waste heat boiler, a small boiler, etc., and particularly to improve the cleaning power of an injection tube arranged in a direction intersecting with a combustion gas flow. It relates to a suitable soot blower.

[0002]

2. Description of the Related Art FIG. 11 shows a conventional sootblower.
Also, a stationary rotary sootblower as shown in FIG. 12 is known. A supply mechanism for a fluid such as steam, at least one cylindrical injection pipe 12 connected to the supply mechanism and arranged so as to intersect with the heat transfer pipes 10, and each injection pipe 12 is bored in the length direction. A sootblower having at least one injection hole 13 for ejecting a fluid, wherein the supply mechanism is composed of the following parts, and the rotation of the gamault 1 is transmitted to the spur gear wheel 3 that meshes with the pinion 2, and the spur gear wheel 3 is used. Swivel tube 4 fixed with a key
To rotate. The swivel tube 4 rotates the injection pipe 12 connected via the coupling 6. The steam as the injection medium enters the injection pipe 12 from the steam pipe 8 via the gooseneck 7 and the swivel tube 4 and is ejected from the injection hole 13. Immediately after the connection of the gooseneck 7 to the steam pipe 8, a valve is built in, and its valve rod is mechanically operated by a cam attached to the spur gear wheel 3.
The sootblower body is assembled to the wall box 5 provided on the side wall 9, and the injection pipe 12 is supported by the injection pipe support 11 attached at an appropriate interval in the length direction of the boiler tube (heat transfer pipe) 10 to form a porous body. In the formula, the injection holes 13 are provided in one row or in a staggered arrangement in the length direction. When the operation of the soot blower starts, the injection pipe 12 rotates to eject the steam from the injection hole 13, and the dust adhering to the boiler tube 10 is removed by the steam jet and the turbulence of the combustion gas due to the steam jet. Usually, the injection pipe 12 is installed in a relatively low temperature region where it can be exposed to the combustion gas without a cooling medium. The injection holes 13 are also arranged between the rows of the boiler tubes 10 and do not directly inject steam toward the boiler tubes 10 in order to prevent damage to the boiler tubes 10. Further, since the number of the injection holes 13 is large, the diameter of each injection hole 13 is set to a small value of about φ5 mm to φ8 mm, so that the ejection amount per one is small and the cleaning power is also small. However, because of the large number of injection holes, the ejection amount per unit time is 5000 when one soot blower is operated, though it is a short time.
Since a large amount of steam of Kg / Hr or more is required, a capacity shortage occurs when using self-steam in a small package boiler or waste heat boiler. Further, since the injection pipe is a round pipe, it takes a lot of time to attach and process the injection hole.

13 to 15 are prediction diagrams of the combustion gas flow with respect to the circular injection pipe. The combustion gas flow orthogonal to the injection pipe flows along the cross section of the circular pipe with almost no turbulence, so the cleaning force depends only on the turbulence of the combustion gas flow due to the steam jet. Energy saving has not been taken into consideration because it is dealt with by increasing.

[0004]

In the conventional soot blower, when the heat transfer tube is cleaned by using self-steam in a small package boiler or a waste heat boiler, if the steam amount is small and the cleaning power is insufficient, There is a problem that energy saving is not taken into consideration because measures such as increasing the frequency of operation are taken. Further, since the injection hole for injecting the fluid is embedded from the outer surface of the circular pipe of the injection pipe, a groove for welding is applied to the outer surface of the circular pipe, but there is a problem that it becomes a three-dimensional processed surface and the processing is troublesome.

It is an object of the present invention to reduce the amount of steam by not only relying on the amount of steam but also to generate a cleaning force for the heat transfer tube in the injection pipe itself, thereby saving energy and reducing the time required for mounting the nozzle holes. To provide a soot blower that can achieve

[0006]

In order to achieve the above-mentioned object, a soot blower according to the present invention comprises a fluid supply mechanism and
A soot blower provided with at least one injection pipe connected to a supply mechanism and arranged to intersect with a heat transfer pipe, and at least one injection hole bored in a length direction of each injection pipe to eject a fluid The cleaning auxiliary mechanism for disturbing the combustion gas flow flowing in the intersecting direction is provided on the outer surface of each injection pipe.

The cleaning assisting mechanism may have a rectangular shape formed in the lengthwise direction of each injection pipe.

Further, the cleaning assist mechanism may be constituted by at least one fin attached in the lengthwise direction of each injection pipe.

[0009]

According to the present invention, since the cleaning assisting mechanism in which the outer surface of the injection pipe is formed into a square shape is provided, the combustion gas flow impinging on the square surface changes its direction largely and the combustion gas is disturbed. The flow prevents dust from adhering to the heat transfer tube. Since the injection pipe rotates during the operation of the sootblower, the turbulence of the combustion gas flow becomes large, and in addition to the steam injection, the cleaning power of the heat transfer pipe can be increased. Also in the finned injection pipe, the turbulence of the combustion gas flow is further increased by the fins, and the cleaning force is increased.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIG. FIG. 1 shows an installation drawing of a stationary rotary type sootblower equipped with a rectangular injection pipe. As shown in FIG. 1, a fluid supply mechanism, at least one injection pipe 22 that is connected to the supply mechanism and that is disposed so as to intersect with the heat transfer tube 10, and the respective injection pipes 22 are bored in the longitudinal direction. The soot blower is provided with at least one injection hole 13 for ejecting a fluid, and a cleaning assisting mechanism for disturbing the combustion gas flow flowing in the intersecting direction is provided on the outer surface of each injection pipe 22. The cleaning assisting mechanism has a rectangular shape shown in FIG. 2 formed in the length direction of each injection pipe 22 or each injection pipe 22.
At least one of the fins 15 and 16 shown in FIGS.

The supply mechanism is composed of the following parts, and the rotation of the gamutl 1 is transmitted to the super gear wheel 3 which meshes with the pinion 2, and the swivel tube 4 in which the super gear wheel 3 is fixed by a key is rotated. The sbell tube 4 is connected to the injection pipe 22 via the coupling 6 to rotate the injection pipe 22. The steam as the injection medium enters the injection pipe 22 from the steam pipe 8 via the gooseneck 7 and the swivel tube 4 and is ejected from the injection hole 13. Immediately after the connection of the gooseneck 7 to the steam pipe 8, a valve is built in, and its valve rod is mechanically operated by a cam attached to the spur gear wheel 3.

The injection pipe support 21 is attached to the boiler tube 10 at predetermined intervals with reference to the combustion gas temperature so that the injection pipe 22 can rotate smoothly. In this embodiment, since the injection pipe 22 is a square pipe, the rotary ring 14 shown in FIG. 3 is provided. Both ends of the rotating ring 14 are provided with a slope so that the injection pipe 22 can be easily inserted or withdrawn. As shown in FIG. 2, the cross section of the injection pipe 22 can easily attach the injection hole 13 to any position on the four surfaces. The injection pipe is not limited to the quadrangular pipe, and may be a polygonal polygonal pipe.

As another embodiment of the present invention, a finned injection pipe is shown in FIGS. FIG. 4 shows an embodiment in which fins 15 are attached in the lengthwise direction of a rectangular injection pipe. In this case, the fin 15 may be attached to the round injection pipe. In FIG. 5, a spiral fin 1 having a large lead in the round injection pipe 12 is shown.
An example in which 6 is attached is shown. Of course, in this case, it is also possible to attach it to a square injection pipe.

6 to 10 are prediction diagrams of the flow of combustion gas for the injection pipe 22 using the rectangular pipe of this embodiment. Although it is a prediction diagram of two kinds of combustion gas flows depending on the direction of the injection pipe 22, the combustion gas flow on the downstream side of the heat transfer pipe 10 is largely disturbed by the plane of the injection pipe 22 regardless of which position is stopped. . Due to this turbulent combustion gas flow, the boiler tube 1
In addition to preventing dust from adhering to No. 0, dust is peeled off from the boiler tube 10 even if it adheres.

According to the present invention, the cleaning efficiency is improved by using the rectangular injection pipe to generate the cleaning force for the heat transfer pipe in the injection pipe itself and disturbing the combustion gas flow.

Further, as another means for generating a cleaning force on the injection pipe itself, a spiral fin is attached in the length direction of the injection pipe to disturb the combustion gas flow to improve the cleaning force. This means may be adopted when emphasis is placed on generating a cleaning force on the injection pipe itself. The pipe to which the fins are attached may be either a square injection pipe or a round injection pipe. Even in the case of a finned injection pipe, the combustion gas flow hitting the fins is greatly disturbed and, as described above, it has the effect of preventing dust adhesion.

Further, since the combustion gas flow disturbed by the rectangular injection pipe can reduce the adhesion of dust to the heat transfer pipe even during standby, it is possible to reduce the frequency of steam injection and save energy.

The surface on which the injection holes are mounted is flat rather than circular. The welding groove shape is simplified, and the machining and welding work time can be shortened. Further, if necessary, the injection holes can be easily attached by changing the position at an angle of 90 ° for each pitch, and the cleaning efficiency can be improved.

[0019]

According to the present invention, since the injection pipe is provided with a rectangular shape or fins as a cleaning assisting mechanism, dust is attached to the heat transfer pipe even during standby due to the combustion gas flow disturbed by the injection pipe. Energy can be saved by reducing the frequency of steam injection. Further, since the surface on which the injection holes are mounted is flat, the shape of the weld groove is simplified, the machining and welding work time can be shortened, and the heat transfer tube cleaning efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a perspective view showing details of a B part in FIG.

FIG. 4 is a perspective view showing another embodiment of the injection pipe of the present invention.

FIG. 5 is a perspective view showing another embodiment of the injection pipe of the present invention.

FIG. 6 is a diagram for predicting combustion gas flow for an injection pipe of the present invention.

7 is a diagram for predicting a combustion gas flow in a cross section taken along the line C-C of FIG.

8 is a diagram for predicting a combustion gas flow in a cross section taken along the line D / D of FIG.

9 is a diagram for predicting another combustion gas flow in a cross section taken along the line C-C of FIG.

10 is a diagram for predicting another combustion gas flow in a cross section taken along the line D / D of FIG.

FIG. 11 is a diagram showing a conventional technique.

12 is a sectional view taken along line EE of FIG.

FIG. 13 is a diagram for predicting a combustion gas flow for a conventional injection pipe.

14 is a diagram for predicting a combustion gas flow in a cross section taken along line FF of FIG.

FIG. 15 is a diagram for predicting a combustion gas flow in a section taken along the line GG in FIG.

[Explanation of symbols]

 10 Heat Transfer Tube 12 Injection Pipe 13 Injection Hole 14 Rotating Ring 15 Fin 16 Fin

Claims (3)

[Claims] 1. A fluid supply mechanism, at least one injection pipe connected to the supply mechanism and arranged so as to intersect with a heat transfer tube, and the fluid is provided by drilling in the longitudinal direction of each injection pipe. A sootblower provided with at least one injection hole for ejecting the sootblower, characterized in that a cleaning assisting mechanism for disturbing a combustion gas flow flowing in a crossing direction is provided on an outer surface of each injection pipe. 2. The sootblower according to claim 1, wherein the cleaning assisting mechanism has a rectangular shape formed in a length direction of each of the injection pipes. 3. The sootblower according to claim 1 or 2, wherein the cleaning assisting mechanism is at least one fin attached in the longitudinal direction of each injection pipe.