JPH1019234A - Dust remover for duct - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dust remover having no rod driven in reciprocation in the longitudinal direction of a duct, nor incomplete operation due to the dust of the rod without carrying the dust outside and without requiring a large space for installing a device or projecting the rod outside an end part in the longitudinal direction of the duct. SOLUTION: A plurality of axes 11a to 11c which passe through the side wall of a duct (horizontal duct 2), are inserted into the duct and extend in the horizontal direction perpendicular to the longitudinal direction of the duct are arranged at prescribed pitches in the longitudinal direction of the duct. Each of the respective axes 11a to 11c is rotatably supported about each of the axes. The base parts of a plurality of scrapers 12a to 12c whose end parts are opposed to the inner surface 2d of the bottom part of the duct are respectively fixed to the respective axes 11a to 11c. A rotatively driving device for rotatively driving the respective axes is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for removing dust adhering and accumulating in a duct having a high dust content in a flowing gas, such as an exhaust duct of a furnace for melting incineration ash.

[0002]

2. Description of the Related Art Recently, incinerated ash from various kinds of waste such as municipal solid waste and sewage sludge has been put into an arc-type melting furnace or a direct current-type melting furnace in order to reduce the volume and stabilize. Melt processing has increased. However, in these incineration ash melting furnaces, there is a problem that the dust contained in the exhaust gas is large, and this dust adheres and accumulates in the exhaust duct, causing a duct blockage accident in a short time and interrupting the operation of the melting furnace. doing. In particular, the accumulation of dust is remarkable in the horizontal duct, and the surface of this dust is melted by the high-temperature gas, and the dust accumulates on it and a solidified layer grows. is there.

In order to solve the above-mentioned problems, the applicant has disclosed Japanese Patent Application Laid-Open Nos.
No. 257735 proposes a dust removing device. According to this apparatus, there is a great advantage that dust adhering and accumulating in the exhaust duct can be automatically removed even during the operation of the furnace which is a dust source.

[0004]

However, the dust scraping device of the horizontal duct portion of the device disclosed in the above-mentioned publication reciprocally drives the rod on which the scraping plate is mounted, so that dust adhering and accumulating on the rod is removed from the end of the duct. There has been a problem that a malfunction may occur due to biting into the sealing material at the rod penetrating portion of the wall, or the dust may go out of the sealing material together with the rod and scatter to the surroundings, thereby contaminating the duct periphery and deteriorating the working environment. . Further, a space for installing a rod driving device is required on the outer side in the longitudinal direction of the duct. In particular, in the device disclosed in Japanese Patent Application Laid-Open No. 4-103908, a large space is required due to a large rod protrusion, and other devices such as a gas cooling tower are required. And interference with the building skeleton in some cases.

[0005] In Japanese Unexamined Patent Publication No. 6-257735, since the rod is provided in the horizontal duct over the entire length of the duct, for example, when the melting furnace is tilted, a flange joint is formed so that an intermediate portion of the horizontal duct can be separated. It was impossible to adopt such a divided structure.

The present invention solves the above-mentioned conventional problems, and there is no rod reciprocally driven in the longitudinal direction of the duct.
Therefore, it is an object of the present invention to provide a dust removing device for a duct, which does not cause malfunction of the rod due to dust or take-out of the dust outside, and does not require a large space for installing equipment or protruding a rod outside a longitudinal end of the duct. And It is a second object of the present invention to provide a duct dust removing device that can be separated at an intermediate portion of the duct.

[0007]

According to the dust removing apparatus for a duct of the present invention, an axis which is inserted into the duct through a side wall of the duct and extends in a horizontal direction perpendicular to the longitudinal direction of the duct is provided with a predetermined axis in the longitudinal direction of the duct. A plurality of the scrapers are arranged at a pitch, each of the shafts is rotatably supported around the axis, and the bases of a plurality of scrapers whose front ends face the inner surface of the bottom wall of the duct are respectively attached to the respective shafts. It is characterized by comprising a rotation driving device that is fixed and drives the respective shafts to rotate.

According to a second aspect of the present invention, the rotary drive device is provided for each of the shafts.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. In the figure, reference numeral 1 denotes a vertical exhaust duct having a lower end connected to an exhaust port of an incineration ash melting furnace (not shown);
Reference numeral 5 denotes an exhaust horizontal duct having an inlet 3 connected to the upper end of the vertical duct 1, and reference numeral 5 denotes an inlet of a gas cooling tower connected to an outlet 4 of the horizontal duct 2. The horizontal duct 2 has a two-part structure having a flange connection portion 2c at an intermediate portion. When the incineration ash melting furnace (not shown) tilts at the time of tapping, a clamp tool (not shown) for fastening the flange connection portion 2c. ) Is opened and the ducts 2a and 2b are separated from each other.
Can move in a direction perpendicular to the plane of the paper of FIG. 1 (the direction of arrow X in FIG. 2), and can be tilted together with the vertical duct 1 integrally with the melting furnace.

Reference numeral 10 denotes a dust removing device, which includes three shafts 11a, 11b, which extend through the upper portion of the side wall of the horizontal duct 2 and are inserted into the duct and extend in the horizontal direction perpendicular to the longitudinal direction of the duct.
11c are arranged at a predetermined pitch P, and the bases of the scrapers 12a, 12b, and 12c whose front ends face the inner surface 2d of the bottom wall of the duct with a small clearance are fixed to the shafts. Each of the shafts 11 (general name of the shafts 11a to 11c; other members are also collectively referred to hereinafter) is a bearing 1 attached to frames 13a to 13c fixed to the outer shell of the horizontal duct 2.
By 4, it is rotatably supported around the axis.

A pinion 15 fixed to each shaft 11
A partial gear 18 formed on an upper portion of a lever 17 having an intermediate portion supported by a support shaft 16 on each frame 13 meshes with each other, and a lower end portion of the lever 17 is provided with air cylinders 19 a to 19 c attached to each frame 13. Rotation driving devices 20a, 20b, and 20c are provided that connect the piston rods and reciprocate (oscillate) the scraping body 12 by an angle of about 215 degrees by driving the air cylinder 19 to project and retract the piston rod.

[0012] As shown in FIG.
Is bent into a substantially triangular shape, and a scraping plate 22 is fixed to the end. The scraping plate 22 can be omitted unless a reduction in the scraping efficiency is a problem. The shaft 11 has a water-cooled double pipe structure in which a small-diameter steel pipe is inserted into a large-diameter steel pipe, and cooling water supplied from a cooling water inlet 23 passes through an inner flow passage 24 to form a steel pipe of the scraping body 12. After flowing through the inside 21 and cooling the scraping body 12 with water, the scraping body 12 is discharged from the cooling water outlet 27 of the rotary joint 26 through the outside flow passage 25. Reference numeral 28 denotes a rotary seal that seals a portion of the shaft 11 through the side wall of the duct. FIG. 3 illustrates a state in which the scraping body 12 has reached the lowermost position. Reference numeral 29 denotes a hole for inserting the scraping body 12 attached to the shaft 11 into a duct when assembling the apparatus.

In the dust removing apparatus 10 having the above structure, the scraping body 12 is normally held at the uppermost position extending in the longitudinal direction of the duct as shown by a solid line in FIG. As a result, the flow path resistance to the exhaust gas flow is kept low. To remove dust when dust accumulates on the bottom wall inner surface 2d of the duct and the dust accumulation layer 31 is formed,
First, the scraping body 12a is moved by the rotation
Rotate to the position indicated by. Thereby, the scraping body 12
The portion of the duct accumulation layer 31 below the portion a is scraped off, advances in the direction of arrow Q, and the dust accumulation layer 32 is formed below the scraping body 12b.

Then, the scraper 12a is returned to the uppermost position, the scraper 12b is rotated to the position indicated by the dashed line 35 in the same manner as described above by the rotation driving device 20b, and then is inverted to the uppermost position. And the dust accumulation layer 31 below the scraping body 12b is transferred to a position below the scraping body 12c.
Is driven to rotate in the same manner as described above, so that dust is discharged from the outlet 4 into the cooling device as indicated by the arrow R. As a result, the portion of the dust accumulated on the inner surface 2d of the bottom wall of the horizontal duct 2 within the rotation range of each scraping body 12 is removed. Steps may be repeated.

As described above, the driving of the scraping body 12 is performed by the rotation of the shaft 11, and the shaft 11 does not slide in the axial direction unlike the reciprocally driven rod of the conventional dust removing device. Dust adhered and deposited on the rotary seal 11 does not bite into the rotary seal 28 and cause malfunction, and is not taken out of the rotary seal and causes contamination. Further, the rotary drive device 20 is provided along the outer surface of the side wall of the duct, and no space for installing a device as a dust removing device is required outside the longitudinal end of the duct.

In this embodiment, the rotary drive 20a
To 20c are provided for each of the scrapers 12a to 12c, and are provided between the shafts 11a to 11c or each of the scrapers 12a to 1c.
Since there is no member for mechanically connecting the two furnaces 2c, when the melting furnace is tilted, the ducts 2a and 2b can be separated by releasing the fastening of the flange connection part 2c, and the duct 2a can be tilted without hindrance.

FIGS. 5 and 6 show another embodiment of the present invention, in which the same or corresponding parts as those in FIGS. 1 and 2 are denoted by the same reference numerals, and detailed description thereof will be omitted. . The horizontal duct 2 of this specific example is an integral type that does not have the flange connection portion 2c. In the dust removing device 50, the five shafts 11a to 11e are inserted into the center of the horizontal duct 2 through the upper and lower central portions of the side wall of the horizontal duct 2, and the scrapers 12a fixed to the shafts 11 are provided.
12e can rotate together with the shaft 11 around the axis.

The rotary drive unit 51 rotatably supports each shaft 11 on a frame 52 common to each shaft 11 by a bearing 14, and between two or one chain sprocket 53 attached to each adjacent shaft 11. The chain 54 is wound around the chain, and the chain sprocket 53 attached to the shaft 11e at the end of the chain row is driven by a single motor 55, whereby the shafts 11a to 11e are driven to rotate in conjunction with each other. I have.

In the dust removing apparatus 50 having the above-described structure, the scrapers 12 are normally kept in a horizontal state in the same direction as shown by a solid line in FIG. In order to remove dust, each shaft 11 is simultaneously driven in the same direction by the rotary drive device 51, and each scraping body 12 is moved in the same direction an appropriate number of times equal to or more than the number of shafts 11 (for example, 5 to 6 times). Rotate. As a result, the accumulated dust below each scraping body 12 is sequentially scraped and transferred in the direction of arrow Q, and discharged from the outlet 4 into the cooling tower.

In this embodiment, the rotation driving device 51 requires only one prime mover, so that the structure is simple. Further, since the shafts 11 are driven simultaneously, compared with the case where the shafts are sequentially driven as in the above-described embodiment. The control is simple and there is no possibility that interference between the scrapers 12 occurs.

The present invention is not limited to the above specific examples. For example, the scraping body may have a shape other than the above, such as a plate, and if the shaft passes through the center of the duct, A scraper may be fixed to both sides. However, in this case, it is necessary to determine the rotation timing and the stop position so that the scrapers of adjacent shafts do not interfere with each other. In addition, the prime mover and drive mechanism for rotating and driving the shaft may be other than those described above, and furthermore, the shaft and the scraping body may be cooled using gas, or the cooling may be omitted when the temperature in the duct is low. Is also good.

The present invention is also applicable to a case where the scraped dust is discharged and introduced into an apparatus upstream of a gas flow, a duct having an inclined shape inclined in a longitudinal direction, and an exhaust duct of an incineration ash melting furnace. It can also be applied to various ducts with high dust content.

[0023]

As described above, according to the present invention,
Since the driving of the scraping body for scraping the dust is performed by rotation of the shaft, there is no rod reciprocatingly driven in the longitudinal direction of the duct as in the conventional device, and therefore, malfunction of the rod due to dust or external dust. There is no take-out, and there is no need for a large space outside the longitudinal end of the duct for installing equipment and projecting the rod.

Further, according to the second aspect of the present invention, a rotary drive device is provided for each shaft so that the shafts are individually driven, so that the duct is provided at a position between the adjacent shaft and the rotary drive device. The duct can be separated, and the duct can have a divided structure in which the middle part can be separated.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an exhaust duct provided with a dust removing device according to one embodiment of the present invention.

FIG. 2 is a plan view taken on line AA of FIG. 1;

FIG. 3 is a sectional view taken along line BB of FIG. 2;

FIG. 4 is a sectional view taken along line CC of FIG. 3;

FIG. 5 is a view corresponding to FIG. 1 showing another specific example of the present invention.

FIG. 6 is a plan view taken along the line DD in FIG. 5;

[Explanation of symbols]

2 ... horizontal duct, 2a ... duct, 2b ... duct, 2d ...
Inner surface of bottom wall portion, 10: dust removing device, 11a: shaft, 11
b: shaft, 11c: shaft, 12a: scraper, 12b: scraper, 12c: scraper, 13a: frame, 13b: frame, 13c: frame, 14: bearing, 15: pinion, 17: lever, 18: Partial gear, 19a: Air cylinder, 19b: Air cylinder, 19c: Air cylinder,
20a: rotary drive, 20b: rotary drive, 20c
... Rotary drive device, 50 ... Dust removal device, 51 ... Rotary drive device, 52 ... Frame, 53 ... Chain sprocket, 54 ... Chain, 55 ... Motor.

Claims (2)

[Claims] 1. A plurality of axes extending through a side wall of a duct and inserted into the duct and extending in a horizontal direction perpendicular to the longitudinal direction of the duct at a predetermined pitch in the longitudinal direction of the duct, and each of the axes is set as an axis. A rotatable driving device that rotatably supports around the shaft, fixes the bases of the plurality of scrapers whose front ends face the inner surface of the bottom wall of the duct to the shafts, and drives the shafts to rotate. A dust removing device for a duct, comprising: 2. The dust removing device for a duct according to claim 1, wherein the rotary drive device is provided for each of the shafts.