JP2921064B2 - Exhaust duct dust removal device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention removes dust adhering and accumulating in an exhaust duct having a high dust content, such as an exhaust duct of a furnace for melting incineration ash. Related to the device.

[Conventional technology]

Recently, incinerated ash from various wastes such as municipal solid waste and sewage sludge is put into an arc-type melting furnace using base metal or a direct-current-type melting furnace using joule heat to reduce the volume and stabilize. Then, the melting process has been increased.
However, in these incinerator 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.

Conventionally, dust has been removed manually using a stick or the like.However, since high-temperature gas flows in the duct, work can only be performed when the furnace is shut down. The deposition is remarkable, and the surface of the dust is melted by the high-temperature gas, and the dust is deposited thereon to grow a molten solidified layer.

[Problems to be solved by the invention]

The present invention solves the above-mentioned conventional problems. Even during operation of a furnace that is a dust source, dust that adheres and accumulates in an exhaust duct can be automatically removed, and an exhaust duct that can prevent a blockage of the exhaust duct can be prevented. An object of the present invention is to provide a dust removing device for a duct.

[Means for solving the problem]

In the dust removal device for an exhaust duct according to the first aspect, a scraping plate whose lower side is opposed to the inner surface of the duct of the horizontal duct portion of the exhaust duct is supported so as to freely reciprocate in the horizontal direction through the end of the horizontal duct. A driving device mounted on a rod for reciprocatingly driving the rod, wherein the scraper plate has a hollow portion and a gas outlet communicating with the hollow portion, and a gas flow passage communicating the rod with the hollow portion. And a gas flow passage connected to a cooling gas supply source.

The dust removal device for an exhaust duct according to claim 2 is
The upper end of the elongated body extending vertically along the duct inner surface of the vertical duct part of the exhaust duct is attached to the arm fixed to the support shaft that passes through the center of the upper end of the vertical duct and is supported rotatably around the vertical axis. The arm has a hollow portion and a gas outlet communicating with the hollow portion, and the support shaft has a gas flow passage communicating with the hollow portion. And the gas flow passage is connected to a cooling gas supply source.

The dust removing device for an exhaust duct according to claim 3 is
A drive device that attaches a scraping plate whose lower side is opposed to the inner surface of the horizontal duct part of the exhaust duct to the rod that penetrates the end of the horizontal duct and is supported so as to be able to reciprocate horizontally in the horizontal direction, Along with the upper end of the elongated body extending vertically along the inner surface of the vertical duct portion of the exhaust duct, the upper end of the elongated body passes through the center of the upper end of the vertical duct and is supported rotatably around the vertical axis. The scraper has a hollow portion and a gas outlet communicating with the hollow portion, and the rod communicates with the hollow portion. The arm has a hollow portion and a gas outlet communicating with the hollow portion, and the support shaft is hollow in the arm. Gas flow to the section It has a road, characterized in that connected to the gas flow passage to the cooling gas supply source.

[Action]

In the exhaust duct dust removing device of the present invention,
A scraping plate, the lower side of which faces the inner surface of the duct of the horizontal duct, is reciprocally driven together with the rod by the driving device to scrape dust accumulated on the inner surface of the duct of the horizontal duct. The elongated body extending in the vertical direction along the inner surface of the duct of the vertical duct portion is swiveled around the vertical axis together with the arm by the driving device, and removes dust attached to the inner surface of the duct of the vertical duct.

The cooling gas supplied from the cooling gas supply source is
These parts are air-cooled by flowing through the rod and the scraping plate and / or the shaft and the arm.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

In the figure, 1 is an incineration ash melting furnace, 2 is a water-cooled exhaust duct connected to its exhaust port, and 3 is a gas cooling tower connected to the outlet of this exhaust duct 2. The exhaust duct 2 has a bent tubular shape and includes a vertical duct 4a, a horizontal duct 5a, a vertical duct 4b, and a horizontal duct 5b. In the vertical ducts 4a and 4b, a dust removing device 6a for blowing off and removing dust is provided.
6b is provided, and dust removing devices 7a and 7b for scraping and removing dust are provided in the horizontal ducts 5a and 5b.

The dust removing device 6a has a hollow arm 14 fixed to the lower end of a support shaft 13 rotatably supported around a vertical axis 12 by a bearing 11 at the center of the top plate 10 of the vertical duct 4a. An elongated heat-resistant steel chain 15 is suspended from the hooks 14A fixed to both ends, and the support shaft 13 is rotated at a low speed by a motor 16 via a drive chain 17. Chain 15 is the inner surface of the vertical duct 4a
It extends up and down a small distance from 18. A gas outlet 20 communicating with a hollow portion 19 of the arm is formed at both ends of the arm 14, and the hollow portion 19 is formed on the support shaft 13.
A gas flow passage 21 communicating with is provided. The upper end of the gas flow passage 21 opens into an air supply chamber 23 of a rotary joint 22 fixed to the top plate 10, and an air supply port 24 communicating with the air supply chamber 23 is provided with a cooling gas (for example, air). Or nitrogen gas) supply. Reference numeral 25 denotes a rotational position detecting piece having a base fixed to the support shaft 13, which is used for proximity switch operation (not shown). The dust removing device 6b has the same structure as the dust removing device 6a except for the length of the chain 15.

On the other hand, the dust removing device 7a is provided at the tip of a hollow rod 30 that extends through the end of the horizontal duct 5a and extends in the horizontal direction.
As shown, the lower side 31 is fixed to the opposing scraping plate 33 with a small clearance in the duct inner surface 32 of the horizontal duct 5a, and the rod 30 is supported on the frame 34 so as to be movable in the horizontal direction. Is provided with a driving device 35 for reciprocating driving. 36 is a guide block fitted to the end of the rod 30,
The side roller 37 and the lower roller 38 pivotally supported by this guide block travel along a guide rail (not shown),
A receiving roller pivotally supported at a position near the duct of the frame 34
39 supports rod 30. Both ends of a chain 43 wound around a driving sprocket 41 driven by a motor 40 and a driven sprocket 42 are guided by guide blocks.
The driving device 35 is connected to the driving device 36. As shown in FIG. 3, the scraping plate 33 has a hollow shape, and a gas outlet 46 communicating with the hollow portion 45 of the scraping plate is formed in the lower side 31 and one of the side plates 44. One end of a gas flow passage 47 formed in the rod 30 communicates with the hollow portion 45 of the scraping plate 33, and the other end of the gas flow passage 47 is provided for cooling through an expansion joint (not shown). Connected to a gas supply. The dust removing device 7b has the same configuration as that of the dust removing device 7a except that the reciprocating stroke of the scraping plate 33 and the length of the rod 30 and the chain 43 are different.

Next, an operation method and an operation of the dust removing device having the above configuration will be described.

First, during the operation of the incineration ash melting furnace 1, the rod 30 of the dust removing device 7 (general name of 7a and 7b; the same applies to other portions hereinafter) is retracted to the outside of the horizontal duct to remove the scraping plate. As shown by the solid line in FIG. 1, 33 is stopped at a standby position where it does not interfere with the chain 15 that is swiveling by the operation of the dust removing device 6. Then, the motor 16 of the dust removing device 6 is operated to rotate the arm 14 around the vertical axis 12 at a low speed of 10 revolutions per minute or less for a predetermined period of time (for example, 20 to 30 minutes), and turn along the duct inner surface 18. The dust attached to the inner surface is removed by the moving chain 15. After a predetermined time, the rotation position detecting piece 25 operates the proximity switch (not shown), and the arm 14 and the chain 15 are rotated by 90 degrees around the vertical axis 12 as compared with FIG. 1 (= the position shown in the third illustration). Stop. As a result, the chain 15 does not interfere with the reciprocating scraping plate 33 and stops at the side position of the moving passage of the scraping plate 33. Then, the driving device 35 is operated to
Is projected into the horizontal duct 5 and the scraping plate 33 is driven to the position indicated by the chain line 48 to scrape dust accumulated in the horizontal duct 5 and discharge it into the incineration ash melting furnace 1 and the gas cooling tower 3. I do. Then, after returning the scraping plate 33 to the first standby position, the operation of the dust removing device 6 is restarted, and the same process is repeated to remove dust in the exhaust duct 2 by dusting and scraping. Do it.

During the above process, the cooling gas supplied from the cooling gas supply source flows through the rod 30 of the dust removing device 7 and the inside of the scraping plate 33, and the inside of the support shaft 13 and the arm 14 of the dust removing device 6. And air-cooled so that these parts exposed to a high-temperature exhaust gas flow of about 1200 ° C. are not overheated.

The present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, the chain 15 is used as the elongated body for removing dust from the vertical duct 4, but instead, a single metal rod or a halfway folded part is used. A plurality of bendable metal bars or the like may be used, and the upper end of the metal bar may be hooked on the hook 14A or may be fixedly connected to the arm 14. Further, it is not necessary to provide a dust removing device in all of the vertical duct and the horizontal duct constituting the exhaust duct. For example, even if the dust removing device is omitted for a short vertical duct at the last stage of the exhaust duct, the dust removing device may be omitted. Good.

Although the exhaust duct of the incineration ash melting furnace has been described above, the present invention can also be applied to dust removal of the exhaust duct of a furnace for other uses. The present invention is also applicable to an exhaust duct in which the vertical and horizontal ducts are inclined at a small angle (for example, 15 degrees or less) with respect to the vertical and horizontal directions.

〔The invention's effect〕

As described above, according to the present invention, it is possible to automatically remove dust adhering and accumulating in the exhaust duct even during the operation of the furnace that is the dust source, and to shut off the exhaust duct and interrupt the furnace operation due to the accident. It contributes to preventing accidents.

Further, according to the present invention, since the cooling gas supplied from the cooling gas supply source flows through the rod and the inside of the scraping plate and / or the spindle and the arm to be cooled, it is possible to prevent overheating of these parts.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an exhaust duct dust removing apparatus showing one embodiment of the present invention, FIG. 2 is a detailed longitudinal sectional view of a portion A in FIG. 1, and FIG. 3 is a BB line in FIG. It is an expanded sectional view. 2 Exhaust duct, 4a, 4b Vertical duct, 5a, 5b Horizontal duct, 6a, 6b Dust remover, 7a, 7b Dust remover, 12 Vertical axis, 13 Shaft, 14 arm, 15 chain (slim body), 16 motor, 18
Duct inner surface, 19 ... hollow part, 20 ... gas outlet, 21 ...
Gas flow passage, 30 Rod, 31 Lower edge, 32 Duct inner surface, 33 Scraper, 35 Drive, 40 Motor, 45 Hollow, 46 Gas blow Exit, 47 ... gas flow passage.

Claims (3)

(57) [Claims] 1. A scraping plate whose lower side is opposed to the inner surface of a horizontal duct portion of an exhaust duct is attached to a rod which penetrates an end of the horizontal duct and is supported so as to be reciprocable in the horizontal direction. Comprising a driving device for driving, the scraping plate has a hollow portion and a gas outlet communicating with the hollow portion,
The rod has a gas flow passage communicating with the hollow portion,
A dust removing device for an exhaust duct, wherein the gas flow passage is connected to a cooling gas supply source. 2. A support shaft, which extends vertically along the inner surface of the vertical duct portion of the exhaust duct and extends through the center of the upper end of the vertical duct and is rotatably supported around a vertical axis. A driving device mounted on an arm fixed to the arm and rotatably driving the support shaft, wherein the arm has a hollow portion and a gas outlet communicating with the hollow portion, and the support shaft communicates with the hollow portion. A dust removal device for an exhaust duct, comprising: a gas flow passage that communicates with the cooling gas supply source. 3. A scraping plate whose lower side is opposed to the inner surface of the duct of the horizontal duct portion of the exhaust duct is mounted on a rod which penetrates through the end of the horizontal duct and is supported reciprocally in the horizontal direction. Equipped with a driving device for driving, and supports the upper end of the elongated body extending vertically along the inner surface of the vertical duct portion of the exhaust duct so that it can rotate around the vertical axis through the center of the upper end of the vertical duct. And a driving device attached to an arm fixed to the fixed support shaft and driving the support shaft to rotate. The scraping plate has a hollow portion and a gas outlet communicating with the hollow portion, and the rod is A gas flow passage communicating with the hollow portion, the gas flow passage being connected to a gas supply source for cooling, and the arm having a hollow portion and a gas outlet communicating with the hollow portion; Is connected to the hollow part of the arm. It has a gas flow path to the dust removing device of the exhaust duct, characterized in that connected to the gas flow passage to the cooling gas supply source.