JP2565807Y2 - Gas cooling chamber nozzle cleaning device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nozzle cleaning device for a gas cooling chamber, and particularly to an effect of dust adhering to an outer peripheral portion of a water jet nozzle provided in a gas cooling chamber used for municipal solid waste incineration facilities. The present invention relates to an apparatus for cleaning a nozzle portion of a gas cooling chamber for removing and cleaning.

[0002]

2. Description of the Related Art A municipal solid waste incineration facility, for example, a municipal solid waste incineration treatment process is shown in a block diagram of FIG. 4 in which the collected municipal solid waste is supplied to an incinerator by a dust supply device. It is thrown in and incinerated, and the incineration residue is removed from the incinerator and disposed of.
On the other hand, the high-temperature combustion exhaust gas is sent to a gas cooling chamber and cooled by spray water. After passing through an air preheater and a dust collecting device, it is sucked as a harmless gas by an induction blower and discharged to the atmosphere from a chimney.

A typical example of a gas cooling chamber of a municipal solid waste incineration plant will be described below with reference to FIG. It has a nozzle 56 for spraying water, a dust discharging device 53 including a dust scraping device 53a and a damper 53b for discharging at a lower portion, and an inner fire-resistant wall 51a at a position above the dust discharging device 53. And outer skin 51
b, and has an exhaust gas outlet 54 projecting obliquely upward from the lower side surface of the cooling chamber wall portion 51 composed of b and discharging exhaust gas cooled to the air preheater, the dust collecting device, and the like.

Further, as shown in FIG. 6 which is an explanatory view of the main part of the structure, the wall 51
And a nozzle fitting 55 having an air inlet 55a for blowing air for purging. A water spray nozzle 56 composed of a nozzle gun 56b for supplying spray water for cooling water and a nozzle tip 56a for spraying cooling water is loosely fitted to the nozzle fitting 55.

However, as shown in FIG. 7 showing the state of dust adhesion, the dust in the exhaust gas adheres to the opening of the refractory wall 51a around the water spray nozzle 56, and the water spray nozzle also takes time. The spray angle α of the spray water that grows as time passes and is sprayed from the water injection nozzle 56 is narrowed,
The spray water collides with the grown dust and becomes a drain, wets the refractory wall 51a and flows down.

[0006] The flow of the drain not only increases the adhesion of dust, but also erodes the refractory wall 51a, causing the refractory wall 51a to peel off or crack, etc., and corrosive gas, vapor, etc. entering from the portion. This causes corrosion of the anchor metal for refractory and the steel shell 51b, and also causes a problem that the exhaust gas cannot be cooled to a predetermined temperature due to deterioration of the water spray state.

As a technique capable of solving such a problem, for example, a technique disclosed in Japanese Utility Model Laid-Open No. 62-142626 is known. Hereinafter, this will be described with reference to FIG. 8 of a main part sectional view showing an exhaust gas cooling device. A water spray nozzle 56 for spraying water at a spray angle α into the gas cooling chamber is a nozzle welded to the steel shell 51b. Mounting bracket 5
5, the tip of which is attached to the refractory wall 5 of the gas cooling chamber 50.
It protrudes about 150 mm or more from the inner peripheral surface of 1a. Further, the nozzle 56 is provided with a ceramic protection tube 57 so that the tip of the nozzle tip 56a protrudes slightly.

Therefore, the water sprayed from the tip of the water spray nozzle 56 is prevented from hitting the ceramic protective tube 57 and draining, and the purge air supplied from the air inlet 55 a is blown out from the opening of the nozzle fitting 55. In addition, dust is prevented from adhering around the water spray nozzle 56 by avoiding contact with the exhaust gas.

[0009]

However, even when the purge air is blown around the outer periphery of the water spray nozzle, the purge air is diffused to the peripheral portion at the tip of the water spray nozzle, and there is no sufficient strength. The tip is not sufficiently protected, and starting from the tip, FIG.
Then, as shown in FIG. 9B of FIG. 9A as viewed in the direction of arrow B, dusts d ₁ and d ₂ start to adhere to the upper and lower portions of the outer periphery of the nozzle tip.

Further, even if the tip is covered with a protective tube, the tip of the nozzle tip of the water spray nozzle is rapidly covered by dust d ₃ deposited on the upper portion of the protective tube, and the water spray state is deteriorated. I will. If the adhesion of dust further progresses, it will be blocked up to the water spray hole of the nozzle tip, it will not be able to completely spray, the water will be large particles and flash flood, and it will fall without evaporating In addition to the problem that the sufficient cooling performance cannot be exhibited, there is also a problem that the consumption of the purge air is large and the solution is economically disadvantageous.

Therefore, an object of the present invention is to clean a nozzle portion of a gas cooling chamber, which makes it possible to effectively remove dust adhering to the tip of a water spray nozzle with a smaller amount of purge air than before. In providing the device.

[0012]

Means for Solving the Problems In order to solve the above problems, the main feature of the nozzle portion cleaning apparatus according to the present invention is characterized by spraying water onto high-temperature exhaust gas to cool the exhaust gas. Nozzle cleaning device for removing dust adhering to an outer peripheral portion of the water spray nozzle of a gas cooling chamber formed with a water spray nozzle having a front end portion protruding inward and penetrating a wall portion of the gas cooling chamber. In the present invention, an air injection nozzle having an air injection hole that is open toward the upper and lower outer peripheral portions and has an air injection hole for injecting purge air is provided at a position near the upper and lower outer peripheral portions at the distal end portion of the water spray nozzle.

[0013]

[Function] At the tip of the water spray nozzle protruding inside the gas cooling chamber, dust adheres and grows from the upper and lower outer peripheral parts,
Dust hardly adheres to the left and right outer peripheral portions. Therefore, according to the nozzle portion cleaning device of the present invention, the air injection nozzle having the air injection holes that open toward these upper and lower outer peripheral portions is provided in the vicinity of the upper and lower outer peripheral portions at the tip of the water spray nozzle. Therefore, the purge air is injected in a non-diffused state from the narrow air injection nozzle toward dust adhering to the upper and lower outer peripheral portions of the tip of the water spray nozzle.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the accumulation and growth of dust at the tip of a water spray nozzle is as follows. First, dust falls on the top of the nozzle tip at the tip of the water spray nozzle due to gravity and gradually becomes wet with water. It grows and accumulates in steep mountain shapes. Also, a phenomenon in which dust wet by the spray water adheres and grows gradually on the lower outer periphery of the water spray nozzle can be seen. The present invention is based on the idea that dust adhering and accumulating can be effectively removed from the tip of the water spray nozzle.

By the way, a comparison test of dust removal performance was performed between a case where compressed air is intensively sprayed to a dust adhering portion and a case where a conventional system in which purge air is blown from the entire circumference of a water spray nozzle. Table 1 shows the test results of the cold test and the hot test in comparison with each other. In the cold test, humidified dust having a moisture content of 20% was used. In Table 1, the case according to the conventional example is shown as the conventional method, and the case according to the present invention is described as the present method.

[0016]

[Table 1]

In an actual test using hot air, the adhesion state of dust at the tip of the water spray nozzle was smaller than that in a case where wet dust was dried by hot air and Ca in the dust reacted with water and was cold. In spite of the strong fixation, dust is reliably removed according to the present method, and sufficient removal performance is exhibited. In the conventional method, the dust removal performance during hot working is significantly reduced. Further, in the conventional method, the purge air escapes from the left and right outer peripheral portions while the dust remains on the upper and lower outer peripheral portions of the water spray nozzle, and the dust cannot be effectively removed. Therefore, the present inventors have developed a nozzle cleaning device having the following configuration for intensively injecting purge air to a dust attachment / growth site.

Hereinafter, an embodiment according to the present invention will be described with reference to FIG. 1A in a sectional view of a water injection nozzle mounting portion and FIG.
And FIG. 2 of the explanatory diagram of the purge air injection interval. The entire structure of the gas cooling chamber is the same as that described with reference to FIG. That is, reference numeral 10a shown in FIGS. 1a and 1b denotes a fireproof wall of the gas cooling chamber 10, and the fireproof wall 10a is provided with a through hole 10b for mounting a nozzle.
At 0b, a cylindrical nozzle fitting 11 having a flange portion 11a at a protruding end protruding outward and welded to an iron shell 10c covering the fireproof wall 10a is attached.

The nozzle fitting 11 has a water spray nozzle 12 comprising a nozzle gun 12b for supplying spray water and a nozzle tip 12a attached to the tip thereof.
However, the water spray nozzle 12 is loosely fitted with its tip side protruding inward, and the water spray nozzle 12 has a mounting flange 13 through which the nozzle gun 12b penetrates, which is fixed to the flange portion 11a of the nozzle mounting bracket 11, It is installed in the gas cooling chamber 10.

On the other hand, a nozzle portion cleaning device 1 to be described later is provided in the nozzle fitting 11. This nozzle unit cleaning device 1 includes two air injection nozzles 2 and 2 each having a water spray nozzle 1.
At the position sandwiching the second nozzle gun 12b from above and below, the air injection holes 2a are formed in the refractory inner surface 10 of the nozzle tip 12a.
The nozzle tip 1 is spaced apart from the end face on the d side by a distance of dimension a.
In a state where the mounting flange 13 penetrates through the mounting flange 13 with a distance b between the water spray nozzle 2a and the water spray nozzle 12, the outer periphery is welded and fixed to the flange. A compressed air supply pipe 3 provided with an electromagnetic on-off valve 3a for supplying compressed air as purge air from a compressed air supply source 4 communicates with the outwardly projecting end.

A steel pipe having a nominal diameter of 10 A is selected for the air injection nozzle 2 as a size that does not consume a large amount of air and can obtain an injection speed of 100 m / s or more.
By supplying compressed air at a pressure of 6 kgf / cm ² , purge air at a speed of 150 m / s or more was obtained.

The operation of the nozzle cleaning device 1 will be described below. The dust adheres and accumulates on the nozzle tip 12a, which is the tip of the water spray nozzle 12, and grows.
Since the purge air is intensively sprayed toward the dust from the gas injection holes 2a of the air injection nozzle 2 toward the dust at the lower outer peripheral portion, the purge air adheres to the upper and lower outer peripheral portions of the nozzle tip 12a.
Accumulated dust is effectively removed.

In this case, the purge air injection interval is, for example, as shown in FIG. 2, the purge air is supplied 1.5 times per one nozzle to a total of eight air injection nozzles 2 provided in the gas cooling chamber 10. After spraying for 2 seconds, stop for 60 seconds, repeat the purging of every 8 nozzles by the next air injection nozzle 2 and then stop for 1 hour, once per hour for each air injection nozzle 2 according to the pattern Dust can be effectively removed with a relatively small number of purges and air amount, and the gas cooling chamber 10 can be operated efficiently and stably for a long time without causing any abnormality in the water spray state. did it. The intermittent supply of the purge air is performed by opening and closing the electromagnetic on-off valve 3a using a timer (not shown).

On the other hand, the conventional method is 10 times less than the present method.
In addition to the consumption of compressed air of up to 20 times, the purge air escapes from the left and right outer peripheral parts other than the dust adhesion / deposition / growth area, so that once every 30 minutes to once every 10 minutes
I tried to make continuous injections five times,
Dust could only be partially removed and could hardly be removed, especially in the case of blackened dust containing more than 40% moisture.

The nozzle tip 1 of the water spray nozzle 12
The smaller the distance a between the end face of the refractory inner surface 10d on the side of the refractory inner surface 10d and the tip of the air injection nozzle 2 and the distance b between the nozzle tip 12a and the air injection nozzle 2, the more advantageous. Since the water spray nozzle 12 and the air spray nozzle 2 may interfere with each other and be damaged during installation, inspection, and removal work, the dimension a is actually 20 to 30 m.
m and the dimension b = 5 to 10 mm, no particular problem was observed in the dust removing effect.

Next, another embodiment according to the present invention will be described below with reference to FIG. 3 which is a sectional view of a water spray nozzle mounting portion. The difference between this embodiment and the above embodiment in the structure is as follows. As can be clearly understood from the figure, the tips of the two air injection nozzles 2 and 2 are respectively connected to the water spray nozzles 12.
Is bent at an angle β toward the nozzle tip 12a.

Therefore, from each of the air injection holes 2a, 2a of the air injection nozzles 2, 2, the nozzle tip 12a
Since the purge air is intensively injected toward the lower outer peripheral portion, this embodiment is the same as the above embodiment.

[0028]

As described above in detail, according to the nozzle cleaning apparatus for the gas cooling chamber according to the present invention, the dust is concentrated and concentrated on the upper and lower outer peripheral portions of the nozzle tip at the tip of the water spray nozzle. Since the purge air is injected from the air injection nozzle, it is possible to reliably remove adhered dust with a smaller amount of air than before, which is a great deal for maintaining the cooling capacity of the gas cooling chamber and reducing operating costs. effective.

[Brief description of the drawings]

FIG. 1a is a sectional view of a water injection nozzle mounting portion according to an embodiment of the present invention, and FIG. 1b is a view taken in the direction of arrow A in FIG. 1a.

FIG. 2 is an explanatory diagram of a compressed air injection interval according to the embodiment of the present invention.

FIG. 3 is a sectional view of a water jet nozzle mounting part according to another embodiment of the present invention.

FIG. 4 is a block diagram illustrating a flow of a municipal solid waste incineration process.

FIG. 5 is an explanatory diagram of a cross-sectional configuration of a gas cooling chamber.

FIG. 6 is an explanatory diagram of a main part configuration of FIG. 5;

FIG. 7 is an explanatory diagram of a dust adhesion state.

FIG. 8 is a sectional view of a main part showing a conventional gas cooling device.

9A is a view for explaining a dust adhesion start situation, and FIG. 9B is a view as seen from the arrow B in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Nozzle part cleaning device 2 ... Air injection nozzle, 2a ... Air injection hole 3 ... Compressed air supply pipe, 3a ... Electromagnetic on-off valve 10 ... Gas cooling chamber, 10a ... Fireproof wall, 10b ... Through-hole,
10c: steel shell, 10d: refractory inner surface 11: nozzle mounting bracket, 11a: flange portion 12, water spray nozzle, 12a: nozzle tip, 12b ...
Nozzle gun 13: Mounting flange

Continuation of the front page (72) Inventor Kenzo Ogura 1-3-18 Wakihama-cho, Chuo-ku, Kobe-shi, Hyogo Kobe Steel, Ltd. Kobe Head Office (56) References JP-A-2-25621 (JP, A) 62-142626 (JP, U)

Claims (1)

(57) [Scope of request for utility model registration] A water spray nozzle for spraying water onto a high-temperature exhaust gas to cool the exhaust gas is provided in a gas cooling chamber formed through a wall with a tip end of the water spray nozzle protruding inward. In a nozzle cleaning device for removing dust adhering to an outer peripheral portion of the water spray nozzle, purge air is opened toward these upper and lower outer peripheral portions at positions near the upper and lower outer peripheral portions of a tip portion of the water spray nozzle. A nozzle cleaning device for a gas cooling chamber, comprising an air injection nozzle having an air injection hole for injecting air.