JPH10169966A - Clinker generation preventing method for combustion furnace of product gas from waste melting furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent adhesion of clinker to a lower part of a combustion furnace with low-cost operation expenses by forming a cooling layer on a surface of an inner wall of the furnace by cold air diffused from a cold air nozzle directed in a circumferential tangential direction at a lower part of the furnace. SOLUTION: Four cold air nozzles 19 are disposed at a lower part of a combustion furnace 10 of generated gas from a waste melting furnace. The nozzles 19 are disposed on the same circumference of the inner wall of the furnace 10 in a tangential direction. Generate gas from the melting furnace is diffused in the furnace 20 by a burner 11, and burnt. At this time, combustible dust contained in the gas becomes molten or semi-molten state while burning, and flows down under the furnace 10. Meanwhile, cooling gas is raised while diffusing from the nozzles 19 along the wall to form a cooling gas layer on the wall in the furnace. Dust and the like of molten state is brought into contact with cooling gas immediately before colliding with the wall, cooled, and solidified, and dropped to a lower dust outlet 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for preventing the production of clinker in a combustion furnace for burning and processing a generated gas containing a large amount of dust generated from a waste melting furnace.

[0002]

2. Description of the Related Art In general, in a facility for burning waste and the like as described in Japanese Patent Application Laid-Open No. 5-340520, a gas produced in a melting furnace is burned together with a large amount of dust. Among these dusts, dust having a low melting point is contained, and partially melts in the burner flame and adheres to the lower portion of the combustion furnace and the dust discharge port, causing a problem such as blockage of this portion.
When the dust discharge port is closed, the operation of the furnace is temporarily stopped, and a dust discharge operation or the like is required, which lowers the operation rate of the furnace. On the other hand, JP-A-57-6772
No. 0 proposes a method in which a plurality of cooled rotating bodies are attached to a lower portion of a combustion furnace to cool molten or semi-molten dusts.

[0003]

However, in the technique described in the above publication, since the rotating body is directly installed in the high-temperature furnace, the rotating body is cooled down to a low temperature by using a large amount of cooling medium to protect the rotating body. It is necessary to repair the rotating part, and there is a problem that the operating cost is increased. Further, in the technology described in the above publication, since the lower body is also thermally shielded by the rotating body, it is necessary to reduce the gap between the rotating bodies, so that the blockage due to falling dust can be sufficiently eliminated. Did not. The present invention has been made in view of the above circumstances, and at relatively low operating costs, prevents clinker or the like from adhering to the lower part of a combustion furnace. The aim is to provide a method.

[0004]

According to the present invention, there is provided a semiconductor device comprising:
The method for preventing clinker generation in a combustion furnace of generated gas from a waste melting furnace according to the above is a method for preventing clinker generation in a combustion furnace for burning and processing a generated gas containing a large amount of dust generated from a waste melting furnace. A cooling air nozzle disposed in a lower part of the combustion furnace in a circumferential tangential direction, and a cooling air blown from the cooling air nozzle forms a cooling layer on a surface of an inner wall of the combustion furnace and a surface temperature of the inner wall. Has been lowered. Further, the method for preventing clinker generation of a combustion furnace of a gas generated from a waste melting furnace according to claim 2 is a method for preventing clinker generation in the combustion furnace, wherein the amount of cold air blown from the cold air nozzle is adjusted in the method of claim 1. Is maintained at a high temperature (for example, about 1000 ° C.) lower than the melting temperature of dusts. According to a third aspect of the present invention, there is provided a method for preventing clinker generation in a combustion furnace for generating gas from a waste melting furnace, wherein the cooled exhaust gas is supplied to the cold air nozzle in the method according to the first or second aspect. doing.

[0005] In the method for preventing clinker formation in a combustion furnace of a gas produced from a waste melting furnace according to claims 1 to 3,
At the bottom of the combustion furnace, a cool air nozzle that is directed in the circumferential tangential direction is arranged, and the cold air blown from the cold air nozzle forms a cooling layer on the surface of the inner wall of the combustion furnace, so that molten dust also solidifies However, it is possible to prevent the molten dust from adhering to this portion, and since the inner wall surface temperature is kept low, even if it adheres, it easily peels off, and as a result, clinker can be prevented from being generated. In particular, in the method for preventing clinker generation in a combustion furnace of a gas generated from a waste melting furnace according to claim 2, the temperature of the combustion furnace is set to a high temperature equal to or lower than the melting temperature of the dust, so that the dust fed into the furnace is reduced. Even if it is melted, it solidifies again, falls and is discharged from the lower dust outlet. In the method for preventing clinker generation in the combustion furnace of the generated gas from the waste melting furnace according to the third aspect, since the cooled exhaust gas is used for the cool air supplied to the cool air nozzle, the amount of oxygen is small. The temperature of the combustion furnace can be efficiently reduced.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 1 is an explanatory view of a method for preventing clinker generation in a combustion furnace of a gas generated from a waste melting furnace according to an embodiment of the present invention, and FIG. 2 is a view A in FIG.
It is -A sectional drawing.

As shown in FIG. 1, a combustion furnace 10 to which a method for preventing clinker generation in a combustion furnace of a gas generated from a waste melting furnace according to an embodiment of the present invention is applied. A furnace for burning generated combustible gas, comprising a burner 11 to which a combustion gas is supplied in an intermediate portion, a lower portion having a reduced diameter like an inverted truncated cone, and a dust outlet 12 provided in a bottom portion. I have. Then, the high-temperature combustion exhaust gas discharged from the exhaust port 13 in the upper part of the combustion furnace 10 is supplied to a boiler 14 to recover heat, and further passes through an exhaust gas temperature controller 15 to be cooled to about 150 ° C. The exhaust gas cooled to 150 ° C. is collected by a filter type dust collector 16 to collect dust, passes through a suction fan 17, and further removes NOx and the like contained by a device (not shown).
From the air.

In the lower part of the combustion furnace 10, four cold air nozzles 19 are evenly arranged. This cold air nozzle 19
As shown in FIG. 2, are arranged in the tangential direction of the same circumference of the inner wall surface of the combustion furnace 10, and a cooling layer is formed on the wall surface of the combustion furnace 10 by the blown cool air. . As the cool air supplied to the cool air nozzle 19, in this embodiment, exhaust gas having a temperature of about 150 ° C. is used, and the cool air on the exhaust side of the suction fan 17 is supplied to the four cool air nozzles via the regulating valve 20. Leading to 19.

A thermometer 21 for measuring the temperature of gas in the vicinity of the inner wall of the furnace is arranged at an intermediate portion of the combustion furnace 10, and is adjusted via a control device 22 so that the temperature of the gas to be measured is about 1000 ° C. The amount of the cool air sent to the cool air nozzle 19 is adjusted by adjusting the valve 20. This is because if the temperature in the combustion furnace 10 is too low, the combustion state of the supplied combustible gas and char becomes unstable, and the thermal efficiency of the boiler 14 in the next step decreases. If the temperature is too high, it is contained in the combustible gas. This is because the combustible dust falls in a molten state and clinker is easily generated. Therefore, the melting temperature of combustible dust is about 1100
℃, the temperature of the combustion furnace 10 is 900-105
It is appropriate to keep the temperature at 0 ° C. (more preferably, about 1000 ° C.). The combustion furnace 10 shown in FIG. 1 is provided with a secondary air supply port (not shown) and a pilot burner.

Therefore, the generated gas generated from the melting furnace is:
The gas is blown into the combustion furnace 10 by the burner 11 and burned. At this time, the combustible dust contained in the generated gas is in a molten or semi-molten state while burning, and the combustion furnace 1
Flow down below zero. On the other hand, the cooling gas is
As a result, a cooling gas layer is formed on the inner wall of the furnace. Dust in a molten state comes into contact with the cooling gas layer immediately before colliding with the wall surface, rapidly cools and solidifies, and the dust exhaust port 1 in the lower portion.
Fall to 2. As described above, the cooling gas amount is controlled by the adjusting valve 20 so that the lower wall surface temperature is equal to or lower than the dust melting temperature (about 1000 ° C.).

In the above-described embodiment, low-temperature combustion exhaust gas is used as the cooling gas. However, air can be used, and in some cases, water cooling can be performed by installing a water spray nozzle. In addition, in FIG.
Reference numeral 4 denotes a refractory.

[0012]

As is apparent from the above description, the method for preventing clinker generation in a combustion furnace of a gas produced from a waste melting furnace according to the first to third aspects can prevent the clogging of dust in the combustion furnace. There is no downtime, and the operation rate of the furnace is improved. In addition, the cooling layer temperature formed by the cool air blown out from the cool air nozzle may be maintained at a temperature equal to or lower than the melting temperature of the dust, and is not cooling the entire lower part of the combustion furnace, but cooling only the furnace wall surface. Therefore, the amount of cooling medium used can be reduced, the operating cost can be reduced, and the overall thermal efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a method for preventing clinker generation in a combustion furnace of a gas generated from a waste melting furnace according to an embodiment of the present invention.

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

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Combustion furnace 11 Burner 12 Dust discharge port 13 Exhaust port 14 Boiler 15 Exhaust gas temperature controller 16 Filtration type dust collector 17 Suction fan 18 Chimney 19 Cold air nozzle 20 Adjustment valve 21 Thermometer 22 Control device 23 Iron shell 24 Refractory

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Shunji Yamauchi 46-59 Nakahara, Toba-ku, Kitakyushu-shi, Fukuoka Prefecture Nippon Steel Plant Design Co., Ltd.

Claims (3)

[Claims] 1. A method for preventing clinker generation in a combustion furnace for burning a generated gas containing a large amount of dust generated from a waste melting furnace, comprising: A method for preventing clinker generation in a combustion furnace of a gas generated from a waste melting furnace, wherein a nozzle is disposed and a cooling layer is formed on a surface of an inner wall of the combustion furnace by cold air blown from the cold air nozzle. . 2. The gas generated from a waste melting furnace according to claim 1, wherein the temperature of the combustion furnace is maintained at a high temperature equal to or lower than the melting temperature of dust by adjusting the amount of the cool air blown out from the cool air nozzle. A method for preventing clinker formation in a combustion furnace. 3. The method for preventing clinker generation in a combustion furnace of a gas generated from a waste melting furnace according to claim 1, wherein the cooled exhaust gas is used as the cool air supplied to the cool air nozzle.