JPH11325445A - Ash melting furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively and securely melt an ash fraction with excellent corrosion resistant, heat resistant, and simplified structure, and realize turning-up and turning-down of a furnace in a short time. SOLUTION: An ash melting furnace body 27 is formed with a heat resistant and corrosion resistant ceramics tapered tube 27a, so that an ash fraction is made slag without a high temperature reaction with a CaO component of the ash fraction, and a furnace inner wall 27d is effectively prevented from being damaged. Thus, spalling resistance is improved, and starting-up and stopping of the furnace are realized in a short time. Further, molten slag 21 is effectively discharged, and complete decomposition of harmful substances in a secondary combustion chamber 28 and combustion heat in the same chamber 28 are effectively utilized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ash melting furnace attached to a municipal solid waste incinerator or an industrial waste incinerator for melting ash generated in a furnace facility such as an incinerator or a gasification furnace. is there.

[0002]

2. Description of the Related Art In recent years, with the decrease in landfill sites for garbage,
There is a demand for reduction of incineration ash, and the development of incineration ash melting means capable of significantly reducing the amount is in progress. However, the melting process of incinerated ash requires reheating because it is melted after incineration of garbage, consuming a lot of energy,
There was a disadvantage that the cost was high. For this reason, ash melting furnaces have been developed based on the idea of recovering combustion energy during incineration and using the recovered energy as ash melting energy after incineration.

As one example, for example, Japanese Patent Publication No. 1-52
There is a waste incineration system disclosed in Japanese Patent No. 654.
FIG. 13 is a principle diagram showing a waste incineration system disclosed in Japanese Patent Publication No. 1-26544. In FIG.
120 is a fluidized bed incinerator, 121 is waste, 122 is residual ash discharged from the fluidized bed incinerator 120, 123 is fine ash called fly ash (not shown) and flammable pyrolysis gas (not shown) will be described later. The flue sent to the ash melting furnace body 125, 12
4 is a pulverizer for finely pulverizing the residual ash 122. Also,
Reference numeral 125 denotes an ash melting furnace main body that heats and melts the ash (hereinafter, simply referred to as “ash”) such as the crushed residual ash 122 and the fly ash described above, and the furnace wall has a heat-resistant brick or an irregular castable refractory. The inner wall of the furnace is formed of a cementing structure or the outer periphery of the furnace is covered with a thick heat insulating material (not shown). 126 is a molten slag, 12
Reference numeral 7 denotes a slag reservoir, and 128 denotes a heat exchanger for preheating the combustion air by the heat of the exhaust gas.

Next, the operation will be described. Waste 121
When the waste 121 is supplied to the fluidized bed incinerator 120 that supplies air that is slightly insufficient with respect to the supply amount, the combustion state becomes incomplete, and the residual ash 122, fly ash (not shown), and unburned flammable Generates pyrolysis gas. The fly ash (not shown) and the flammable pyrolysis gas are led to the ash melting furnace main body 125 by the flue 123. In addition, the residual ash 122 is crushed by a pulverizer 124.
And then supplied to the ash melting furnace body 125 in the same manner as fly ash.

[0005] The ash melting furnace body 125 is supplied with combustion air so as to swirl along the inner wall by a melting burner (not shown) or the like so as to melt the ash. Is also mixed. As a result, the ash melting furnace main body 125 obtains a combustion state, so that the ash melting furnace body 125 is maintained at a high temperature of about 1200 ° C. or more, fine ash is melted in a swirling flow and changes into molten slag 126, and the slightly coarse ash is When it comes into contact with the wall surface, it is melted and changes to a molten slag 126. The molten slag 126 thus generated is dropped and collected in the slag reservoir 127. The high-temperature exhaust gas preheats the combustion air in the heat exchanger 128 and is discharged into the atmosphere.

[0006]

Since the conventional ash melting furnace is configured as described above, the Al and Si components contained in the furnace wall made of a heat-resistant brick or an amorphous castable refractory are converted into incinerated ash. There is a problem in that a low melting point substance is generated by reacting with the CaO component contained therein, and the furnace wall is eroded when the slag flows through the furnace wall.

Further, the slag trapped on the furnace wall at a low temperature in the early stage of combustion is transmitted through the furnace wall due to the swirling flow.
Despite the melting, the residence time on the furnace wall becomes longer, and there is a problem that the furnace wall may be damaged as a whole.

Furthermore, since a refractory brick or an amorphous castable refractory is used as a heat insulating member with respect to the outside air, the heat capacity is large and the heat spalling property is low, so that the heating rate of the furnace is 200 ° C. or less per hour. Was restricted. Therefore,
There were problems that it took time to start up and shut down the furnace, and required a great deal of energy to raise the furnace to the ash melting temperature.

Further, the furnace wall is made of refractory bricks or irregular castable refractories, and the inner wall has a cementing structure. If the inner wall is damaged or worn, even if it is partially damaged, etc. All the internal refractory materials and the like had to be replaced, which required a skilled technique and a great deal of time, and had problems such as being unable to be easily repaired.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has excellent corrosion resistance and heat resistance, can efficiently and surely melt ash by a simple structure, and can start up and shut down a furnace. To obtain an ash melting furnace that can perform the ash melting in a short time.

Another object of the present invention is to provide an ash melting furnace in which the inner wall of the furnace is hardly damaged, and which can be easily and quickly repaired even if damaged.

[0012]

In the ash melting furnace according to the present invention, the main body of the ash melting furnace provided on the inner surface of the heat insulating container is made mainly of a single heat-resistant and corrosion-resistant silicon carbide (SiC). It is formed by a ceramic tube which is a sintered body.

In the ash melting furnace according to the present invention, the main body of the ash melting furnace having a heat insulating space formed between the inner surface of the heat insulating container and a single silicon carbide (SiC) having heat resistance and corrosion resistance is used as a main component. It is formed by a ceramic tube which is a sintered body.

The ash melting furnace according to the present invention is formed by connecting a plurality of ceramic tubes, which are sintered bodies mainly composed of silicon carbide (SiC) having heat resistance and corrosion resistance, to the ash melting furnace main body. is there.

In the ash melting furnace according to the present invention, the entire shape of the ash melting furnace main body is formed into a truncated cone, and an ash supply section is provided on an inner wall portion where the inner diameter of the ash melting furnace main body is minimized. A slag discharge section is provided at the bottom of the inner wall where the inner diameter of the melting furnace main body is maximum.

The ash melting furnace according to the present invention has an ash melting furnace main body formed in a cylindrical shape as a whole, an ash supply section provided on an inner wall at one longitudinal end of the ash melting furnace main body, and an ash melting furnace. A slag discharge portion is provided at the bottom of the inner wall at the other end in the longitudinal direction of the main body, and the ash melting furnace main body is tilted such that the slag discharge portion is located at a lower position.

The ash melting furnace according to the present invention has a sintering furnace mainly composed of a plurality of silicon carbides (SiC) having different inner diameters so that the inner diameter of the ash melting furnace body increases from one end to the other end in the longitudinal direction. An ash supply unit for connecting ash to the inner wall of a ceramic cylindrical tube having a minimum inner diameter by connecting a ceramic cylindrical tube as a body, and sintering mainly composed of silicon carbide (SiC) having a maximum inner diameter A slag discharge portion is provided at the bottom of the inner wall of a ceramic cylindrical tube as a body, and the ash melting furnace main body is installed so that the central axis is horizontal.

The ash melting furnace according to the present invention comprises a ceramic tube which is a sintered body mainly containing silicon carbide (SiC) and another ceramic tube which is a sintered body mainly containing silicon carbide (SiC). One of an engagement projection and an engagement recess engageable with each other is provided at an end to be connected.

In the ash melting furnace according to the present invention, the engaging convex portion and the engaging concave portion are each formed in a tapered shape to form an engaging tapered portion.

The ash melting furnace according to the present invention is provided with an urging means for urging at least one of both longitudinal ends of the ash melting furnace main body inward.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a principle diagram schematically showing a system using an ash melting furnace according to Embodiment 1 of the present invention.
In FIG. 1, reference numeral 1 denotes a fluidized bed gasifier (furnace facility), 2 denotes a refuse 3 crushed and stored to about 10 to 30 mm and is supplied to the fluidized bed gasifier 1 via a refuse quantitative supply device 4. The waste supply hopper 5 preheats the outside air and burns air 5a.
, An auxiliary burner 6 that assists with fuel 7, an air diffuser 8 that supplies combustion air 5 a to the fluidized bed gasifier 1, and fluidizes the fluidized sand 9, and 10 is heated. Pyrolysis gas generated from refuse 3, 11 is pyrolysis gas 1
It is fly ash (ash) contained in 0.

Reference numeral 12 denotes a cyclone for separating the pyrolysis gas 10 and fly ash 11, 13 denotes an ash supply device for supplying the fly ash 11 separated by the cyclone 12 to an ash melting furnace 20, which will be described later, and 16 denotes an ash supply device 13. The pre-combustion chamber 17a mixes the fly ash 11 and the combustion air 5a supplied from the furnace and burns the mixture by the auxiliary combustion of the melting burner 17, and 17a is a fuel supplied to the melting burner 17. Reference numeral 20 denotes an ash melting furnace which heats and melts the ash passing through the pre-combustion chamber 16 and discharges it as a molten slag 21 and discharges an exhaust gas 22; 23, an exhaust gas treatment device; 27, an ash melting furnace main body to be described later; This is a secondary combustion chamber (insulated space).

Next, the ash melting furnace 20 will be described in more detail with reference to FIG. Here, FIG. 2 is a vertical sectional view showing the ash melting furnace. In FIG.
, A heat-insulating container in which another cylinder is suspended from a bottomed cylinder installed horizontally, 25 is a gas outlet (exhaust portion) as an opening of the heat-insulating container 24, and 26 is provided on the entire inner surface of the heat-insulating container 24. Heat insulation.

Reference numeral 27 denotes an ash melting furnace body for heating and melting ash such as fly ash 11. The ash melting furnace main body 27 has a body portion formed of a ceramic tapered tube (single silicon carbide (SiC)) which is a sintered body mainly composed of a single silicon carbide (SiC) having corrosion resistance and heat resistance. The entire shape is formed into a truncated cone by being formed by a ceramic tube (a ceramic tube) 27a, which is a sintered body having a main component, and fitting and closing both ends thereof by end plates 27b and 27c of the same material. The end plates 27b and 27c of the ash melting furnace main body 27 are fixed to the heat insulating material 26 so that the central axis thereof is horizontal. Examples of the ceramic material which is a sintered body containing silicon carbide (SiC) as a main component include, for example, a SiC content of 95% or more and a firing temperature of 1300 ° C.
Those made from the above SiC can be used.

Reference numeral 28 denotes a secondary combustion chamber formed between the ash melting furnace main body 27 and the heat insulating material 26. The secondary combustion chamber 28 converts the pyrolysis gas 10 and the combustion air 5a supplied from a pyrolysis gas supply nozzle 33 described later. In addition to burning, the exhaust gas 22 is also completely burned, and the ash melting furnace main body 27 is heated from the surroundings by the combustion heat.

Reference numeral 29 denotes a fly ash supply nozzle (ash supply unit) for supplying the fly ash 11 and the combustion air 5a together with the flame from the pre-combustion chamber 16 to the ash melting furnace main body 27 from the tangential direction of its inner diameter. It is provided on a furnace inner wall (inner wall portion) 27d where the inner diameter of the furnace main body 27 is minimized. 30 is the ash melting furnace main body 2
A slag discharge port (slag discharge portion) 31 is provided at the bottom of the furnace inner wall 27d where the inner diameter of the ash melting furnace main body 27 is maximum to discharge the molten slag 21 in order to discharge the molten slag 21. , 32 are slag discharge pipes connected to the slag discharge port 31, 33 is pyrolysis gas 10 and combustion air 5
This is a pyrolysis gas supply nozzle that supplies a to the secondary combustion chamber 28.

Next, the operation will be described. First, garbage 3
The waste is supplied from the refuse supply hopper 2 to the fluidized bed gasifier 1 via the refuse fixed amount supply device 4. Then, the air for combustion 5a is supplied from the air diffuser 8 and the fluidized sand 9 is fluidized, so that the inputted refuse 3 is miniaturized and mixed.
Further, the fluidized sand 9 is heated to 450 to 6 by the combustion burner 6.
When heated to 00 ° C., pyrolysis gas 10 is generated from the refuse 3. At this time, in order to prevent complete combustion of the pyrolysis gas 10 in the fluidized-bed gasification furnace 1, the air ratio in the furnace is set to 0.
It is about 3 to 0.4. The components of the pyrolysis gas 10 vary depending on the quality of the refuse 3, for example, CO, CH
_4, are made of, such as H _2.

Since the pyrolysis gas 10 discharged from the fluidized-bed gasifier 1 contains fly ash 11, the cyclone 1
2 and separated into pyrolysis gas 10 and fly ash 11. The separated pyrolysis gas 10 is mixed with the combustion air 5a and is supplied to the ash melting furnace 20 by the pyrolysis gas supply nozzle 33.
Is introduced into the secondary combustion chamber 28. The separated fly ash 11 is conveyed from the cyclone 12 to an ash crusher (not shown) and crushed to a particle size of 1 mm or less. Crushed fly ash 1
1 is mixed with the combustion air 5 a preheated by the air preheater 5, supplied to the pre-combustion chamber 16, and pre-combusted by the auxiliary combustion of the melting burner 17.

The exhaust gas containing the ash that has passed through the pre-combustion chamber 16 is injected from the tangential direction of the inner diameter of the furnace inner wall 27d by the auxiliary combustion of the melting burner 17, so that it is swirled in the ash melting furnace main body 27 to be mixed and stirred. The ash melts. For example,
When a heat-resistant ceramic material made of SiC having an SiC content of 95% or more and a sintering temperature of 1300 ° C. or more is used for the ash melting furnace main body 27, the fly ash 11 having a relatively large particle diameter can be formed in the furnace inner wall at an early stage. The molten slag adheres to 27d and becomes molten slag 21. At this time, the molten slag 21 is
Since the bottom is inclined toward the slag discharge port 31, the bottom flows toward the slag discharge port 31 by the action of gravity and is discharged from the slag discharge pipe 32 to the outside. At this time, since the furnace inner wall 27d is made of ceramics SiC having corrosion resistance and heat resistance, the ash C
Slag is formed without reacting with the aO component at a high temperature, and damage to the furnace inner wall 27d is effectively prevented.

On the other hand, the fly ash 11 having a relatively small particle size is heated while turning around the center of the ash melting furnace main body 27 in a swirling flow to become a molten slag 21 and the furnace inner wall 2.
Trapped at 7d. The trapped molten slag 21 also flows through the furnace inner wall 27 d toward the slag discharge port 31 and is discharged to the outside from the slag discharge pipe 32. In addition,
The viscous molten slag 21 discharged from the slag discharge port 31 is water-cooled and solidified by a water-cooling and solidifying means (not shown) and collected.

The gas outlet 30 of the ash melting furnace main body 27
Is mixed with the pyrolysis gas 10 and the combustion air 5a supplied from the pyrolysis gas supply nozzle 33 in the secondary combustion chamber 28, for example, at 900 ° C.
Since the secondary combustion is performed at the above high temperature, harmful substances such as dioxin are completely decomposed. And the secondary combustion chamber 28
The combustion heat generated in the furnace is converted into the furnace inner wall 27d of the ash melting furnace main body 27.
Is heated and effectively used for melting ash. Therefore, the heat insulating performance of the ash melting furnace main body 27 is remarkably improved as compared with the conventional case where the heat insulating material is directly provided on the outer peripheral surface of the ash melting furnace. That is, it is possible to reduce the heat energy consumption at the time of raising the temperature of the ash melting furnace 20, shorten the time required for the temperature rise, and suppress the loss of the heat energy even at the time of the steady operation to efficiently melt the ash. The exhaust gas 22 after the secondary combustion is introduced into the air preheater 5 through the gas discharge port 25, and after preheating the air, is introduced into the exhaust gas treatment device 23 and discharged to the outside air.

In order to verify the high-temperature reaction on the furnace inner wall 27d, a melting test was performed to determine how much the molten fly ash 11 reacts with the material of the furnace inner wall 27d.
That is, a reaction test was performed by placing incinerated ash on a heat-resistant ceramic Al ₂ O ₃ and SiC substrate having an outer diameter of 50 mm and a thickness of 5 mm. Heating is performed in an electric furnace and the temperature condition is 14
The temperature was raised to 00 ° C. for 7 hours, maintained at 1400 ° C. for 5 hours, and then allowed to cool naturally. As a result, 91 μm for Al ₂ O ₃
m, melting damage was confirmed, but no melting damage was detected with SiC. For this reason, ceramics SiC excellent in corrosion resistance and heat resistance and having a firing temperature of 1300 ° C. or more
Is used for the material of the ash melting furnace main body 27,
Does not react with CaO contained in the furnace inner wall 27d
It has been verified that the melting damage of the steel can be effectively prevented.

As described above, according to the first embodiment, the ash melting furnace main body 27 is a ceramic taper which is a sintered body mainly composed of single silicon carbide (SiC) having corrosion resistance and heat resistance. Since it is formed by the tube 27a,
Slag is formed without reacting with the CaO component of the ash at a high temperature, and the effect of effectively preventing damage to the furnace inner wall 27d is obtained. In particular, this ceramic SiC, unlike refractory bricks and amorphous castable refractories, has a small number of pores and a high density, so the ash melted at high temperature hardly erodes into the castable as a clinker, and the furnace inner wall 2
The effect that can effectively contribute to the prevention of erosion of 7d is obtained. In addition, since the ceramic SiC has high spalling resistance, an effect that the furnace can be started up and shut down in a short time can be obtained.

Further, since the ash melting furnace main body 27 is formed of a single ceramic tapered tube 27a which is a sintered body mainly containing silicon carbide (SiC), it is larger than a cylindrically formed one. As well as securing a heat transfer area,
There is no need to install the ash melting furnace main body 27 or the heat insulating container 24 at an angle, and the molten slag 21 can be efficiently flowed and discharged with a simple structure.

Further, harmful substances such as dioxin can be completely decomposed by the secondary combustion in the secondary combustion chamber 28, and the heat of combustion generated in the secondary combustion chamber 28 is melted in the ash melting furnace main body 27. Can be used effectively.
Therefore, the heat insulation performance of the ash melting furnace main body 27 is significantly improved as compared with the conventional case where the heat insulating material is directly provided on the outer peripheral surface of the ash melting furnace. In addition to reducing consumption, the time required for temperature rise can be reduced, and the effect of suppressing the loss of heat energy and efficiently melting ash can be obtained even during steady operation.

In the first embodiment, the present invention has been described as being applied to the fluidized-bed gasifier 1, but the present invention is not limited to this, and is applicable to furnace facilities such as incinerators that generate ash. Also, the same effect as in the first embodiment can be expected.
Further, the end plates 27b and 27c of the ash melting furnace main body 27 have been described as being fixed and installed on the heat insulating material 26. However, the present invention is not limited to this. In this case, the same effect as in the first embodiment can be expected. Further, by providing a combustion device such as a burner in the secondary combustion chamber 28, the ash melting performance of the ash melting furnace main body 27 can be further improved. Furthermore, the ash melting furnace main body 27 has been described as being formed into a truncated conical shape by a single ceramic tapered tube 27a which is a sintered body mainly containing silicon carbide (SiC). A slag discharge port 3 formed of a ceramic cylindrical tube which is a sintered body containing silicon carbide (SiC) as a main component.
The ash melting furnace main body 27 can also be formed so as to be inclined so that 1 is located below the inclination. In this case, the same effect can be expected.

Embodiment 2 FIG. 3 is a sectional view showing an ash melting furnace according to a second embodiment of the present invention, and FIG.
FIG. 4 is a cross-sectional view. In the following description, the same or corresponding members as those already described are denoted by the same reference numerals, and description thereof will be omitted or simplified. 3 and 4, reference numeral 27e denotes a ceramic cylindrical tube which is a sintered body mainly composed of silicon carbide (SiC) made of ceramic SiC having the same corrosion resistance and heat resistance as the material used in the first embodiment. (Ceramic tube). Also, reference numeral 35 denotes an engaging protrusion protruding from one end in the longitudinal direction of a ceramic cylindrical tube 27e which is a sintered body mainly containing silicon carbide (SiC). This is an engagement concave portion provided at the other end. The engagement projections 35 and the engagement recesses 36 are formed with predetermined fitting dimensions in consideration of thermal expansion and the like, and when the ash melting furnace main body 27 is repaired or the like, each silicon carbide (SiC) is formed. It is formed so that a ceramic cylindrical tube 27e, which is a sintered body having a main component, can be independently rotated around a central axis. As described above, the entire shape of the ash melting furnace main body 27 is formed by connecting a plurality of ceramic cylindrical tubes 27 e, which are sintered bodies containing silicon carbide (SiC) as a main component, with the engaging convex portions 35 and the engaging concave portions 36. The slag outlet 3 is formed in a cylindrical shape.
The heat insulating container 24 is inclined so that 1 is located below the inclination. Reference numeral 37 denotes an exhaust gas containing ash which is introduced into the ash melting furnace main body 27 through the pre-combustion chamber 16.

Next, the operation will be described. Pre-combustion chamber 16
The exhaust gas 37 that has passed through is extremely high temperature of about 1500 ° C. The temperature inside the ash melting furnace body 27 is higher as it is closer to the pre-combustion chamber 16, and conversely, it is lower as it is closer to the slag discharge port 31. Therefore, when the ash melting furnace 20 is used for a long period of time, the closer to the pre-combustion chamber 16, the more severely the furnace inner wall 27d is damaged. Conventionally, heat-resistant bricks or irregular castable refractories were used for the furnace, and the inner wall was formed with a cementing structure. A total repair of 27d was required.

However, by connecting a plurality of ceramic cylindrical tubes 27e, which are sintered bodies containing silicon carbide (SiC) as a main component, with the engaging projections 35 and the engaging recesses 36, the connectivity at the connecting portions is improved. As a result, the molten slag 21 is less likely to accumulate, so that the furnace inner wall 27d is less likely to be damaged.
Repair can be easily completed only by replacing the ceramic cylindrical tube 27e, which is a sintered body mainly containing silicon carbide (SiC) having d. Further, since the high-temperature molten slag 21 flows through the bottom of the furnace inner wall 27d, the bottom is more severely damaged than the upper part. In such a case as well, only the ceramic cylindrical tube 27e, which is a sintered body containing silicon carbide (SiC) as a main component and has the severely damaged furnace inner wall 27d, is rotated by 180 degrees around the center axis, and the undamaged upper portion is moved to the bottom portion. Can be easily and quickly repaired, and can be dealt with effectively without supplementing new repair parts. Note that the other basic operations are the same as those in the first embodiment, and a description thereof will not be repeated.

As described above, according to the second embodiment, the furnace is excellent in corrosion resistance and heat resistance, can start and stop the furnace in a short time, and can divide a plurality of silicon carbide (SiC). By connecting the ceramic cylindrical tube 27e, which is a sintered body containing ()) as the main component, with the engagement convex portion 35 and the engagement concave portion 36, the connection at the connection portion is improved, and the molten slag 21 is less likely to accumulate. Furnace inner wall 27
The effect that hardly causes damage to d is obtained. Even if the furnace inner wall 27d is damaged, only the ceramic cylindrical tube 27e, which is a sintered body containing silicon carbide (SiC) as a main component and has the damaged furnace inner wall 27d, is replaced, or the center axis is changed. The effect that the repair can be easily and quickly performed only by rotating it around 180 degrees is obtained.
Further, the body of the ash melting furnace main body 27 can be constituted only by the ceramic cylindrical tube 27e which is a sintered body mainly composed of silicon carbide (SiC) of the same shape, and form the mold of the ceramic cylindrical tube 27e. Is easy and economical, so mass production is easy and the ash melting furnace body 27
The whole can be easily manufactured, and the effect of reducing the cost can be obtained.

Embodiment 3 FIG. 5 is a sectional view showing an ash melting furnace according to Embodiment 3 of the present invention. In FIG. 5, 27f denotes silicon carbide (Si) having different inner diameters.
C) is a ceramic cylindrical tube which is a sintered body mainly composed of C), and is made of ceramic SiC having the same corrosion resistance and heat resistance as the material used in the first embodiment. Each engagement recess 36 has an inner diameter with which the longitudinal end of each adjacent ceramic cylindrical tube 27f engages. That is, the ash melting furnace main body 27 has a longitudinal end of a ceramic cylindrical tube 27f which is a sintered body containing silicon carbide (SiC) as a main component such that the inner diameter increases from one end in the longitudinal direction to the other end. The portion is connected to the engaging recess 36 of the adjacent ceramic cylindrical tube 27f, which is a sintered body containing silicon carbide (SiC) as a main component, and is installed so that the central axis is horizontal.

Next, the operation will be described. Since the ceramic cylindrical tubes 27f, which are sintered bodies mainly containing silicon carbide (SiC) having different inner diameters, are connected as described above, the furnace inner wall 27d of the ash melting furnace main body 27 faces the slag discharge port 31. It is descending in steps. Therefore, the molten slag 21 tends to stay on the stepped inner wall 27d,
The residence time in the furnace increases, and the melting is performed more reliably. Other basic operations are the same as those in the first embodiment, and a plurality of dividable silicon carbide (Si
Ceramic cylindrical tube 2 which is a sintered body mainly composed of C)
The basic operation using 7f is described in the second embodiment.
The description is omitted because it is the same as in the case of.

As described above, according to the third embodiment, the same effects as those of the first and second embodiments can be obtained.
d is easily retained, and an effect that the ash can be more reliably melted is obtained.

Embodiment 4 FIG. FIG. 6 is a sectional view showing an ash melting furnace according to Embodiment 4 of the present invention. In FIG. 6, 27 g is made of ceramics SiC having the same corrosion resistance and heat resistance as the material used in Embodiment 1 described above. It is a ceramic taper tube (ceramic tube) which is a sintered body containing silicon carbide (SiC) as a main component. As described above, the ash melting furnace main body 27 is made of a plurality of silicon carbide (SiC).
Ceramic taper tube 27 which is a sintered body mainly composed of
g is connected by the engagement convex portion 35 and the engagement concave portion 36 so that the overall shape is formed in a truncated cone shape, and the end plates 27b and 27c are fixed to the heat insulating material 26 so that the central axes thereof are horizontal. . The basic operation is the same as that of the first embodiment, and a ceramic taper tube 27g, which is a sintered body mainly composed of a plurality of dividable silicon carbide (SiC).
Are the same as those in the second embodiment, and a description thereof will be omitted.

As described above, according to the fourth embodiment, the ash can be efficiently and surely melted by a simple structure with excellent corrosion resistance and heat resistance, and the furnace can be started and lowered in a short time. In addition, the furnace inner wall 27d is less likely to be damaged, and even if damage is caused, only the portion concerned can be easily and quickly repaired.

Embodiment 5 FIG. FIG. 7 is a sectional view showing an ash melting furnace according to Embodiment 5 of the present invention. In FIG. 7, reference numeral 27h is made of ceramic SiC having the same corrosion resistance and heat resistance as the material used in Embodiment 1 described above. A ceramic taper tube (ceramic tube) 38, which is a sintered body mainly containing silicon carbide (SiC), protrudes at one longitudinal end of a ceramic tapered tube 27h, which is a sintered body mainly containing silicon carbide (SiC). The provided engagement taper portion 38 b is an engagement taper portion recessed at the other end so as to engage with the engagement taper portion 37.

Next, the operation will be described. When the ceramic taper tube 27h, which is a sintered body containing silicon carbide (SiC) as a main component, expands and contracts due to high-temperature heat, even if the reduced re-slag enters between the engagement taper portions 38a and 38b,
When the ceramic tapered tube 27h, which is a sintered body containing silicon carbide (SiC) as a main component, extends, the slag is scraped out while the engagement tapered portions 38a, 38b abut against each other, whereby clogging of the slag can be reduced. Note that the other operations are the same as those in the above-described fourth embodiment, and a description thereof will not be repeated.

As described above, according to the fifth embodiment, the same effects as those of the fourth embodiment can be obtained, and the engagement tapered portions 38a and 38b are provided.
When the ceramic tapered tube 27h, which is a sintered body containing silicon carbide (SiC) as a main component, extends, the engaging tapered portions 38a and 38b scrape out slag while abutting each other, thereby reducing clogging of the connecting portion with slag. Is obtained.

As shown in FIG. 8, silicon carbide (S
The same effect as in the fifth embodiment can be obtained even if the positions where the engagement tapered portions 38a and 38b are formed in the ceramic tapered tube 27h, which is a sintered body mainly composed of iC), are changed. Here, FIG. 8 is a sectional view showing the ash melting furnace in which the position where the engagement taper portion is formed is changed.

Embodiment 6 FIG. FIG. 9 is a sectional view showing an ash melting furnace according to Embodiment 6 of the present invention, and FIG. 10 is a side view of FIG. 9. In FIGS. A lid-like container (urging means) that is slidably closed in the longitudinal direction of the furnace body 27;
A heat insulating material 41 is provided on the inner surface. The heat insulating material 41 is formed of the same material as the heat insulating material 26,
c is fixed. Reference numeral 42 denotes a sliding portion serving as a sliding surface; 43, a pressing plate (biasing means) fixed to the longitudinal end of the lid-like container 40; 44, a pressing plate fixed to the longitudinal end of the heat insulating container 24. (Urging means), 45 are pressing plates 43, via a disc spring (urging means) 46 having a predetermined
A tie rod (biasing means) connecting the tie rods 44. In addition,
Other configurations are almost the same as those in the above-described fourth embodiment, and a description thereof will not be repeated.

Next, the operation will be described. As described above, the ceramic tapered tube 27g, which is a sintered body containing silicon carbide (SiC) as a main component, is formed so as to be divided by the engaging projections 35 and the engaging recesses 36. Is filled with molten slag 21 and silicon carbide (Si)
Due to the difference in the coefficient of thermal expansion between the ceramic tapered tube 27g, which is a sintered body containing C) as a main component, and the slag, a groove may be formed at the portion, and the discharge of the molten slag 21 may not proceed smoothly. Further, the molten slag 21 may enter the solidified portion to be solidified, and may damage the ceramic tapered tube 27g, which is a sintered body mainly containing silicon carbide (SiC).

For example, the axial length of the ceramic tapered tube 27g, which is a sintered body containing silicon carbide (SiC) as a main component, is 1400 mm, and the temperature of the furnace inner wall 27d is 1350.
When the temperature is set to ° C., the elongation due to thermal expansion reaches about 8.4 mm, which causes the above-mentioned breakage. Therefore, the connectivity between the ceramic tapered tubes 27g, which are sintered bodies containing silicon carbide (SiC) as the main components, is enhanced to smoothen the flow of the molten slag 21, and the molten slag 21 enters the above-mentioned joint. In order to effectively prevent the ceramic taper tube 27g, which is a sintered body containing silicon carbide (SiC) as a main component, from being hardened by solidification, the above-described configuration is employed.

That is, the lid-shaped container 40 is
The ash melting furnace main body 2 is constantly urged by the tie rod 45 and the disc spring 46 with a predetermined pressing force in the direction of the pressing plate 44.
7 always receives the pressing force. Therefore, even if the ash melting furnace main body 27 thermally expands in the longitudinal direction, the connectivity between the ceramic tapered tubes 27g, which are sintered bodies containing silicon carbide (SiC) as a main component, does not decrease, and the bonding portion has Grooves are formed to hinder the flow of the molten slag 21 and to effectively prevent the molten slag 21 from entering the joint and solidifying. Note that the other basic operations are the same as those in the above-described fourth embodiment, and a description thereof will not be repeated.

As described above, according to the sixth embodiment, even if the ash melting furnace main body 27 thermally expands in the longitudinal direction, the ceramic taper which is a sintered body containing silicon carbide (SiC) as a main component. The connectivity between the tubes 27g does not decrease, and a groove is formed in the connection portion to prevent the flow of the molten slag 21,
The effect is obtained that the molten slag 21 can be effectively prevented from entering the joint and solidifying.

In the first to sixth embodiments described above, the case where the heat insulating space including the ash melting furnace main body is provided has been described. However, as shown in FIGS. , Communicates with the inside of the ash melting furnace body,
Even when the heat insulating space including the ash melting furnace main body is not used as the secondary fuel chamber, the same effects as in the first to sixth embodiments can be obtained.

[0056]

As described above, according to the present invention, the main body of the ash melting furnace is made of a ceramic tube which is a sintered body mainly composed of a single silicon carbide (SiC) having heat resistance and corrosion resistance. The ash is formed into a slag without reacting with the CaO component of the ash at a high temperature, and the damage to the inner wall of the furnace can be effectively prevented. Further, since the ceramic tube has high spalling resistance, the furnace is started up. This has the effect that the fall can be performed in a short time.

According to the present invention, the ash melting furnace main body is formed by connecting a plurality of ceramic tubes, which are sintered bodies mainly containing silicon carbide (SiC) having heat resistance and corrosion resistance, and are formed. It has excellent corrosion resistance and heat resistance, can start up and shut down the furnace in a short time, and even if the inner wall of the furnace is damaged, the main component is silicon carbide (SiC) having the damaged inner wall of the furnace. There is an effect that repair can be easily and quickly performed simply by replacing the ceramic tube, which is a sintered body, or rotating the ceramic tube by 180 degrees around the central axis.

According to the present invention, the entire shape of the ash melting furnace main body is formed in the shape of a truncated cone, the ash supply section is provided on the inner wall portion where the inner diameter of the ash melting furnace main body is minimized, and the ash melting furnace main body is provided. Since the slag discharge part is provided at the bottom of the inner wall where the inner diameter of the ash melting furnace is the largest, a large heat transfer area can be secured as compared with the case where the ash melting furnace main body is formed in a cylindrical shape, and the ash melting furnace main body or the heat insulating container The molten slag can be efficiently flowed and discharged by a simple structure without the necessity of being installed at an angle.

According to the present invention, the entire shape of the ash melting furnace main body is formed into a cylindrical shape, the ash melting section is provided with an ash supply section on the inner wall portion at one longitudinal end of the ash melting furnace main body, A slag discharge portion is provided at the bottom of the inner wall at the other end in the direction, and the ash melting furnace main body is inclined so that the slag discharge portion is located at a lower portion of the inclination.
It is easy and economical to manufacture a ceramic tube formwork that is a sintered body containing C) as a main component, and has an effect that the cost of the ash melting furnace main body can be reduced.

According to the present invention, there is provided a sintered body mainly composed of a plurality of silicon carbides (SiC) having different inner diameters so that the inner diameter of the ash melting furnace main body increases from one end in the longitudinal direction to the other end. An ash supply unit is provided on the inner wall of a ceramic cylindrical tube which is a sintered body mainly composed of silicon carbide (SiC) having a minimum inner diameter by connecting ceramic cylindrical tubes, and silicon carbide (SiC) having a maximum inner diameter. Since the slag discharge part is provided at the bottom of the inner wall of the ceramic cylindrical tube, which is a sintered body mainly composed of), the molten slag easily stays on the stepped inner wall of the furnace, and the ash can be more reliably melted. effective.

According to the present invention, silicon carbide (SiC)
Protrusions or engagement protrusions that can engage with each other at the ends to be connected of a ceramic tube, which is a sintered body mainly composed of silicon, and another ceramic tube, which is a sintered body mainly composed of silicon carbide (SiC). Since any one of the mating concave portions is provided, the ceramic tube, which is a sintered body containing silicon carbide (SiC) as a main component, is connected by the engaging convex portion and the engaging concave portion to form the connecting portion. In this case, there is an effect that the molten slag hardly accumulates and the furnace inner wall is hardly damaged.

According to the present invention, the engaging convex portion and the engaging concave portion are each formed in a tapered shape to form the engaging tapered portion, so that the ceramic tube which is a sintered body containing silicon carbide (SiC) as a main component. When the connecting taper extends, the slag is scraped out while the engaging tapered portions abut against each other, and there is an effect that slag clogging at the connecting portion can be reduced.

According to the present invention, the ash melting furnace main body is provided with the urging means for urging at least one of both ends in the longitudinal direction of the ash melting furnace body inward, so that the ash melting furnace main body is thermally expanded in the longitudinal direction. However, the bondability between the ceramic pipes, which are sintered bodies containing silicon carbide (SiC) as a main component, does not decrease, and a groove is formed at the connection portion to hinder the flow of the molten slag, There is an effect that it is possible to effectively prevent entry into the connection portion and solidification.

According to the present invention, the first to sixth embodiments can be communicated with the inside of the ash melting furnace main body, even when the heat insulating space containing the ash melting furnace main body is not used as the secondary heating chamber. Has the same effect as.

[Brief description of the drawings]

FIG. 1 is a principle diagram schematically showing a system using an ash melting furnace according to Embodiment 1 of the present invention.

FIG. 2 is a vertical sectional view showing an ash melting furnace.

FIG. 3 is a sectional view showing an ash melting furnace according to Embodiment 2 of the present invention.

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

FIG. 5 is a sectional view showing an ash melting furnace according to Embodiment 3 of the present invention.

FIG. 6 is a sectional view showing an ash melting furnace according to Embodiment 4 of the present invention.

FIG. 7 is a sectional view showing an ash melting furnace according to Embodiment 5 of the present invention.

FIG. 8 is a cross-sectional view showing the ash melting furnace in which the position where the engagement taper portion is formed is changed.

FIG. 9 is a sectional view showing an ash melting furnace according to Embodiment 6 of the present invention.

FIG. 10 is a side view of FIG. 9;

FIG. 11 is a cross-sectional view showing an ash melting furnace without an adiabatic space including an ash melting furnace main body.

FIG. 12 is a sectional view taken along line BB of FIG. 11;

FIG. 13 is a principle view showing a waste incineration system disclosed in Japanese Patent Publication No. 1-52654.

[Explanation of symbols]

1 Fluidized bed gasifier (furnace facility), 11 fly ash (ash), 21 molten slag, 24 insulated vessel, 25 gas outlet (exhaust part), 27 ash melting furnace main body, 27a ceramic taper tube (single Ceramic tube), 27d Furnace inner wall (inner wall), 27e Ceramic cylindrical tube (ceramic tube), 27f Ceramic cylindrical tube, 27g, 2
7h Ceramic taper tube (ceramic tube), 28
Secondary combustion chamber (insulated space), 29 fly ash supply nozzle (ash supply section), 31 slag discharge port (slag discharge section), 35
Engagement convex portion, 36 Engagement concave portion, 38a, 38b Engage taper portion, 40 Lid-shaped container (urging means), 43, 44 Press plate (urging means), 45 Tie rod (urging means), 4
6 Belleville spring (biasing means).

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tetsuya Nishizu 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Inside Mitsubishi Electric Corporation (72) Inventor Kazuhiko Kawajiri 2-3-2, Marunouchi, Chiyoda-ku, Tokyo Rishi Electric Co., Ltd. (72) Inventor Tetsuya Honda 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Hiroaki Shigeoka 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric (72) Inventor Takashi Yonezawa 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (9)

[Claims] An insulated container having an ash melting furnace body for introducing ash generated in a furnace facility, heating and melting the same, and discharging the slag as molten slag, and an exhaust unit for communicating the inside of the ash melting furnace body with the outside air. In the ash melting furnace provided with the above, the ash melting furnace main body is made of a single silicon carbide (S) having heat resistance and corrosion resistance.
An ash melting furnace formed of a ceramic tube which is a sintered body containing iC) as a main component. 2. An ash melting furnace main body for introducing and melting the ash generated in the furnace facility by heating and melting and discharging the molten slag, and an insulating space which communicates with the inside of the ash melting furnace main body and includes the ash melting furnace main body. In the ash melting furnace having the heat insulating space and the heat insulating container having the exhaust part for communicating the outside air with the heat insulating space, the ash melting furnace body is made of a single silicon carbide (SiC) having heat resistance and corrosion resistance. An ash melting furnace characterized by being formed of a ceramic tube which is a sintered body having a main component. 3. An ash-melting furnace main body for introducing and melting ash generated in a furnace facility, and heating and melting the ash-melted slag to discharge as molten slag, and an insulating space that communicates with the inside of the ash-melting furnace body and includes the ash-melting furnace main body. An ash melting furnace comprising a heat insulating container having an exhaust part for forming and communicating the heat insulating space with the outside air, wherein the ash melting furnace main body is mainly made of silicon carbide (SiC) having heat resistance and corrosion resistance. An ash melting furnace characterized in that a plurality of sintered ceramic tubes, which are sintered bodies, are connected and formed. 4. An ash-melting furnace main body having a truncated conical shape as a whole, and an ash supply unit for introducing ash into an inner wall of the ash-melting furnace body having a minimum inner diameter. The ash melting furnace according to any one of claims 1 to 3, wherein a slag discharge portion for discharging molten slag is provided at a bottom portion of the inner wall where an inner diameter of the slag is maximum. 5. The ash melting furnace main body is formed in a cylindrical shape as a whole, and an ash supply unit for introducing ash is provided on an inner wall portion at one longitudinal end of the ash melting furnace main body. A slag discharge part for discharging molten slag is provided at the bottom of the inner wall at the other end in the direction, and the ash melting furnace main body is inclined such that the slag discharge part is located at a lower part of the inclination. 4. The ash melting furnace according to any one of 3 above. 6. A ceramic cylindrical tube which is a sintered body mainly composed of a plurality of silicon carbides (SiC) having different inner diameters so that the inner diameter of the ash melting furnace main body increases from one end in the longitudinal direction to the other end. An ash supply unit for introducing ash is provided on the inner wall of a ceramic cylindrical tube which is a sintered body mainly composed of silicon carbide (SiC) having a minimum inner diameter and has a maximum inner diameter. 4. The ash melting furnace according to claim 3, wherein a slag discharge portion for discharging molten slag is provided at a bottom portion of an inner wall of a ceramic cylindrical tube which is a sintered body having (1) as a main component. 7. A ceramic tube which is a sintered body containing silicon carbide (SiC) as a main component and another silicon carbide (SiC)
5. An end portion to be connected of a ceramic tube, which is a sintered body mainly composed of: one of an engaging convex portion and an engaging concave portion which can be engaged with each other, is provided. The ash melting furnace according to claim 6. 8. An engaging tapered portion, wherein each of the engaging convex portion and the engaging concave portion is formed in a tapered shape.
The ash melting furnace as described. 9. An urging means for urging at least one of both longitudinal end portions of the ash melting furnace main body inward in order to regulate expansion and contraction of the ash melting furnace main body in the longitudinal direction based on a temperature change. 9. The method according to claim 7, wherein
The ash melting furnace as described.