JP2001012722A - Heating/melting processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating/melting processing apparatus having a structure wherein molten slag of a burned residue can be stably taken out, and a constituent member around an outlet can be prolonged in its life. SOLUTION: There are provided a cooling tube 6 for cooling a refractory member 3 around an outlet 9 through which molten slag 5 flows out, and a heater 7 for heating the molten slag 5 around the outlet 9. The heater 7 is graphite coated with SiC, a conductive MoSi2 composite sintered structure, a conductive ZrB2 composite sintered structure, or ones enclosed with a non- conductive refractory member, and is excellent in non-oxydation and slag resistant. The molten slag 5 is continuously stably taken out owing to heat of the heater 7 at the outlet 9. In contrast, a self-coating layer 10 is for med in which slag is solidified on an internal wall of the outlet 9, whereby the internal wall of the outlet 9 and the molten slag 5 are prevented from directly making contact with each other, and hence the refractory member 3 is prevented from being melted for its long time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating and melting treatment apparatus, and more particularly to a heating and melting treatment apparatus for reducing the volume and detoxifying incineration residues such as municipal waste and sewage sludge.

[0002]

2. Description of the Related Art At present, wastes such as garbage discharged from homes and sludge generated in sewage treatment are incinerated, and the generated residues are landfilled. However, as landfills are depleted, environmental pollution such as dioxins and heavy metals has become a problem.

As an effective means for solving these problems at the same time, a heating and melting treatment apparatus for melting incineration residues to form slag has been developed.

[0004]

The heating and melting treatment methods are roughly classified into a combustion heating method and an electric heating method. In any of the methods, there is a problem that the molten slag can be stably discharged and how long the life of the components around the discharge port can be extended.

[0005] Regarding the stable slag of the molten material, see Japanese Utility Model Application Laid-open No.
No. 7595 discloses a technique for heating the periphery of a slag outlet with an auxiliary electrode. In this technology, the graphite of the electrode material
Since it is oxidized and consumed, it needs to be replaced at regular intervals.
Japanese Patent Publication No. 5-30517 proposes a technique in which the periphery of a slag outlet is made of conductive ceramics and induction heating is performed. With this technique, oxidation resistance is improved, but 1400 ° C.
Above, the conductive ceramics elutes into the molten slag,
In order to wear out, replacement is also required at regular intervals.

On the other hand, regarding the prolongation of the service life of the components around the slag outlet, Japanese Patent Application Laid-Open Nos.
Japanese Unexamined Patent Publication No. 159440 discloses a technique for cooling a non-conductive refractory material constituting an inner wall of a slag port from the inside and forming a solidified layer of slag on the inner wall of the slag port to protect the refractory material. However, the amount of slag from the molten slag is affected by the temperature of the solidified slag layer, and the thermal conductivity between the molten slag and the refractory material is low. Have difficulty.

An object of the present invention is to provide a heating and melting treatment apparatus having a structure capable of stably removing molten slag from incineration residues and extending the life of constituent members around the discharge port.

[0008]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides a heating and melting apparatus for heating and melting a solid and / or a powder. Provided in the, around the entrance of the slag port is made of non-conductive refractory material, comprising means for cooling the refractory material from the inside,
We propose a heating and melting treatment device in which a heating element is provided around the outlet of the slag outlet.

According to the present invention, there is further provided a heating and melting treatment apparatus for heating and melting a solid and / or powder, wherein a slag outlet through which a molten material flows is provided at the bottom of the melting furnace, and the periphery of the slag outlet is electrically non-conductive. The present invention proposes a heating and melting treatment apparatus comprising a refractory material having a means for cooling the refractory material from the inside, and a heating element and a non-conductive refractory material around the outlet of the slag port.

According to the present invention, there is further provided a heating and melting treatment apparatus for heating and melting a solid and / or powder, wherein a slag outlet through which a melt flows out is provided at the bottom of the melting furnace, and a heating element is provided around the entrance of the slag opening. And a means for cooling the refractory material from the inside, and comprising a heating element around the outlet of the slag outlet.

In any of the heating and melting treatment apparatuses, it is desirable that the hole at the outlet of the slag port is wider than the hole at the entrance of the slag port.

According to the present invention, in a heating and melting treatment apparatus for heating and melting a solid and / or powder, a slag outlet from which a melt flows out is provided at the bottom of a melting furnace, and a periphery from an inlet to an outlet of the slag outlet is provided. The present invention proposes a heating and melting treatment apparatus which is composed of a heating element and a non-conductive refractory material and has means for cooling the refractory material from the inside.

According to the present invention, there is also provided a heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag outlet through which a melt flows out is provided at the bottom of the melting furnace, and the periphery of the slag outlet is electrically non-conductive. And a means for cooling the refractory material from the inside, and a heating and melting treatment apparatus in which a heating element is inserted and installed in the hole of the slag port is proposed.

According to the present invention, in order to achieve the above object, in a heating and melting treatment apparatus for heating and melting a solid and / or powder, a slag outlet from which a melt flows out is provided at the bottom of a melting furnace. The heating element that forms the periphery of the entrance of the furnace is protruded into the furnace and installed. The side of the heating element and the top surface of the heating element that do not form the slag port are covered with a nonconductive refractory material. The present invention proposes a heating and melting treatment apparatus provided with means for extending the refractory material so as to cover the upper surface of the slag outlet and cooling the non-conductive refractory material from the inside.

According to the present invention, there is provided a heating and melting treatment apparatus for heating and melting a solid and / or a powder. The present invention proposes a heating and melting treatment apparatus comprising a means for cooling a refractory material from the inside, comprising a heating element at a position facing the outlet of the slag port and away from the outlet.

According to the present invention, there is also provided a heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag port through which a melt flows out is provided on a side wall of the melting furnace, and a lower side of the slag port is nonconductive. The present invention proposes a heating and melting treatment apparatus comprising a refractory material having a means for cooling the refractory material from the inside and a heating element provided on the upper side of the slag port.

In this heat melting apparatus, a heating element can be provided at a position facing the outlet of the slag port and away from the outlet.

In any of the above-mentioned heat melting apparatuses, the heating element is made of graphite coated with silicon carbide,
Conductive ceramics containing a metal boride, conductive ceramics containing a metal silicide, graphite or a non-conductive refractory material containing the conductive ceramics.

Further, the refractory material constituting the periphery of the slag port is as follows:
It is made of ceramics containing zirconium boride or molybdenum silicide.

Further, the cooling means is means for cooling the refractory material with the refrigerant, means for controlling the flow rate of the refrigerant of the cooling means, means for controlling the amount of heat generated by the heating element, and means for cooling the non-conductive refractory material. A temperature measuring means installed inside the heating element, a temperature measuring means installed inside or near the heating element, and a means for controlling the flow rate of the refrigerant and the heating value of the heating element based on the measured temperatures. be able to.

In this case, there is provided a monitoring device for monitoring the condition of the outlet of the slag outlet in a non-contact manner, and means for controlling the flow rate of the refrigerant and the calorific value of the heating element based on the status of the slag port obtained by the monitoring device. May be provided.

In the present invention, the molten slag flows down along the surface of the solidified layer formed by cooling, so that contact between the molten slag and the refractory material can be prevented, and erosion of the refractory material can be prevented. In this case, since the slag itself is used as a protective layer of the refractory material, in the present specification, this action is called self-coating.

On the other hand, the temperature of the molten slag decreases in the process of flowing down from the inside of the melting furnace through the slag port, the viscosity increases, and furthermore, the molten slag solidifies and becomes clogged.

Therefore, in the present invention, a heating means is provided around the slag outlet to heat the slag so that the slag can be stably extracted.

The thickness of the self-coating layer changes in response to changes in temperature and the amount of molten slag. However, when the cooling means and the heating means in the vicinity of the slag port are controlled, respectively, The thickness can be maintained at a predetermined value, and the molten slag can be stably discharged continuously.

In the peripheral structure of the slag outlet, the hole diameter of the outlet is larger than that of the inlet of the slag outlet. Thereby, contact between the heating element and the molten slag can be prevented, and melting of the heating element by the molten slag can be prevented.

Although the temperature of the refrigerant is low at the inlet of the cooling pipe, the temperature rises due to heat exchange and becomes high at the outlet. Therefore, the high temperature part of the inner pipe and the low temperature part of the outer pipe or the low temperature of the inner pipe are caused by the counterflow. The part and the high temperature part of the outer tube are made uniform by heat conduction. Counterflow can also be realized with a structure in which the cooling pipe is folded around the slag port.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, referring to FIGS.
An embodiment of the heating and melting treatment apparatus according to the present invention will be described. For example, in the case of an electric heating method, any one of an electric resistance heating method, an arc discharge heating method, and an electromagnetic induction heating method may be used as the melting heat treatment method. Here, an example of the electromagnetic induction heating type will be described.

Embodiment 1 FIG. 1 is a system diagram showing a system configuration of Embodiment 1 of a heating and melting treatment apparatus according to the present invention in which a slag port is provided at the bottom. In the first embodiment, a slag port 8 through which a molten material, that is, a molten slag 5 flows out, is provided at the bottom of the melting furnace 1, and the periphery of the entrance of the slag port 9 is made of a non-conductive refractory material 3. A means 6 for cooling from the inside was provided, and a heating element 7 was formed around the outlet of the slag port 9.

The electromagnetic induction heating furnace 1 comprises a melting furnace coil 2
And the refractory material 3 which is arranged inside and forms a furnace body
Consists of A slag port 9 for discharging the melt-processed slag 5 is formed at the bottom of the furnace, and the furnace is filled with graphite 4 as a conductive substance.

The high frequency power supply 14 for the melting furnace energizes the coil 2 for the melting furnace, generates a magnetic field, and heats the graphite 4 by induction. Since the melting furnace coil 2 generates heat when energized, it is made of a copper tube, and water is passed through to cool and protect it.

The ash supplied from the supply port 11 is heated in the furnace, melts on the surface of the graphite 4, flows down in the furnace, becomes molten slag 5, and is discharged from the slag port 9. The molten exhaust gas is
Through the discharge port 12, it is subjected to dust removal and harmless treatment, and is discharged to the atmosphere.

Since the outlet of the slag port 9 is a boundary between the inside of the furnace and the outside air, the temperature of the molten slag 5 passing through the outlet tends to decrease, the viscosity increases, the fluidity deteriorates, and the molten slag 5 further solidifies. Close the outlet.

In the present invention, the molten slag 5 in the lower part of the furnace is reduced by about 14 to stably discharge the molten slag 5.
While maintaining a high temperature of 00 ° C., the molten slag 5 is heated at the outlet of the slag port 9.

As a heating means around the slag port 9, a heating element 7 and a slag port coil 16 for inductively heating the heating element 7 are provided below the slag port 9. Induction heating. The heating element 7 can be heated to the heat resistant temperature of the furnace body refractory material 3.

Since the heating element 7 is in the outside air outside the slag port 9, it is made of a material having excellent oxidation resistance. Further, in order to prevent the heating element 7 from being melted by the molten slag 5, a material having excellent slag resistance is employed, or the hole diameter of the heating element 7 is made larger than the hole diameter of the slag port 9.

As the refractory material 3 in the slag port, heat resistance,
Uses alumina-based refractory material with excellent slag resistance. 14
In a high temperature environment of 00 ° C., the refractory material 3 elutes in a small amount to the molten slag 5 side, so that the refractory material 3 is cooled by the cooling pipe 6, and a solidified slag layer, that is, a self-coating layer 10 is formed on the surface of the refractory material 3. Is formed.

The self-coating layer 10 serves as a protective layer to prevent direct contact between the refractory material 3 and the molten slag 5 and prevent the refractory material 3 from being melted.

Since the thickness of the self-coating layer 10 varies depending on the surface temperature of the refractory material 3 at the slag outlet, the heating element 7 must be used to keep the thickness of the self-coating layer 10 constant.
And the amount of heat removed from the cooling pipe 6 are controlled.

The amount of heat generated by the heating element 7 is controlled by the output power of the high frequency power supply 15 for the slag outlet, and the amount of heat removed from the cooling pipe 6 is controlled by the refrigerant flow rate of the flow rate adjusting means 17.

As described above, the molten slag is continuously and stably discharged by heating at the bottom of the furnace and at the outlet of the slag outlet, and the refractory material 3 around the slag outlet 9 is extended in life by cooling.

However, these operations are, in terms of energy, opposing operations of heating and cooling. Therefore, the amount of heat removed from the cooling pipe 6 and the power applied to the heating element 7 are minimized to save energy.

First, since the self-coating layer 10 is formed at a temperature lower than the melting point of the molten slag 5, the inner wall temperature of the slag port 9 is set at a temperature lower than the melting point of the molten slag 5. Molten slag 5
Has different melting points depending on the components. Since the melting point of refuse incineration ash and sewage sludge incineration ash is about 1200 ° C., the inner wall temperature of the slag port 9 is controlled to about 1100 ° C.

It is possible to pass any one of only water, only air, and a mixture of mist-like water and air into the cooling pipe 6.

When the refrigerant is air, the specific heat per unit volume is 1 / 10,000 of water, and the amount of heat removed is small, but a small amount can be adjusted.

When a mixture of mist-like water and air is used as a refrigerant, a larger amount of heat can be secured than in the case of air, and a small amount of heat can be adjusted by adjusting the amount of air.

Further, when the temperature of the inlet of the refrigerant is lowered by the cooler 22, the heat removal amount can be increased.

Here, the controllability will be emphasized, and the refrigerant will be described as air.

When the cooling pipe 6 is a SUS pipe, the cooling pipe 6 is used at 700 ° C. or lower to prevent oxidation. If the cooling pipe 6 is installed away from the inner wall of the slag port 9, slow temperature control will be performed. If the cooling pipe 6 is installed close to the inner wall of the slag port 9, the surface temperature of the cooling pipe 6 will be insufficient due to insufficient heat removal. May be 700 ° C. or higher. Desirably, the distance between the cooling pipe 6 and the inner wall of the slag port 9 is 30 mm to 50 mm, and the inner wall temperature of the slag port 9 is maintained at about 1100 ° C. while the surface temperature of the cooling pipe 6 is maintained at 700 ° C. or less. .

Further, a cooling pipe temperature measuring device 20 is installed at a place where the surface has the highest temperature, the temperature is monitored, and the cooling pipe 6 is measured.
Prevents oxidation of the entire surface.

In this case, the temperature control device 18 further includes
The monitor device 23 remotely monitors the thickness of the self-coating layer 10 and the slag condition, and predicts the inner wall temperature of the slag port 9 based on the temperature information of the cooling pipe temperature measuring device 20 and the heating element temperature measuring device 21. , Flow control means 17, cooling machine 2
2. Control the output of the high frequency power supply 15 for the slag outlet.

<Embodiment 2> FIG. 2 is a diagram showing a main structure of a heating and melting treatment apparatus according to a second embodiment of the present invention in which a slag port is provided at the bottom. In the second embodiment, the slag port 9 through which the melt 5 flows out is provided at the bottom of the melting furnace 1, the periphery of the entrance of the slag port 9 is made of a non-conductive refractory material 3, and the refractory material 3 is cooled from the inside. A heating means 7 and a non-conductive refractory material 3 are provided around the outlet of the slag port 9.

That is, the periphery of the entrance of the slag port 9 is made of the furnace body refractory material 3, the cooling pipe 6 is provided inside the refractory material 3, and the vicinity of the exit of the slag port 9 is the furnace body refractory material 3 and the heating element 7. It consists of

The heating element 7 is energized by a slag outlet DC power supply 30 to perform resistance heating. The molten slag 5 in the furnace is cooled by the inner wall of the slag port 9 to form a self-coating layer 10. The heating element 7 reheats the molten slag whose temperature has decreased and the viscosity has increased, and promotes the flow down. The heating element 7 is made of a material having excellent oxidation resistance, and has a wider outlet than the entrance of the slag port 9 to prevent contact with the molten slag 5 and suppress erosion.

On the surface of the furnace refractory 3 on the right side of the slag port 9,
The self-coating layer 10 that has grown down is formed. The flow rate 17 of the flow rate control means and the output of the slag outlet DC power supply 30 are controlled to maintain the state in which the self-coating layer 10 is formed.

Embodiment 3 FIG. 3 is a diagram showing a main part structure of Embodiment 3 of a heating and melting treatment apparatus according to the present invention in which a slag port is provided at the bottom. In the third embodiment, a slag port 9 through which the melt 5 flows out is provided at the bottom of the melting furnace 1, and the periphery of the entrance of the slag port 9 is composed of a heating element 8 and a non-conductive refractory material 3. Means 6 for cooling the inside 3 was provided, and the periphery of the outlet of the slag outlet 9 was constituted by heating elements 7 and 8.

That is, the furnace body refractory 3, the heating element 7 below the furnace body 3, and the heating element 8 on the opposite side constitute the periphery of the slag port 9. These heating elements 7 and 8 are heated by electromagnetic induction by a coil 16 for a slag port and a high-frequency power supply 15 for a slag port.

The heating element 7 on the lower left side of the slag port 9 is made of a material having excellent slag resistance, and the outlet of the slag port 9 is made wider than the inlet to suppress contact with the molten slag.

The facing heating element 8 is easier to heat the slag than in the second embodiment. However, since the facing-side heating element 8 comes into contact with the molten slag 5, it is made of a material having excellent slag resistance, and the movable support 31 during operation.
Can be moved and exchanged.

Further, since the facing-side heating element 8 is disposed so as to protrude into the melting furnace 1, the temperature is raised by heat conduction from the furnace, and the molten slag 5 can be heated to a high temperature with a small amount of electric power.

Also in this case, the flow rate of the flow rate adjusting means 17 and the output of the high frequency power supply 15 for the slag port are controlled to maintain the state in which the self-coating layer 10 is formed.

<Embodiment 4> FIG. 4 is a view showing a main structure of a heating and melting treatment apparatus according to a fourth embodiment of the present invention in which a slag port is provided at the bottom. In the fourth embodiment, a slag port 9 through which the melt 5 flows out is provided at the bottom of the melting furnace 1, and the periphery from the inlet to the outlet of the slag port 9 is constituted by the heating element 8 and the non-conductive refractory material 3. ,
A means 6 for cooling the refractory material 3 from the inside is provided.

As described in the description of the third embodiment, when the facing-side heating element 8 is installed so as to protrude into the melting furnace 1, the temperature rises due to heat conduction from the furnace, and the molten slag 5 can be heated with little power. In Example 4, the method of increasing the heating amount of the facing-side heating element 8 without providing the lower heating element 7 in Example 3 was adopted.

Also in this case, the flow rate of the flow rate adjusting means 17 and the output of the high frequency power supply 15 for the slag port are controlled to maintain the state in which the self-coating layer 10 is formed.

<Embodiment 5> FIG. 5 is a view showing the structure of a main part of Embodiment 5 of a heating and melting treatment apparatus according to the present invention in which a slag port is provided at the bottom. In the fifth embodiment, a slag port 9 through which the melt 5 flows out is provided at the bottom of the melting furnace 1, the periphery of the slag port 9 is made of a non-conductive refractory material 3, and the refractory material 3 is cooled from the inside. The means 6 was provided, and the heating element 7 was inserted and installed in the hole of the slag port.

The heating element 7 is heated by electromagnetic induction by means of the tapping coil 16 and the tapping high frequency power supply 15. Since the heating element 7 comes into contact with the molten slag 5, it is made of a material having excellent slag resistance. Further, even during operation, the movable support 31
Is moved so that the heating element 7 can be replaced.

The slag outlet coil 16 is hollow, and also has the function of a cooling pipe for cooling water through the slag outlet.

Also in this case, the flow rate of the flow rate adjusting means 17 and the output of the high frequency power supply 15 for the slag port are controlled to maintain the state in which the self-coating layer 10 is formed.

The structure shown in FIG. 5 can be applied to the later-described seventh and eighth embodiments in which the slag port 9 is provided on the side wall of the melting furnace.

<Embodiment 6> FIG. 6 is a diagram showing a main structure of a heating and melting treatment apparatus according to a sixth embodiment of the present invention in which a slag port is provided at the bottom. In the sixth embodiment, a slag port 9 from which the melt 5 flows out is provided at the bottom of the melting furnace 1, and a heating element 8 constituting the periphery of the entrance of the slag port 9 is protruded into the furnace and installed. And the upper surface of the heating element 7 is covered with the non-conductive refractory material 3, and the non-conductive refractory material 3 provided on the upper surface of the heating element 8 is covered with the upper surface of the slag port 9. Means 45 for cooling the non-conductive refractory material 3 from the inside,
46.

FIG. 6 shows a structure in which the facing-side heating element 8 does not come into contact with the molten slag. Face-side heating element 8
The side and upper surface not facing the slag port 9 are covered with the refractory material 3. The refractory material 3 on the upper surface of the facing heating element 8 projects into the furnace so as to cover the upper surface of the slag port 9, and has a furnace internal cooling pipe 45 inside.

Thus, the self-coating layer 10 is formed to protect the refractory material 47 inside the furnace. The molten slag flows from the left side of the slag port 9 and flows down.

Therefore, if the distance between the refractory material 3 of the slag port 9 and the facing-side heating element 8 is adjusted, contact of the facing-side heating element 8 with the molten slag can be avoided.

When the flow rate of the molten slag is small, the position of the facing heating element 8 is adjusted by the movable support 31,
The facing-side heating element 8 is brought closer to the slag port 9 to increase the amount of heat applied to the slag 5.

The output of the flow rate adjusting means 43 and 44 and the output of the high frequency power supply 15 for the slag port are controlled to maintain the state in which the self-coating layer 10 is formed.

<Embodiment 7> FIG. 7 is a system diagram showing a system configuration of an embodiment of a heating and melting treatment apparatus according to the present invention in which a slag outlet is provided on a bottom portion on a side wall. In the seventh embodiment, a slag port 9 through which the melt 5 flows out is provided on the side wall of the melting furnace 1, the periphery of the slag port 9 is made of a non-conductive refractory material 3, and the refractory material 3 is cooled from the inside. Means 6 were provided, and a heating element 7 was provided at a position facing the outlet of the slag outlet 9 and away from the outlet.

Here, the heating method of the melting furnace is described as an electric resistance method. The electric resistance heating furnace 1 includes a furnace body refractory material 3.
And a slag port 9 for discharging the molten slag 5 from the side wall, two graphite electrodes 34 inserted from above the melting furnace 1, an ash supply port 11, and an exhaust gas discharge port 12.

The two graphite electrodes 34 are connected to an AC power supply 35, generate resistance heat using the molten slag 5 as a resistor, and melt the ash at a high temperature by the heat.

In order to protect the inner wall of the refractory material 3 by self-coating, the outer wall is cooled with the furnace body cooling water 36. The inner wall of the slag port 9 is also cooled by the cooling water 36 of the furnace body to form the self-coating layer 10.

When the liquid level of the molten slag 5 is lower than the installation position of the slag port 9, there is no heating source for the slag port 9 and the slag port 9 is not provided.
Closes.

When the liquid level is high, the heating element 7 installed perpendicularly to the hole downstream of the slag port 9 is connected to the slag port DC power supply 30.
To heat the molten slag 5 that has solidified or increased in viscosity, thereby promoting slag removal.

The control device 37 is provided with the temperature measuring device 21 for the heating element.
Controls the power supplied from the slag outlet DC power supply 30 to the heating element 7 based on the measured temperature of the heating element 7.

The heating element 7 is supported by a movable support 31 so that it can move in the lateral direction. When the flow rate of the molten slag 5 is low, the heating element 8 is brought closer to the slag port 9 to increase the amount of heat applied to the slag 5, and when the flow rate of the molten slag is large, the heating element 8 is separated from the slag port 9 so as not to contact. To use. As described above, since it is desirable that the position of the heating element 7 can be controlled according to the situation, the situation can be monitored by the monitor device 23 and controlled based on the situation.

When the outflow of the molten slag is large, the thickness of the self-coating layer 10 is controlled by the cooling pipe 6 because the self-coating layer 10 becomes thin. The flow rate of the refrigerant is controlled by the flow rate adjusting means 17 to maintain the temperature at which the surface of the cooling pipe 6 does not oxidize.

The control device 37 is provided with a cooling pipe temperature measuring device 2.
0, the monitoring device 23, and the information from the temperature measuring device 21 for the heating element, the temperature of the heating element 7 is controlled by the DC power supply 30 for the slag outlet, and the surface temperature of the cooling pipe 6 is controlled by the flow rate adjusting means 17. The position of the heating element 7 is controlled by the movable support 31 so that the molten slag can be continuously and stably discharged.

Since the slag port is a high-temperature atmosphere at 1400 ° C. and is also a place in contact with the atmosphere, it is important that the heating element provided around the slag port 9 has excellent oxidation resistance.

<Eighth Embodiment> FIG. 8 is a view showing a main structure of an eighth embodiment of a heating and melting treatment apparatus according to the present invention in which a slag port is provided on a side wall. In the eighth embodiment, the slag port 9 through which the melt 5 flows out is provided on the side wall of the melting furnace 1, the lower side of the slag port 9 is made of the non-conductive refractory material 3, and the refractory material is cooled from the inside. Means 6 were provided, and a heating element 8 was provided above the slag outlet. Further, a heating element 7 was provided at a position facing the outlet of the slag outlet 9 and away from the outlet.

In the case of the eighth embodiment, since the heating element 8 is also provided on the upper side of the outlet of the slag port 9, the molten slag 5 can be continuously and smoothly slag-discharged.

FIG. 9 is a view showing an example of the structure of a heating element used around the slag outlet of the present invention. The heating element in FIG. 9 is a heating element in which a surface of graphite 25 is coated with silicon carbide SiC 26, which is a non-oxide ceramic, by about 1 mm. The graphite 25 is inexpensive as a heating element, but is in contact with oxygen in the atmosphere and is worn away. Therefore, the graphite 25 is subjected to a surface conversion treatment in a Si gas to form a silicon carbide film 26. The SiC film 26 is oxidized at a high temperature, becomes a SiO ₂ film, and acts as a protective film for the graphite 25.

FIG. 10 is a view showing another example of the structure of the heating element used around the slag port of the present invention. The heating element of FIG. 10 is a heating element including a conductive heating element 25 inside an Al ₂ O ₃ —Cr ₂ O ₃ refractory material 27 that is not oxidized. A
l ₂ O ₃ -Cr ₂ O ₃ based refractory material 27 is also an excellent material less slag resistance of erosion when in contact with molten slag 5. Since the refractory material 3 is a porous material, the graphite 25 is desirably coated with SiC to provide double protection from oxygen intrusion.

FIG. 11 is a view showing another example of the structure of the heating element used around the slag port of the present invention. The heating element in FIG. 11 uses a mixed material 28 of non-oxide ceramics and conductive ceramics as the heating element.

Here, the conductive metal MoSi ₂ and the non-conductive ceramic Al ₂ O ₃ were mixed at a predetermined ratio, and the conductive MoSi ₂ produced by hot pressing was used.
A system-based composite sintered body 28 is employed. The MoSi ₂ -based composite sintered body 28 is a material having excellent slag resistance, like the Al ₂ O ₃ -Cr ₂ O ₃ -based refractory material.

FIG. 12 is a diagram showing the degree of wear of the heating element according to the present invention in comparison with the degree of consumption of the conventional graphite heating element. That is, it is a diagram showing the results of comparing the degrees of wear of the three types of heating elements of FIGS. 9 to 11.

The outline of the procedure of the ash melting test for testing the durability of the slag tap is as follows. First, the inside of the furnace was heated to 1400 ° C. by the electromagnetic induction heating type melting apparatus shown in FIG. After that, the ash was fed at a constant rate of 30 kg / h from a feeder. After the temperature of each part in the furnace became a steady state, the furnace was operated continuously for 20 hours. The rate of decrease was determined. After that, the temperature rises again,
The cycle of running for 20 hours was repeated, and the weight loss rate was evaluated every 20 hours.

As a result, the graphite is significantly oxidized,
At about 40 hours, the shape is reduced so as not to remain. On the other hand, the weight loss of the other three types of heating elements is as small as 10% or less even when the total operation time is 80 hours.

In the test in which these three types were heated in an air atmosphere, there was no weight loss even in the total operation time of 80 hours, and about 10% consumption in the ash melting test can be judged as melting damage to the molten slag. Therefore, if the frequency of contact between the heating element and the molten slag is reduced, the consumption can be further reduced.

A non-conductive ZrB ₂ composite sintered body obtained by mixing and sintering SiC and ZrB ₂ at a predetermined ratio is as follows:
Although it is inferior in oxidation resistance, it is a material that is superior in slag resistance to three types. Since the oxygen concentration is low at the entrance of the slag port 9, it can be used as the refractory member 3.

FIG. 13 is a diagram showing the variation in the amount of slag discharged continuously according to the present invention in comparison with the variation in the conventional intermittent slag. The temperature of the conventional molten slag 5 decreases in the process of flowing down from the inside of the melting furnace 1 through the slag port 9,
The viscosity increased and further solidified, leading to blockage, resulting in intermittent scum.

On the other hand, in the present invention, the molten slag 5 can be continuously and stably discharged by the heat of the heating element 7 at the outlet of the discharge port 9. On the other hand, the self-coating layer 10 in which the slag is solidified on the inner wall of the slag port 9 by cooling from the cooling pipe 6.
Is formed, and the direct contact between the inner wall of the slag port 9 and the molten slag 5 is avoided, so that the refractory material 3 is prevented from being melted and the service life can be extended.

[0100]

According to the present invention, a self-coating layer is formed on the refractory material constituting the inner wall of the slag port, so that the refractory material is prevented from being melted into the molten slag and the life of the refractory material can be extended.

Further, a material having excellent oxidation resistance and slag resistance is used for the heating element for heating the periphery of the slag outlet, and the heating element has a structure that does not easily come into contact with the molten slag. Can be

Furthermore, as a result of extending the life of both the refractory material and the heating element constituting the periphery of the slag outlet, the molten slag can be ashed almost continuously.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a system configuration of a first embodiment of a heating and melting treatment apparatus according to the present invention in which a slag port is provided at a bottom portion.

FIG. 2 is a view showing a main structure of a second embodiment of the heating and melting treatment apparatus according to the present invention, in which a slag port is provided at a bottom portion.

FIG. 3 is a diagram showing a main part structure of a third embodiment of the heating and melting treatment apparatus according to the present invention, in which a slag port is provided at the bottom.

FIG. 4 is a diagram showing a main structure of a fourth embodiment of the heating and melting treatment apparatus according to the present invention, in which a slag port is provided at the bottom.

FIG. 5 is a diagram showing a main part structure of a fifth embodiment of the heating and melting treatment apparatus according to the present invention in which a slag port is provided at the bottom.

FIG. 6 is a view showing a structure of a main part of a sixth embodiment of the heating and melting treatment apparatus according to the present invention, in which a slag port is provided at the bottom.

FIG. 7 is a system diagram showing a system configuration of Embodiment 7 of the heating and melting treatment apparatus according to the present invention in which a slag port is provided on a side wall.

FIG. 8 is a view showing a main structure of a heating and melting treatment apparatus according to an eighth embodiment of the present invention in which a slag port is provided on a side wall.

FIG. 9 is a view showing an example of the structure of a heating element used around the slag outlet of the present invention.

FIG. 10 is a view showing another example of the structure of the heating element used around the slag outlet of the present invention.

FIG. 11 is a view showing another example of the structure of the heating element used around the slag outlet of the present invention.

FIG. 12 is a diagram showing the degree of wear of a heating element according to the present invention in comparison with the degree of wear of a conventional graphite heating element.

FIG. 13 is a diagram showing a change in the amount of slag discharged continuously according to the present invention in comparison with a change in a conventional intermittent slag.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Electromagnetic induction heating furnace 2 Melting furnace coil 3 Furnace body refractory material 4 Graphite heating element 5 Melting slag 6 Cooling tube 7 Heating element 8 Face side heating element 9 Slag port 10 Self-coating layer 11 Supply port 12 Discharge port 14 Melting furnace High frequency power supply 15 High frequency power supply for slag port 16 Coil for slag port 17 Flow rate adjusting means 18 Temperature control device 20 Temperature measuring device for cooling pipe 21 Temperature measuring device for heating element 22 Cooling machine 23 Monitoring device 25 Graphite 26 SiC coating 27 Al ₂ O ₃ -Cr ₂ O ₃ -based refractory material 28 MoSi ₂ -based composite sintered body 30 DC power supply for slag port 31 Movable support 33 Electric resistance heating furnace 34 Graphite electrode 35 AC power supply 36 Cooling water for furnace body 37 Control device 43 Flow rate adjusting means for internal cooling 44 Flow rate adjusting means for low part cooling 45 Furnace internal cooling pipe 46 Furnace low part cooling pipe 47 Furnace internal refractory

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) B09B 3/00 F23G 5/00 115Z F23G 5/00 ZAB B09B 3/00 ZAB 115 303L (72) Inventor Ken Amano Ibaraki 7-1-1, Omikamachi, Hitachi City Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Osamu Ito 7-1-1, Omikamachi, Hitachi City, Hitachi City, Ibaraki Prefecture Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Koji Sato 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd.Hitachi Research Laboratory, Ltd. 72) Inventor Koichi Tatemura 3-1-1, Sachimachi, Hitachi City, Ibaraki Prefecture Inside Hitachi, Ltd.Hitachi Plant (72) Inventor Shige Kaneko 3-1-1, Sachimachi, Hitachi City, Ibaraki Prefecture Co., Ltd. F-term (reference) in Hitachi, Ltd. Hitachi Plant 3K061 AA23 AC03 CA11 DB19 NB01 NB28 4D004 AA36 CA29 CA32 CB31 CB43 DA01 DA02 DA06 DA12 DA20

Claims (14)

[Claims] 1. A heating and melting treatment apparatus for heating and melting a solid and / or powder, wherein a slag outlet from which a melt flows out is provided at the bottom of the melting furnace, and a non-conductive refractory is provided around the entrance of the slag opening. A heating and melting treatment apparatus, comprising: means for cooling the refractory material from inside; and a heating element around the outlet of the slag port. 2. A heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag outlet from which a melt flows out is provided at the bottom of the melting furnace, and a non-conductive refractory is provided around the entrance of the slag opening. A heating and melting treatment apparatus, comprising: means for cooling the refractory material from the inside; and a heating element and a non-conductive refractory material around the outlet of the slag port. 3. A heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag port through which a melt flows out is provided at the bottom of the melting furnace, and the vicinity of the entrance of the slag port is electrically non-conductive with a heating element. A heating and melting treatment apparatus comprising: means for cooling the refractory material from the inside; and a heating element around the outlet of the slag port. 4. The heat melting treatment apparatus according to claim 1, wherein an outlet hole of the slag port is wider than an inlet hole of the slag port. Processing equipment. 5. A heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag outlet from which a melt flows out is provided at the bottom of the melting furnace, and heat is generated around the entrance to the outlet of the slag outlet. A heating and melting treatment apparatus comprising: a body and a non-conductive refractory material; and means for cooling the refractory material from the inside. 6. A heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag port from which a melt flows out is provided at the bottom of the melting furnace, and the periphery of the slag port is a non-conductive refractory material. And a means for cooling the refractory material from the inside, and a heating element inserted and installed in the hole of the slag port. 7. A heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag outlet from which a melt flows out is provided at a bottom portion of the melting furnace, and a heating element constituting a periphery of the entrance of the slag outlet is provided. The heating element is disposed so as to protrude into the furnace, and the heating element side surface and the heating element upper surface which do not constitute the slag outlet are covered with a non-conductive refractory material. A heating and melting treatment apparatus, which is provided so as to extend so as to cover an upper surface of a mouth, and has means for cooling the non-conductive refractory material from the inside. 8. A heating and melting treatment apparatus for heating and melting a solid and / or powder, wherein a slag port through which a melt flows out is provided on a side wall of a melting furnace, and the periphery of the slag port is a non-conductive refractory material. A heating and melting treatment apparatus comprising: means for cooling the refractory material from the inside; and a heating element provided at a position facing the outlet of the slag port and away from the outlet. 9. A heating and melting treatment apparatus for heating and melting a solid and / or a powder, wherein a slag port through which a melt flows out is provided on a side wall of the melting furnace, and a lower side of the slag port is a non-conductive refractory. A heating and melting treatment apparatus comprising: means for cooling the refractory material from the inside; and a heating element provided above the slag port. 10. The heating and melting treatment apparatus according to claim 9, wherein a heating element is provided at a position facing the outlet of the slag port and away from the exit. 11. The heating and melting treatment apparatus according to claim 1, wherein the heating element is graphite coated with silicon carbide.
A heat-melting treatment apparatus characterized in that the heat-melt processing apparatus is any one of a conductive ceramic containing a metal boride, a conductive ceramic containing a metal silicide, a non-conductive refractory material containing the graphite or the conductive ceramic. . 12. The heating and melting treatment apparatus according to claim 1, wherein the refractory material surrounding the slag port is a ceramic containing zirconium boride or molybdenum silicide. A heating and melting treatment apparatus. 13. The heating and melting treatment apparatus according to claim 1, wherein the cooling unit is a unit that cools the refractory material with a refrigerant, and controls a flow rate of the refrigerant in the cooling unit. Means, a means for controlling the amount of heat generated by the heating element, a temperature measurement means installed inside the non-conductive refractory material, and a temperature measurement means installed inside or near the heating element, Means for controlling the flow rate of the refrigerant and the calorific value of the heating element based on the measured temperatures. 14. The heating and melting treatment apparatus according to claim 13, further comprising: a monitoring device for monitoring a status of an outlet of the slag port in a non-contact manner, based on a status of the slag port obtained by the monitoring device. A heating and melting treatment apparatus comprising means for controlling a flow rate of the refrigerant and a calorific value of the heating element.