JPH0355411A - Melting disposing device for incinerated ash - Google Patents

Abstract

PURPOSE:To prevent cooling of slug at a discharge port and to enable continuous outflow of the slug by a method wherein the irradiation region of a plasma arc contains the slug discharge port of a melting furnace by means of the inclining device of a plasma torch. CONSTITUTION:A drive device 1 actuates a hydraulic device by means of a command from a control device 26 to lower a plasma torch 8 to the interior of a plasma arc furnace 5 and the lowering distance is set to a given value based on a pair electrode 10. When discharge of the plasma torch 8 is completed and melting disposal of incinerated ash B is completed, the plasma torch is raised from a furnace cover 7. Since the plasma torch 8 is formed such that it is rotatable in the direction of an arrow mark Q centring around a fulcrum 35 throughout a range of an inclination angle theta by means of an inclining device 2, a plasma irradiation region is varied. The irradiation region is set to a range of from a wall surface on the ash charge side of molten slug 13 to the tip of a slug discharge port 25. The single plasma torch 8 effects operation to melt the incinerated ash B and operation to heat the slug discharge port 25 of a furnace body 6, molten slug is prevented from being cured at the sludge discharge port 25, and slug can be continuously discharged.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an incineration ash production method in which incineration ash generated by incinerating municipal waste, sewage sludge, or other waste in an incinerator is melted in a melting furnace. Regarding melt processing equipment. [Prior Art] In general, incineration ash generated by incinerating municipal waste, sewage sludge, or other waste in waste incinerators is currently disposed of in landfills in many cases. However, as it becomes increasingly difficult to secure landfill sites year by year, there is a need for a method to reduce the volume of incinerated ash to be landfilled, that is, a volume reduction process. In addition, if incinerated ash is disposed of in a landfill without being treated, the incinerated ash itself contains harmful substances such as various heavy metals, and the harmful substances are released from the incineration into rainwater. Leaching into groundwater, etc.
Alternatively, unburned organic substances in the incineration ash decompose, and these phenomena cause secondary pollution. Therefore,
There is a demand for pollution-free treatment of incineration ash discharged from incinerators. For this reason, various incineration ash processing devices have been developed. For example, a treatment method that mixes incinerated ash with cement and solidifies it with cement, a treatment method that solidifies incinerated ash by mixing it with asphalt, or a treatment method that sinters and solidifies incinerated ash by mixing it with clay etc. is disclosed. However, these processing methods have the problem of high processing costs and lack of technical reliability regarding falsification of the processing status of incinerated ash. Another method for processing incinerated ash is to put the incinerated ash into a burner furnace or an electric furnace (oven arc furnace) and melt the incinerated ash.The burner furnace method utilizes the combustion heat of oil. This method has a maximum temperature of about 1400℃, and it is necessary to remove high melting point iron and iron particles in the preliminary stage. Alternatively, the arc furnace method is a repurposed steelmaking arc furnace for pressure melting, and utilizes arc heat between graphite electrodes. For example, as a treatment method using an open arc furnace for steel manufacturing, there is a method disclosed in JP-A-52-86976. The sludge combustion melting method involves charging the sludge into a closed arc furnace in which an arc is constantly generated between an electrode and molten metal, and the organic matter in this sludge is decomposed by the heat of the arc and converted into gas. The slag is taken out of the furnace, and the inorganic substances in the slag are melted by the arc heat of the arc and melted into the molten metal, or taken out of the furnace as molten slag.

Alternatively, Japanese Patent Laid-Open Publication No. 114383/1983 discloses a method for melting incineration ash. The method for melting incinerated ash involves sequentially introducing incinerated ash onto molten slag in a submerged arc furnace to form an incinerated ash layer, and sequentially melting the incinerated ash in this layer using the electrical resistance heat of the molten slag. It is. In this case, the incinerated ash is a mixture of ash emitted by incineration in an incinerator and collected ash collected in a dust collector. [Problems to be Solved by the Invention] However, most of the burner furnace systems described above use a water crushing method to remove the slag because a high temperature cannot be obtained. The water crushing method is a water tank installed at the bottom of the slag discharge port, and the slag is continuously dropped from the discharge port into the water tank.
This is a method in which slag that has been cooled in a water tank is taken out of the melting furnace using a conveyor, etc. It has the advantage that the outside air is sealed with water so that the cold air that leaks into the slag discharge port does not cool the slag. This has become a problem as it has become a glass award, and there are problems in terms of the effective use of the granulated slag. In addition, the method of burning and melting surasoji disclosed in the above-mentioned Japanese Patent Application Laid-open No. 52-86976 uses an oven arc furnace using graphite electrodes, so it is not possible to obtain a sufficiently high temperature. In particular, there is a problem that it is not possible to completely melt the high melting point substances contained in municipal waste incineration ash, such as earth and sand, ceramics, metals, etc. Therefore, only the substances that can be melted in the oven arc furnace are used. In order to feed the ash into an arc furnace, it is necessary to sort out high-melting point substances from the incinerator in advance and then feed them into the furnace, or add melting point depressants such as lime or fluorspar to the incinerated ash and melt it. there were.

In addition, in an oven arc furnace, an arc is generated between the t-electrode and the molten metal, so it is necessary to treat waste such as incineration ash, which is mainly composed of oxides contained as slag components. In this case, it is necessary to melt metals such as iron in a furnace in advance to prepare the so-called base metal. Furthermore,
When incineration ash with a non-uniform composition of oxides etc. was placed on the base metal, the arc power fluctuated greatly and the arc disappeared. Moreover, if the arc is extinguished, the base metal will be covered with non-conductive incinerated ash, so the incinerated ash will have to be disposed of again, making it impossible to re-ignite the incinerated ash. occurred often.

Methods other than the water crushing method include the wind crushing method and the slow cooling method, but the slag produced by these methods is crystalline and hard, so it can be effectively used as construction aggregate, road base material, etc. . A common slag discharge method such as this slow cooling method is the tap method used in iron manufacturing such as blast furnaces. The tap method is to store slag in the melting furnace by filling the slag discharge port with clay to prevent the slag from flowing out, and when a predetermined amount of slag has accumulated, the clay at the slag discharge port is broken down and the slag is removed. The slag is discharged from the discharge port, and after the slag has finished flowing out, the discharge port is filled with clay again.The slag discharge operation is intermittent, and as the slag remains in the furnace, the volume of the furnace increases. , problems arise in work safety. In addition, when discharging slag using a slow cooling method other than the tap method, for example, by continuous slag, the temperature at the slag outlet decreases, causing the problem that the slag cools and solidifies at the outlet and does not flow out. Especially in melting furnaces,
When melting incinerated ash without separating iron and ceramics, the melting point of the incinerated ash is as high as 1,500°C or higher, so even a slight temperature drop causes the problem that slag easily cools and solidifies at the discharge port. There is. That is, once the slag solidifies at the discharge port of the melting furnace, it gradually becomes thicker and the discharge port becomes clogged, forcing the operation of the melting furnace to be stopped. When incineration ash is melted using an arc furnace and the slag is discharged using a method other than a tap, it is common to install an auxiliary electrode or an auxiliary burner at the slag discharge port. However, auxiliary electrodes and auxiliary burners require oversized equipment, and the energy used for melting cannot be used effectively, resulting in wasted energy. In addition, burner furnaces cannot achieve higher temperatures than open arc furnaces,
Moreover, since a large amount of air is used for combustion of fuel, the amount of exhaust gas is enormous, resulting in various problems such as the need for large-scale wandering gas processing equipment. In general, plasma is a state in which electrons are ejected from atoms and ionized.The high energy generated when electrons eject from atoms creates a high-temperature atmosphere near the plasma. A plasma arc furnace is provided to generate this plasma. This plasma arc furnace is equipped with a plasma torch. In addition, the incinerated ash and combustion exhaust gas generated from the incinerator are cleaned with a precipitator such as an electrostatic precipitator, and the collected dust is processed in a melting furnace. It passes through the chimney and is discharged from the chimney. The purpose of this invention is to solve the various problems mentioned above, and to reduce the volume of incinerated ash from incinerators for municipal waste, industrial waste, etc., make it harmless, and use it effectively by melting it. However, when melting incineration ash without separating iron and ceramics, a high temperature of 1,500°C or higher is required, but with plasma arc, we focused on the fact that high temperatures of 1,500 to 2,000°C can be easily obtained. Regardless of the type and size of the incinerated ash, for example, even if the incinerated ash contains high melting point substances such as metals, IIIiJ containers, earth and sand, these high melting point substances cannot be removed from the incinerated ash in advance. , the incinerated ash is directly put into the melting furnace, a plasma arc is generated using a plasma torch, which is a plasma generator installed in the melting furnace, and the incinerated ash is melted by the high energy of the plasma, making it stable at all times. In addition to disposing of incineration waste, when air-pulverized slag or slow-cooled slag is continuously discharged from an incinerator, the slag cools and solidifies at the slag discharge port, blocking the sprue, preventing the slag from flowing out, and causing melting. In order to solve the problem of having to stop the furnace, the plasma torch was tilted around a fulcrum so that the area that could be irradiated with the plasma arc was from the molten slag surface in the furnace to the tip of the slag discharge port. The purpose of the present invention is to provide an incineration ash melting treatment device that directly heats the slag at the discharge port with a plasma arc, prevents the slag from cooling, allows continuous flow, and solves the problem without using excessive energy. [Means for Solving the Problems] In order to achieve the above object, the present invention is constructed as follows. That is, the present invention includes a plasma torch disposed in a melting furnace that generates a plasma arc, a drive device that moves and adjusts the plasma torch in the axial direction, and changes the irradiation direction of the plasma torch! 3. Tilt to adjust the tilt of the plasma torch! A melting process for incinerated ash, wherein the direction of the plasma torch can be changed so that the irradiation area of the plasma arc from the plasma torch includes the slag discharge port of the melting furnace by driving the tilting device. Regarding the equipment. In addition, in this re-installation of the incineration ash melting process, the plasma torch is placed above the slag discharge port of the melting furnace. Furthermore, in the re-installation of the incineration ash melting process, the exhaust gas outlet of the exhaust gas is opened at the lower part of the slag discharge port. , is constructed as described above and has the following effects. That is, this incineration ash melting processing apparatus has a U.S. which adjusts the movement of a plasma torch, which is placed in a melting furnace and generates a plasma arc, in the axial direction. and a tilting device that changes and adjusts the angle of the plasma torch in order to change the irradiation direction of the plasma arc, so that by driving the #lk tilting position VT, the irradiation direction of the plasma arc from the plasma torch is The direction of the plasma torch may be changed to include the slag outlet of the melting furnace, and the molten slag may be prevented from cooling and solidifying at the slag outlet of the melting furnace.
Molten slag can be continuously discharged from the slag discharge port. In addition, in this incineration ash melting processing apparatus, the plasma torch is arranged above the slag discharge port, and the plasma torch is tilted by a tilting device, so that the irradiation area of the plasma arc is from the ash input side wall surface of the slag bath to the slag discharge port. Since the plasma torch is not located directly above the molten slag but is located at the edge of the melting furnace, the influence of radiant heat of the molten slag is reduced.Furthermore, the slag discharge port is Since the slag is located below the slag, the high-temperature exhaust gas is constantly in contact with the slag discharge port, so that the floating slag can be maintained at a high temperature and can be prevented from being cooled and solidified at the slag discharge port.

〔Example〕

Hereinafter, an embodiment of the incineration ash melting processing apparatus according to the present invention will be described with reference to the drawings. In Figure 1,
An example of this incineration ash melting processing equipment is shown. This incineration ash melting treatment equipment is used to collect incineration ash generated by incinerating municipal waste, sewage sludge, or other waste in an incinerator, and in some cases, 11i, which is collected by a dust collector in an incinerator system. The mixed dust is mixed and melted in a melting furnace, that is, a plasma arc furnace 5,
Mainly, the plasma arc furnace 5, the plasma arc furnace 5
The plasma torch 8 is provided with a plasma torch 8, and a plasma system 1 that causes the plasma torch 8 to generate plasma. As shown in FIG. 1, this plasma system 1 mainly consists of a plasma arc torch 8, a power supply that switches alternating current to direct current and supplies direct current to plasma torch 8! J24, a control rn device 26 that generates a plasma arc by the plasma torch 8 and performs control to stably supply the plasma arc, a cooling water supply device 127 that supplies cooling water for cooling the electrode and the torch body, and It has an air supply device 28 for supplying air A in the form of plasma or gas.

As shown in FIG. 2, on one side of the furnace lid 7 of the plasma arc furnace 5, there is an ash hopper l2 into which incinerated ash generated from the incinerator or dust B collected from the dust collector is charged. The plasma arc furnace 5 is continuously or intermittently supplied from the ash hopper 12 through the chute 9 by the ash supply device W3.
will be put into the

The plasma arc furnace 5 is provided with a water-cooled fixed type furnace M7 on the upper part of the furnace body 6. The furnace body 6 is constructed of a refractory material such as carbon, magnesia, or alumina.
Further, a plasma torch 8 is provided on the other side of the furnace lid 7 of the plasma arc furnace 5.
A slag discharge port 25 is formed in the furnace body 6 below. This slag discharge port 25 communicates with a slag receiving container l5 located below and an exhaust gas duct 23 extending upward. Furthermore, the plasma torch 8 is equipped with a torch lifting device, that is, a driving device 1, which moves the plasma torch 8 in the axial direction.
1 is installed in the furnace M7 so that the plasma torch 8 can be set at a predetermined position within the furnace body 6. Further, the plasma torch 8 includes a plasma torch 8 in order to change the irradiation direction of the plasma torch 8.
A tilting device 2 is provided to change the inclination of the. By driving this tilting device 2, the direction of the plasma torch 8 can be changed. The area irradiated with plasma from the plasma torch 8 can be set to include the slag discharge port 25 of the plasma arc furnace 5. The plasma arc furnace 5 in the incineration ash melting processing apparatus according to the present invention is controlled as described above, and operates as follows. In this plasma arc furnace 5, the plasma torch 8 operates the drive device 11 to change the distance of the plasma torch 8 from the incinerated ash B according to a predetermined voltage or power bottle of the plasma torch 8. That is, the drive device 11 moves the plasma torch 8 up and down in the axial direction, that is, in the direction of the arrow R, and is moved horizontally from a double-acting cylinder, for example. This drive device l is a control device 2
The hydraulic system is activated by the command from 6 to move the plasma torch 8 in the direction of the cough axis so that it can rise and fall relative to the furnace M7. For example, when the plasma torch 8 is lowered into the plasma arc furnace 5, the plasma torch 8 is set at a predetermined distance from the counter electrode IO, and the discharge of the plasma torch 8 is completed and the melting process of the incinerated ash B is completed. , the furnace again by the drive 11! Increase from 17. In addition, plasma torch 8
is configured to be able to swing or tilt over a tilting angle θ by a tilting device 2. This tilting device 2 is configured to be able to rotate or pivot in the direction of arrow Q about a pivot point 35 by means of a polege 3 int or the like, so that the plasma torch 8 can be rotated or tilted over a tilting angle θ. I come to do it. Therefore, this tilting device 2 is operated in response to a command from the control device 26, and the plasma torch 8 is rotated by the tilting device 2, thereby changing the plasma irradiation area. This plasma irradiation IJIM consists of a slag bath, that is, a molten slag 1
The distance from the ash input side wall surface of No. 3 to the tip of the slag discharge port 25 is set. In this case, the plasma torch 8 and the drive device 11 fixing the plasma torch 8 are configured to be tilted together. Therefore, one plasma torch 8 melts the incinerated ash B and heats the slag discharge port 25 of the furnace body 6, preventing the molten slag from solidifying at the slag outlet 25 and continuously removing the slag. It is something that can be discharged. The molten slag flowing out from the slag discharge port 25 is stored in a slag receiving container l.
5 is accepted and discharged, but slag acceptance! Slag discharge port 2 is caused by air leaking from the gap between S15 and furnace body 6.
Once 5 has cooled, the plasma torch 8 must be frequently tilted towards the slag outlet 25. The exhaust gas outlet 16 is connected to the slag receiving container 15 below the slag discharge port 25.
By installing the slag discharge port 25 in a place close to the plasma torch 8 and sucking the exhaust gas and leaked air into the exhaust gas outlet 16, cooling of the slag discharge port 25 is prevented, and the time for heating the slag discharge port 25 with the plasma torch 8 is shortened. If most of the plasma energy of 8 is used for melting the incinerated ash B, this plasma arc furnace 5 can provide an energy-saving device. The part where the incinerated ash B is supplied by the ash supply device 3 is the part where the incinerated ash B is supplied.
The required amount of heat is large because it supplies the amount of heat to heat the ash to its melting temperature and the heat of fusion of the incinerated ash B. On the other hand, for the slag discharge port 25, it is sufficient to apply an amount of heat to the extent that the molten slag does not cool down, and the required amount of heat is small. In addition, the slag depth in the slag bath l3 portion is 200 u or more, whereas the slag depth in the slag discharge port 25 portion is 50 m.
If the amount of heat obtained from the plasma torch is too large, there is a risk that the refractory material forming the slag discharge port 25 will be burnt out. As shown in FIG. 2, the ash supply device 3 and the slag discharge port 25
If the plasma arc furnace 5 and the plasma arc furnace 5 are placed opposite each other, and the plasma torch 8 is placed directly above the slag discharge port 25, the distance between the slag discharge port 25 and the tip of the plasma torch 8 is the shortest, and the distance between the slag discharge port 25 and the tip of the plasma torch 8 is the shortest, and the The distance between the surface of the slag bath 13 near the wall and the tip of the plasma torch 8 is always the longest. As a result, the minimum amount of heat can always be given to the slag discharge port 25, and the maximum amount of heat can be given to the slag bath 13 at the lower part of the ash offering lining 3, so that the thermal energy of the plasma can be adjusted appropriately. Furthermore, if the plasma torch 8 is placed above the center of the slag bath 13, there is a high risk that the plasma torch 8 itself will receive the radiant heat from the slag bath 13, causing the plasma torch 8 to burn out. By arranging the plasma torch 8 above the slag discharge port 25, the plasma torch 8 can be prevented from burning out and the life of the plasma torch 8 can be extended.

Furthermore, the plasma torch 8 used in this plasma incineration ash melting device has two types of arc discharge: a transfer type as shown in Fig. 3, and a non-transfer type as shown in Fig. 4. These are the ones that can be used. The transfer type requires a negative counter electrode, and the non-transfer type uses the tip of the plasma torch as the counter electrode, so it does not require a negative counter electrode other than the plasma torch. In addition, the thermal efficiency of the plasma torch 8 body is 92 to 94% for the transfer type and 85% for the non-transfer type, and the transfer type is superior in terms of thermal efficiency, while the non-transfer type does not require a counter electrode in terms of ease of handling. is excellent.

For example, as shown in the figure, the plasma torch 8 is connected to the sprue section 25.
When a transfer type arc discharge type is used, the counter electrode 10 of the plasma torch 8 is embedded in the bottom of the furnace body 6. A plasma arc is generated between an electrode (+ electrode) housed in the plasma torch 8 and a counter electrode 10 (single pole) provided at the bottom of the furnace body 6.

Ten poles from the IT source supply device 4 are connected to the plasma torch 8 through a cable 17, and one pole is connected to a counter electrode 10, which is a graphite electrode, through a cable 22. A predetermined voltage is applied in between. Since the molten slag 13 is conductive, when the molten slag 13 is present in the furnace, the entire surface of the slag bath becomes the counter electrode 10. In addition, in the case of the non-transfer type, a counter electrode of the graphite electrode is not required, and one pole is connected to the electrode built in the plasma torch 8 through the cable 18. In order to generate plasma in the plasma torch 8,
The precepts are attained by the functions of plasma system 1. When the plasma torch 8 is a transfer type, the distance between the tip of the plasma torch 8 and the counter electrode 10 is proportional to the voltage of the plasma torch 8, and as the distance increases, for example, about 10.5
The voltage increases at a rate of V/am. Since the electric mass of the plasma torch 8 is controlled at a constant level by commands from the control device 26, the power position is proportional to the distance, and the longer the distance, the more power consumption increases, and the heat agitation given to the material to be melted, that is, the incinerated ash B, is reduced. To increase. At this time, the current is PTDi! In the case of a transfer type plasma torch, the voltage is determined only by the distance between the counter electrodes and the fluctuation cycle of the arc gas pressure.

In the case of a non-transfer type plasma torch, it is determined by the fluctuation cycle of the arc gas pressure. When using a transfer type plasma torch 8, the incinerated ash B is melted by generating a plasma arc between the ten poles built into the plasma torch 8 and the slag bath, which is one pole. . In addition, when using a non-transfer type plasma torch, a plasma arc is generated between ten poles and one pole built into the plasma torch, and the incinerated ash B is evaporated by the arc heat, that is, the plasma energy. Melt it. Furthermore, the cooling water pump 29 in the cooling water supply device 27 is operated to send the cooling water from the water tank 30 to the heat exchanger 33, and after exchanging heat in the cough heat exchanger 33, the heat exchange! Water is supplied from @33 to the manifold 34 and then to the plasma torch 8 through the cooling water pipes 19 and 20 to cool the plasma torch 8. In addition, the air compressor of the air supply device 28 is operated,
Compressed air is supplied from the manifold 34 to the plasmas 1-8 through the plasma-shaped air pipes 21.

In the incineration ash melting device according to the present invention, 1'N! from the incineration ash B generated from the incinerator or the dust collector! The collected dust B is put into the ash hopper 12, and the incinerated ash B is continuously or intermittently transferred to the plasma arc furnace 5 through the chute 9.
will be put into the Furthermore, in order to generate a plasma arc, a high energy pulse is applied between the electrodes built into the plasma torch 8 under predetermined setting conditions for discharging the plasma arc to generate a pilot arc. Then, after the main arc is generated, a predetermined current (e.g. 200~300A) and a predetermined voltage (e.g. 400~300A) are applied.
500V), the thermal energy of the plasma arc can be applied to the incinerated ash 13, which is the object to be heated.
When the plasma torch 8 is a transfer type, the distance between the tip of the plasma torch 8 and the counter electrode 10, which is a graphite electrode, must be in the range of 251i to 754 in order to generate a main arc. After the main arc is generated, the tip of the plasma torch 8 and the counter electrode 10 are electrically connected by the plasma flow, so the drive device l1 is activated to raise the plasma torch 8 and increase the output. Even if the distance is 75 degrees or more, the plasma will not be interrupted. Since the slag bath or molten slag 13 also serves as the counter electrode 10 of the plasma torch 8, it needs to have a certain depth. If the molten slag 13 is too shallow, the incinerated ash B will not be melted and will pile up on the surface of the slag bath, resulting in loss of conductivity and causing interruption of the plasma arc. Also,
On the other hand, if it is too deep, the lower part of the molten slag 13 will solidify. Therefore, the depth of the molten slag 13 is l
The range is preferably from 00 to 400 n.

Therefore, a plasma arc is generated by the discharge of the plasma torch 8, and the thermal energy of the plasma arc is given to the incinerated ash B containing oxides, highly molten substances, etc. by radiation or conduction, and the incinerated ash B is transferred to the slag bath. The metal is heated and melted by the plasma arc generated by the plasma torch 8 to become molten slag, that is, the molten slag 13, and the metal is continuously or intermittently flowed out from the sprue 25 of the furnace body 6 as molten metal to form the slag S. The slag is taken out to the outside as a slag yard 14. The molten slag S that flows out is transferred to the slag receiving container 15.
When the slag receiving container 15 becomes full of slag S, the slag S is discharged out of the furnace by replacing it with another slag receiving container 15. Furthermore, combustion gas C generated by melting the incinerated ash B is sent from the exhaust gas outlet 16 through the exhaust gas duct 23 to an exhaust gas treatment device (not shown), and then is sucked and discharged from the exhaust gas treatment device by an induction fan. be done.

〔Effect of the invention〕

The incineration melting treatment apparatus according to the present invention is constructed as described above, and has the following effects. That is, this incineration ash melting processing apparatus includes a plasma torch disposed in a melting furnace that generates a plasma arc, a drive device that moves and adjusts the plasma torch in the axial direction, and a drive device that changes the irradiation direction of the plasma torch. A IIJI moving device for changing and adjusting the tilt of the plasma torch, and driving the tilting device to change the direction of the plasma torch so that the irradiation area of the plasma arc from the plasma torch includes the slag discharge port of the melting furnace. Since the slag can be changed, the plasma torch is moved around 1 and the slag discharge port is heated with plasma, thereby continuously converting the molten slag into the slag without using extra energy such as an auxiliary burner. It can be discharged smoothly through the discharge port. Since the molten slag can be continuously discharged, there is no need for the slag to stay in the furnace for a long time as in a tap-type melting furnace, so the volume of the furnace body can be configured to be small, and it is economically possible to reduce the plasma production at low cost. It is possible to provide an arc furnace, and by sequentially directly introducing incinerated ash containing high-melting point substances discharged from the incinerator into the melting furnace, and supplying air as a plasma-type gas to the plasma torch installed in the melting furnace. The incinerated ash can be rapidly melted by generating a plasma arc and applying the thermal energy of the plasma arc to the incinerated ash by radiation or conduction. Furthermore, since a plasma arc is used instead of a conventional ordinary arc, a continuously stable high temperature can be obtained, and since there is almost no fluctuation in power, there is little effect on the t-source.

Further, in this incineration ash melting processing apparatus, since the plasma torch is disposed above the slag discharge port, cooling of the sprue by cold air entering through the gap between the slag discharge port and the slag receiving container can be suppressed, resulting in energy savings. Even if the slag is cooled with cold air, it can be heated with a plasma arc and flowed out, so there is no need to completely seal the slag outlet with a water seal, so slowly cooled slag with greater hardness than granulated slag can be obtained. This expands the scope of effective use of slag. Further, the ash supply device and the slag outlet can be arranged at opposite edges of the plasma arc furnace, and by arranging the plasma torch directly above the slag outlet, the slag outlet can be gives the least amount of heat,
The energy distribution can also be adjusted appropriately to give the maximum amount of heat to the ash supply port. Moreover, by arranging the plasma torch directly above the slag discharge port, the radiant heat that the plasma torch receives from the slag bath is smaller than when the plasma torch is arranged above the slag bath. Burnout can be prevented. Furthermore, by installing the exhaust gas outlet at the lower part of the slag outlet, the slag outlet can be effectively heated by the radiant heat of the high-temperature exhaust gas, and the phenomenon of cooling and solidifying the molten slag at the slag outlet can be prevented. ．．

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an example of the incineration ash melting processing apparatus according to the present invention, and FIG. 2 is a sectional view showing an embodiment of the plasma arc furnace of the incineration ash melting processing apparatus according to the present invention.
Fig. 3 is an explanatory diagram for explaining the transfer type plasma torch used in the plasma arc furnace shown in Fig. 2, and Fig.
It is an explanatory diagram illustrating non-transfer type plasma 1--chi used in the plasma arc furnace shown in the figure. 1... Plasma arc furnace (melting furnace), 6...
- Furnace body, 7 Furnace lid, 8 Plasma torch, 10 Counter electrode, 11...
Drive device, l3.1.1 molten slag, 25... slag discharge port, B... incineration ash.

Claims (3)

[Claims] (1) A plasma torch disposed in a melting furnace that generates a plasma arc, a drive device that moves and adjusts the plasma torch in the axial direction, and changes and adjusts the inclination of the plasma torch to change the irradiation direction of the plasma torch. Incineration ash melting processing comprising a tilting device configured to change the direction of the plasma torch so that the irradiation area of the plasma arc from the plasma torch includes the slag discharge port of the melting furnace by driving the tilting device. Device. (2) The apparatus for melting incinerated ash according to claim 1, wherein the plasma torch is arranged above the slag discharge port of the melting furnace. (3) The apparatus for melting incinerated ash according to claim 1 or 2, wherein the exhaust gas outlet of the exhaust gas is located below the slag outlet.