JPH0730893B2 - Incinerator ash melting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to incineration ash for melting and treating incinerator ash generated by incinerating municipal solid waste, sewage sludge, or other waste in an incinerator. Of the melting treatment device of

[Conventional technology]

In general, incinerator ash generated by incinerating municipal solid waste, sewage sludge, or other wastes in a waste incinerator is currently landfilled in most cases.
However, since it is becoming more difficult to secure landfill sites every year, there is a demand for a method of reducing the volume of incinerated ash to be landfilled, that is, a volume reduction process for incinerated ash.

If the incinerated ash itself is landfilled in a landfill without being treated, the incinerated ash itself contains harmful substances such as various heavy metals. And the like, or the unburned organic substances in the incinerated ash are decomposed, and these phenomena cause secondary pollution. Therefore, there is a demand for pollution-free treatment of incineration ash discharged from the incinerator.

For this reason, various types of incineration ash treatment devices have been conventionally developed. For example, a treatment method in which incineration ash is mixed with cement to solidify the incineration ash with cement, a treatment method to mix incineration ash with asphalt to solidify the incineration ash, or a treatment method to mix incineration ash with clay or the like to sinter and solidify the incineration ash. Is disclosed.

However, these treatment methods have a problem that the treatment cost becomes high and the technical reliability of the treatment state of the incineration ash is lacking.

Further, as another treatment method of incineration ash, there is a method in which the incineration ash is put into a burner furnace or an electric furnace, that is, an open arc furnace, and the incineration ash is melted. The burner furnace method uses the combustion heat of oil and has a maximum temperature of about 1400 ° C.
High melting point iron and ceramics need to be removed in the previous step. Alternatively, the arc furnace system is an arc furnace for steelmaking which is diverted for pressure melting, and utilizes arc heat between graphite electrodes.

For example, as a processing method using an open arc furnace for steelmaking, there is one disclosed in Japanese Patent Laid-Open No. 52-86976.

The combustion and melting method of the sludge, the sludge is charged into a closed arc furnace in which an arc is constantly generated between the electrode and the molten metal, and the organic matter in the sludge is decomposed by the arc heat of the arc as a gas. The inorganic substance in the sludge is taken out of the furnace and is melted by the arc heat of the arc to be melted in the molten metal or taken out of the furnace as molten slag.

Alternatively, JP-A-55-114383 discloses a method for melting incinerated ash. The melting treatment method of the incineration ash is one in which the incineration ash is sequentially charged onto the molten slag in the submerged arc furnace to form an incineration ash layer, and the incineration ash of the layer is sequentially melted by electric resistance heat of the molten slag. Is. In this case, as the incineration ash, a mixed ash of ash that is incinerated and discharged by incineration ash and dust ash that is collected by the dust collector is used.

[Problems to be Solved by the Invention]

However, most of the above burner furnace systems use a water granulation system as a method for taking out slag because a high temperature cannot be obtained. With the water granulation method, a water tank is installed under the slag discharge port, and the slag is continuously dropped from the discharge port into the water tank.
A method of taking out the slag cooled in the water tank to the outside of the melting furnace with a conveyor, etc., but by sealing the outside air with water, there is an advantage that the cold air that has leaked into the slag discharge outlet will not cool, but on the other hand, granulated slag Is glassy and becomes brittle, which is problematic in that the granulated slag is effectively used.

Further, since the sludge combustion and melting method disclosed in Japanese Patent Laid-Open No. 52-86976 uses an open arc furnace using a graphite electrode, a sufficient high temperature cannot be obtained, and therefore the incineration ash is not obtained. Especially, in the case of municipal waste incineration ash, there is a problem that the high melting point substances such as earth and sand, pottery and metal contained in the ash cannot be completely melted. Therefore, in order to put only the substance that can be melted in the open arc furnace into the open arc furnace, after selecting the high melting point substance from the incinerator in advance, it is put into the furnace or the melting point of lime, fluorite, etc. It was necessary to add a depressant to the incineration ash for melt processing.

Further, in the open arc furnace, in order to generate an arc between the electrode and the molten metal, in order to treat waste such as incinerated ash, which is mainly composed of an oxide contained as a slag component, It is necessary to melt a metal such as iron in a furnace in advance to form a so-called base metal. Furthermore,
When the incinerated ash having a non-uniform composition such as oxide was put on the base metal, the arc power fluctuated greatly and the arc extinguished. Moreover, when the arc is extinguished, the incinerated ash that has no electrical conductivity is covered on the base metal, and the incinerated ash is processed again.Therefore, there is often a problem that the incinerated ash cannot be re-ignited. occured.

Other than the water granulation method, there are a wind granulation method and a slow cooling method, but the slag produced by these methods is crystalline and hard, so it has the property that it can be effectively used for construction aggregates and roadbed materials. . A general slag discharging method such as the slow cooling method is a tap method used for steelmaking such as blast furnace.

With the tap method, clay is packed in the slag discharge port so that the slag does not flow out, and the slag is stored in the melting furnace.
When the amount of slag accumulated is a predetermined amount, the clay in the slag discharge port is crushed to allow the slag to flow out from the discharge port, and after the slag has finished flowing out, the discharge port is filled with clay again. Since it is intermittent and the slag is retained in the furnace, the capacity of the furnace becomes large, which causes a problem in work safety.

In addition to the tap method, discharging slag of a slow cooling method by continuous slag, for example, causes a problem that the slag is cooled and solidified at the discharge port and does not flow out because the temperature of the slag discharge port is lowered.

Especially when melting incineration ash that does not separate and remove iron and ceramics in a melting furnace, the melting point of the incineration ash is 1500 ° C.
Since it becomes higher than the above, there is a problem that the slag is easily cooled and solidified at the discharge port even if the temperature is slightly decreased. That is, once the slag is solidified at the discharge port of the melting furnace, it gradually grows, the discharge port is blocked, and the operation of the melting furnace must be stopped.

When incinerating ash is melted using an arc furnace and an slag is discharged by a method other than tapping, it is common to install an auxiliary electrode or an auxiliary burner at the slag discharge port. However, the auxiliary electrode and the auxiliary burner are excessively large in equipment, and the energy used for melting cannot be effectively used, resulting in a waste of energy. Moreover, in the case of a burner furnace, a higher temperature than that of an open arc furnace cannot be obtained,
Moreover, since a large amount of fuel combustion air is used, the amount of exhaust gas becomes enormous, resulting in various problems such as the need for a large-scale exhaust gas treatment device.

Generally, plasma is a state in which electrons are ejected from atoms to be ionized, which is high energy generated when electrons are ejected from atoms, and the vicinity of plasma is a high temperature atmosphere. Plasma arc furnaces have been provided to generate this plasma. A plasma torch is provided in this plasma arc furnace. In addition, the incineration ash generated from the incinerator and the combustion exhaust gas are cleaned with a dust collector such as an electric dust collector, and the collected dust is processed in the melting furnace. Pass through and exhaust from the chimney.

The melting processing equipment equipped with a plasma torch, which is a plasma generator that generates a plasma arc in the melting furnace, reduces the volume and detoxifies the incinerator ash of municipal waste, industrial waste, etc.
It can be melt-processed for effective use, and when incinerating ash is melted without separating iron and ceramics, 15
A high temperature of 00 ° C or higher is required, but in the plasma arc,
A high temperature of 1500 ° C to 2000 ° C can be easily obtained. Then, regardless of the type and composition of the incineration ash, for example, metal, pottery, even if the high melting point substances such as earth and sand are contained in the incineration ash, without removing those high melting point substances from the incineration ash in advance, The incinerated ash can be treated by directly charging the incinerated ash into the melting furnace and melting the incinerator ash by the high energy of the plasma provided in the melting furnace.

Therefore, an object of the present invention is to solve the above problems, a plasma torch is provided in a melting furnace for melting the incineration ash, the incinerator ash is directly charged into the melting furnace, and a plasma torch is used. When the incineration ash is always stably melted by the high energy of the plasma and the air-blown slag and the slowly cooled slag are continuously discharged, the molten slag is cooled and solidified at the slag discharge port to block the gate. In order to prevent the molten slag from flowing out, the plasma torch can be tilted around the fulcrum so that the area where the plasma arc can be irradiated is from the molten slag surface in the furnace to the tip of the slag discharge port. , The molten slag at the slag discharge port is directly heated by the plasma arc to prevent the cooling and solidification of the molten slag and to make it continuously flow out, in particular not to consume excess energy. Therefore, by effectively utilizing the thermal energy of the molten slag discharged from the slag discharge port and the exhaust gas, the molten slag at the slag discharge port is prevented from being cooled and solidified, and an incinerator ash melting treatment device that continuously discharges the molten slag is provided. Is to provide.

[Means for Solving the Problems]

The present invention is configured as follows to achieve the above object. That is, according to the present invention, a plasma torch for generating a plasma arc provided in a melting furnace, a slag discharge port for discharging molten slag provided on a side wall of a furnace body of the melting furnace, and a drop discharge from the slag discharge port. A slag receiving container arranged below the slag discharge port for receiving molten slag, an exhaust gas duct for opening an exhaust gas outlet of the exhaust gas between the slag discharge port and the slag receiving container in the lower part of the slag discharge port, and A drive device for moving and adjusting the plasma torch in the axial direction of the plasma torch, and an irradiation area of the plasma torch is changed by changing the irradiation direction of the plasma arc in the melting furnace so that the melting slag surface and the slag in the furnace body. And a tilting device for changing and adjusting the direction of the plasma torch so as to include the entire area of the discharge port. That relates to melt processing apparatus of incineration ash.

Further, in this incineration ash melting treatment apparatus, the plasma torch is arranged above the slag discharge port of the melting furnace.

[Action]

The apparatus for melting incinerated ash according to the present invention is configured as described above and has the following actions. That is, this melting apparatus for incineration ash comprises a driving device arranged in a melting furnace for moving and adjusting a plasma torch for generating a plasma arc, and a tilt of the plasma torch for changing the irradiation direction of the plasma arc. Since it has a tilting device for changing and adjusting, it is possible to change the direction of the plasma torch so that the irradiation range of the plasma arc from the plasma torch includes the slag discharge port of the melting furnace by driving the tilting device, A phenomenon in which the molten slag is cooled and solidified at the slag discharge port of the melting furnace can be prevented, and the molten slag can be continuously discharged from the slag discharge port.

In particular, the slag receiving container is arranged below the slag discharge port to receive the molten slag that is dropped and discharged from the slag discharge port, and the exhaust gas duct opens the exhaust gas outlet of the exhaust gas to the lower part of the slag discharge port. Therefore, the high-temperature exhaust slag and the high-temperature exhaust gas stored in the slag receiving container always give radiant heat, that is, thermal energy to the slag discharge port, so that the slag discharge port can be maintained at a high temperature, and the molten slag is cooled and solidified at the slag discharge port. Can be prevented.

Further, in this incineration ash melting apparatus, the plasma torch is arranged above the slag discharge port, the plasma torch is tilted by the tilting device, and the plasma arc irradiation area is the slag discharge port from the ash charging side wall surface of the slag bath. Since the plasma torch is located at the edge portion of the melting furnace without being directly above the molten slag, the influence of radiant heat of the molten slag is reduced.

〔Example〕

An embodiment of a melting treatment apparatus for incinerated ash according to the present invention will be described below with reference to the drawings.

In FIG. 1, an example of this melting processing apparatus for incinerated ash is shown. This incinerator ash melting treatment equipment is
Incinerator ash generated by incinerating sewage sludge or other wastes in an incinerator, and in some cases, dust collected by a dust collector in the incinerator system is mixed in a melting furnace, that is, a plasma arc furnace 5. It is melted and mainly comprises a plasma arc furnace 5, a plasma torch 8 provided in the plasma arc furnace 5, and a plasma system 1 for generating plasma in the plasma torch 8.

As shown in FIG. 1, the plasma system 1 mainly includes a plasma arc torch 8, a power supply device 4 that switches the alternating current to a direct current and supplies the direct current to the plasma torch 8,
A control device 26 for generating a plasma arc by the plasma torch 8 and controlling for stable supply of the plasma arc, a cooling water supply device 27 for supplying cooling water for cooling the electrode and the torch body, and a plasma forming gas. It has an air supply device 28 for supplying the air A that becomes

As shown in FIG. 2, on one side of the furnace lid 7 of the plasma arc furnace 5, there is provided an ash hopper 12 into which the incinerated ash generated from the incinerator or the dust B collected from the dust collector is put. Ash supply device 3 from the ash hopper 12 through the chute 9
Is continuously or intermittently charged into the plasma arc furnace 5. The plasma arc furnace 5 is provided with a water-cooled fixed-type furnace lid 7 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. A plasma torch 8 is provided on the other side of the furnace lid 7 of the plasma arc furnace 5, and a slag discharge port 25 is formed in the furnace body 6 below the plasma torch 8. The slag discharge port 25 communicates with the slag receiving container 15 arranged below and the exhaust gas duct 23 extending upward.

Further, the plasma torch 8 is attached to the furnace lid 7 by a torch elevating device for moving the plasma torch 8 in the axial direction, that is, a driving device 11, so that the plasma torch 8 can be set at a predetermined position in the furnace body 6. Is configured.

Further, the plasma torch 8 is provided with a tilting device 2 for changing the tilt of the plasma torch 8 in order to change the irradiation direction of the plasma torch 8. By driving the tilting device 2, the direction of the plasma torch 8 can be changed. Then, the irradiation area of the plasma from the plasma torch 8 can be set so as to include the slag discharge port 25 of the plasma arc furnace 5.

The plasma arc furnace 5 in the apparatus for melting incinerated ash according to the present invention is configured as described above and operates as follows.

In the plasma arc furnace 5, the plasma torch 8 operates the drive device 11 so as to change the distance from the incineration ash B to the plasma torch 8 according to a predetermined voltage or power amount of the plasma torch 8. The driving device 11 is a plasma torch 8
Is moved up and down in the axial direction, that is, in the direction of arrow R, and is composed of, for example, a double-acting cylinder. The drive device 11 operates the hydraulic device in response to a command from the control device 26 to move the plasma torch 8 so as to be able to move up and down relative to the furnace lid 7 in the axial direction. For example, the plasma torch 8 is lowered into the plasma arc furnace 5 and the plasma torch 8 is moved to the opposite electrode.
When a predetermined distance is set with respect to 10, the discharge of the plasma torch 8 is completed, and the melting process of the incineration ash B is completed, the driving device 11 raises the furnace lid 7 again.

Further, the plasma torch 8 is configured to be swingable, that is, tiltable over a tilting angle θ by the tilting device 2. The tilting device 2 is configured to be rotatable or pivotable in the direction of arrow Q about a pivot 35 by a ball joint or the like, so that the plasma torch 8 is pivoted or tilted over a tilting angle θ. become. Therefore, the tilting device 2 operates upon receiving a command from the control device 26, and the tilting device 2 rotates the plasma torch 8 to change the plasma irradiation area. This plasma irradiation region is set so as to extend from the ash-introducing side wall surface of the slag bath, that is, the molten slag 13 to the tip of the slag discharge port 25. In this case, the plasma torch 8 and the driving device 11 fixing the plasma torch 8 are tilted together.

Therefore, one plasma torch 8 performs the melting action of the incineration ash B and the heating action of the slag discharge port 25 of the furnace body 6, prevents the molten slag from solidifying at the slag discharge port 25, and continuously generates the slag. It can be discharged.

The molten slag flowing out from the slag discharge port 25 is received and discharged in the slag receiving container 15, but when the slag discharge port 25 is cooled by the air leaking from the gap between the slag receiving container 15 and the furnace body 6, the plasma torch 8 Frequently slag outlet
You have to tilt it towards 25. The exhaust gas outlet 16 is installed below the slag outlet 25 and close to the slag receiving container 15, and exhaust gas and leaked air are sucked into the exhaust gas outlet 16 to prevent cooling of the slag outlet 25, and the plasma torch 8 The time to heat the slag outlet 25 is shortened,
If the plasma torch 8 is configured so that most of the plasma energy is used for melting the incineration ash B, the plasma arc furnace 5 can provide an energy-saving device.

The part where the incineration ash B is supplied by the ash supply device 3 is the incineration ash B
Since the amount of heat (heat energy) for heating to the melting temperature and the heat of fusion of the incineration ash B are supplied, the required amount of heat is large. On the other hand, it is sufficient for the portion of the slag discharge port 25 to give a heat amount (heat energy) such that the molten slag does not cool, and the required heat amount is small. In addition, the slag bath 13 has a slag depth of 200 mm or more, while the slag discharge port 25 has a slag depth of 50 mm or less, so if the amount of heat obtained from the plasma torch is too large, the slag is discharged. There is also a risk of burning the refractory material forming the outlet 25.

As shown in FIG. 2, when the ash supply device 3 and the slag discharge port 25 are arranged at positions opposite to each other in the plasma arc furnace 5, and the plasma torch 8 is arranged immediately above the slag discharge port 25, the slag discharge port 25 and The distance between the tip of the plasma torch 8 is the shortest, and the distance between the surface of the slag bath 13 at the bottom wall of the ash feeder and the tip of the plasma torch 8 is always the longest. As a result, the slag discharge port 25 always receives the minimum amount of heat, and the ash supply device 3
A maximum amount of heat can be given to the slag bath 13 below the slag bath 13 and the thermal energy of the plasma can be adjusted appropriately. Further, when the plasma torch 8 is arranged above the center of the slag bath 13, the plasma torch 8 itself receives the radiant heat from the slag bath 13 and there is a high risk that the plasma torch 8 will burn out. By disposing the plasma torch 8 above the slag discharge port 25, it is possible to prevent the plasma torch 8 from being burned and to extend the life of the plasma torch 8.

Further, the plasma torch 8 used in this plasma incineration ash melting apparatus has two types of arc discharge types, a transfer type as shown in FIG. 3 or a non-transfer type as shown in FIG. Things that can be used. The transfer type requires a negative counter electrode, and the non-transfer type does not require a negative counter electrode other than the plasma torch since the plasma torch tip is opposed. The thermal efficiency of the plasma torch 8 body is
92-94%, non-transfer type is 85%, the transfer type is superior in terms of thermal efficiency, and the non-transfer type that does not require a counter electrode is superior in terms of ease of handling.

For example, as shown in the figure, when the plasma torch 8 is arranged above the sprue part 25 and a transfer type arc discharge type is used, the counter electrode of the plasma torch 8 is attached to the bottom of the furnace body 6.
Structure to embed 10. Electrode (+ electrode) built in the plasma torch 8 and counter electrode 10 provided at the bottom of the furnace body 6
A plasma arc is generated between the (-) pole. The plasma torch 8 has a cable 17 connected to the positive pole from the power supply device 4.
To the plasma torch 8 via the
To the counter electrode 10 which is a graphite electrode, and a predetermined voltage is applied between the plasma torch 8 and the counter electrode 10. 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 as a result.

In the case of the non-transfer type, the counter electrode of the graphite electrode is unnecessary, and one electrode is connected to the electrode built in the plasma torch 8 through the cable 18. To generate plasma in the plasma torch 8 is achieved by the function of the 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 V /
The voltage increases at a rate of cm. Since the electric current of the plasma torch 8 is controlled to be constant by the command of the control device 26, the amount of electric power is proportional to the distance, and the longer the distance, the more the power consumption increases and the amount of heat given to the melted matter, that is, the incinerated ash B increases. . At this time, the current is PID controlled and the voltage is determined only by the distance between the counter electrodes and the variation cycle of the arc gas pressure in the case of the transfer type plasma torch 8.

Further, in the case of the non-transfer type plasma torch, it is determined by the variation cycle of the arc gas pressure. When the transfer type plasma torch 8 is used, the incineration ash B is melted by generating a plasma arc between the + pole and the − pole slag bath built in the plasma torch 8. . When a non-transfer type plasma torch is used, a plasma arc is generated between the positive electrode and the negative electrode of the plasma torch, and the incinerated ash B is melted by the arc heat, that is, plasma energy.

Further, the cooling water pump 29 in the cooling water supply device 27 is operated, the cooling water is sent from the water tank 30 to the heat exchanger 33, and heat is exchanged in the heat exchanger 33, and then the heat exchanger 33 is used to manifold 34, Then, the plasma torch 8 is supplied through the cooling water pipes 19 and 20 to cool the plasma torch 8.

Further, the air compressor of the air supply device 28 is operated, and compressed air is supplied from the manifold 34 to the plasma forming air pipe 21.
Through the plasma torch 8.

In the incinerator ash melting apparatus according to the present invention, incinerated ash B generated from the incinerator or dust B collected from the dust collector
Is charged into the ash hopper 12, and the incinerated ash B is continuously or intermittently charged into the plasma arc furnace 5 through the chute 9. Further, in order to generate a plasma arc, a high-energy pulse is applied between the electrodes built in the plasma torch 8 under a predetermined setting condition for discharging the plasma arc to generate a pilot arc.

Then, after the main arc is generated, by setting a predetermined current (for example, 200 to 300 A) and a predetermined voltage (for example, 400 to 500 V), the thermal energy of the plasma arc is incinerated ash 13 which is the object to be heated. Given to. When the plasma torch 8 is a transfer type, in order to generate the main arc, the tip of the plasma torch 8 and a counter electrode, which is a graphite electrode, are used.
The distance of 10 must lie in the range 25mm to 75mm. After the main arc occurs, the tip of the plasma torch 8 and the counter electrode 10
Since the gaps are electrically connected by the plasma flow, the driving device 11 is operated to raise the plasma torch 8 to increase the output, but the plasma is not interrupted even if the distance between the electrodes is 75 mm or more. Slag bath or molten slag 13 is
Since it also serves as the counter electrode 10 of the plasma torch 8, it requires a certain depth. If the molten slag 13 is too shallow,
Since the incinerated ash B is not melted and becomes mountain-shaped on the surface of the slag bath, the conductivity is lost and the plasma arc is interrupted. On the other hand, if it is too deep, the lower part of the molten slag 13 will be solidified.

Therefore, the depth of the molten slag 13 is preferably in the range of 100 to 400 mm.

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 incineration ash B containing oxides, highly molten substances, etc. by radiation or conduction, and the incineration ash B is generated in the slag bath. It is heated and melted by the plasma arc generated by the plasma torch 8 to become molten slag, that is, molten slag 13, and the metal as molten metal is continuously or intermittently discharged from the sprue 25 of the furnace body 6 to form the slag S. As a result, it is taken out to the slag yard 14. The molten slag S that has flown out is received by the slag receiving container 15, and when the slag receiving container 15 is filled with the slag S, the slag S is discharged to the outside of the furnace by replacing it with another slag receiving container 15. Further, the combustion gas G 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 processing device (not shown), and then sucked and discharged from the exhaust gas processing device by an induction fan. To be done.

〔The invention's effect〕

The apparatus for melting incinerated ash according to the present invention is configured as described above and has the following effects. That is, the incineration ash melting apparatus is provided with a plasma torch arranged in a melting furnace for generating a plasma arc, a drive device for moving and adjusting the plasma torch in the axial direction, and an irradiation direction of the plasma torch. Of the tilting device for changing and adjusting the tilt of the plasma torch, and changing the direction of the plasma torch so that the irradiation region of the plasma arc from the plasma torch includes the slag discharge port of the melting furnace by driving the tilting device. Since the plasma torch is tilted and the slag discharge port is heated by a plasma, the molten slag is continuously passed through the slag discharge port without using extra energy such as an auxiliary burner. Can be discharged smoothly. Since the molten slag can be continuously discharged, it is not necessary to retain the slag in the furnace for a long time like a tap type melting furnace, so that the volume of the furnace body can be made small, and the plasma arc can be economically inexpensive. A furnace can be provided.

Particularly, since the exhaust gas outlet is provided in the lower part of the slag discharge port, and the slag receiving container serving as a pool of the discharged slag is arranged below the slag discharge port, the slag discharge port is effectively heated by the radiant heat of the high temperature exhaust gas. Therefore, the phenomenon of cooling and solidification of the molten slag at the slag discharge port can be prevented.

Further, incinerator ash containing a high-melting point substance discharged from the incinerator is directly put into the melting furnace in sequence, and air is supplied as a plasma forming gas to the plasma torch provided in the melting furnace to generate a plasma arc, The thermal energy of the plasma arc can be applied to the incineration ash by radiation or conduction to rapidly melt the incineration ash. Furthermore, since a plasma arc is used instead of the conventional normal arc, a stable and high temperature can be obtained, and since there is almost no fluctuation in electric power, the influence on the power supply is small.

Further, since the plasma torch is disposed above the slag discharge port in this incinerator ash melting apparatus, 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 saving. Even if it is cooled by cold air, the slag can be discharged by heating it with a plasma arc, so there is no need to completely seal the slag discharge port with a water seal, so an gradually cooled slag with a higher hardness than granulated slag can be obtained. The range of effective use of slag is expanded.

Further, the ash supply device and the slag discharge port may be arranged at opposite edges of the plasma arc furnace, and by disposing the plasma torch directly above the slag discharge port, the slag discharge port Gives the minimum amount of heat,
It is also possible to appropriately adjust the distribution of energy so that the ash supply port side gives the maximum amount of heat. Moreover, by arranging the plasma torch directly above the slag discharge port, the radiant heat that the plasma torch receives from the slag bath becomes smaller than when it is arranged above the slag bath, and the burning of the plasma torch due to the radiant heat occurs. Can be prevented.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an example of an apparatus for melting incinerated ash according to the present invention, and FIG. 2 is a sectional view showing an example of a plasma arc furnace of the apparatus for melting incinerated ash according to the present invention.
FIG. 3 is an explanatory view for explaining a transfer type plasma torch used in the plasma arc furnace of FIG. 2, and FIG.
It is explanatory drawing explaining the non-transfer-type plasma torch utilized for the plasma arc furnace of the figure. 1 ... Melt processing device, 2 ... Tilt device, 5 ... Plasma arc furnace (melting furnace), 6 ... Furnace body, 7 ... Furnace lid, 8 ...
Plasma torch, 10 …… Counter electrode, 11 …… Drive device, 13 ……
Molten slag, 25 …… Slag discharge port, B …… Incineration ash.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiro Amamiya 1-6-27 Konan, Minato-ku, Tokyo Within EBARA IN FILCO CORPORATION (72) Inventor Akira Miyamura 4-2-1 Motofujisawa, Fujisawa-shi, Kanagawa Stock company Ebara Research Institute (56) References JP 64-6611 (JP, A) JP 59-142374 (JP, A) Actual 60-86731 (JP, U) JP 59- 16199 (JP, B2)

Claims (2)

[Claims] 1. A plasma torch for generating a plasma arc provided in a melting furnace, a slag discharge port for discharging molten slag provided on a side wall of a furnace body of the melting furnace, and a melt discharged by dropping from the slag discharge port. A slag receiving container arranged below the slag discharge port for receiving slag, an exhaust gas duct for opening an exhaust gas outlet of exhaust gas between the slag discharge port and a slag receiving container below the slag discharge port, and the plasma A drive device for moving and adjusting the plasma torch in the axial direction of the torch, and an irradiation area of the plasma torch is changed by changing the irradiation direction of the plasma arc in the melting furnace so that the melting slag surface and the slag discharge inside the furnace body are changed. And a tilting device for changing and adjusting the direction of the plasma torch so as to include the entire area of the outlet. Melt processing apparatus of ash. 2. The plasma torch is arranged above the slag discharge port of the melting furnace.
The apparatus for melting incinerated ash according to item 1.