JPH11108331A - Ash melting furnace base metal discharge device - Google Patents

Abstract

(57) [Summary] [Problem] To facilitate the work of discharging base metal. SOLUTION: Discharge pool 2 is provided on the outer surface of side wall 1a of furnace body 1.
In addition, a discharge passage 22 is formed in the side wall 1a corresponding to the discharge pool 24 so as to open toward the bottom of the base metal 5, so that the melting chamber 2 and the discharge pool 24 communicate with each other. An electromagnetic induction device 27 that is disposed on at least a part of the furnace wall and moves the base metal 5 between the discharge pool 24 and the melting chamber 2 by a moving magnetic field that passes through the base metal 5; The furnace 1 was tilted to lower the discharge pool 27 downward, and a furnace tilting device 31 capable of discharging the base metal 5 was provided. An electromagnetic induction device for preventing solidification of the base metal in the drain pool can be built into the furnace main body, so that when the base metal is discharged, there is no need for a removal operation like an external device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for discharging a base metal of a ash melting furnace of a plasma type or an arc type in which a base metal is stored as a conductor at the bottom of a melting chamber.

[0002]

2. Description of the Related Art The incineration ash introduced into an ash melting furnace has its iron removed by a magnetic separator in the previous process, but it is impossible to completely remove metals. It is thrown. In addition, non-magnetic steel such as stainless steel, which cannot be sorted by the magnetic separator, is put into the ash melting furnace together with the incineration ash,
As the amount of ash melting increases, the metals in the ash dissolve into the base metal and increase. Thereby, the layer of the molten slag discharged at a certain level on the base metal becomes thin, and in the case of a plasma type ash melting furnace, the plasma arc becomes unstable. For this reason, Japanese Unexamined Patent Publication No. 9-4836 discloses an apparatus in which the operation is stopped when the molten metal surface of the base metal reaches the upper limit level, the furnace body is tilted, and the base metal is discharged from the slag outlet.

[0003]

In the above-described base metal discharging device, a heating device such as a burner or a heating electrode is installed in order to prevent solidification of the base metal in a basin formed outside the furnace body. It is necessary to remove the heating device when discharging the base metal. Therefore, there has been a problem that the work of discharging the base metal becomes complicated.

[0004] It is an object of the present invention to solve the above-mentioned problems and to provide a base metal discharging device of an ash melting furnace which can easily discharge a base metal.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention forms a discharge passage which is opened to the bottom of a base metal on a side wall of a furnace body and discharges the discharge passage to an outer surface of a side wall of the furnace body. An electromagnetic discharge hole provided in the furnace wall of at least a part of the discharge passage, the electromagnetic field being provided between the discharge pool and the melting chamber by a moving magnetic field passing through the base metal; A furnace guiding device is provided, and a furnace tilting device capable of tilting the furnace body to lower the discharge pool and discharge the base metal is provided.

According to the above configuration, the base metal is fluidized by utilizing the Lorentz force generated by the moving magnetic field generated by the electromagnetic induction device so as to pass through the inside of the base metal. By circulating the base metal between them, it is possible to prevent solidification of the base metal in the discharge pool and the discharge passage. In addition, since the electromagnetic induction device is composed of a magnetic field forming coil and a power supply circuit that can be built into the furnace wall of the discharge path and the discharge pool, when an auxiliary burner or auxiliary electrode for preventing coagulation that becomes an obstacle during tilting is provided. The furnace body can be easily tilted and the base metal can be discharged as compared with the case where the removal operation is required.

According to a second aspect of the present invention, in the above structure, the heat conduction is built up from the position corresponding to the surface of the molten slag to the weir body for preventing the molten slag from flowing out of the melting chamber above the discharge passage. A dam cooling device including a block and a cooling fluid passage formed at a position remote from the surface of the molten slag in the heat conducting block and sending a cooling fluid is provided.

According to the above construction, even if a high-temperature base metal always flows in by the electromagnetic induction device, the heat conduction block is built in the weir wall, so that it is effectively cooled to prevent burning and the like. In addition to this, the cooling means is provided at an outer portion away from the base metal and the molten slag, so that safety can be improved.

According to a third aspect of the present invention, a discharge passage is formed in the side wall of the furnace main body so as to face the bottom of the base metal, and a discharge basin communicating with the discharge passage is provided on the outer surface of the side wall of the furnace main body. An electromagnetic induction device that is built into at least a part of the furnace wall of the discharge passage and moves the base metal between the discharge pool and the melting chamber by a moving magnetic field that passes through the base metal; The reservoir is provided with a discharge weir for discharging the base metal overflowing beyond a certain level.

According to the above configuration, the base metal is fluidized by utilizing the Lorentz force generated by the moving magnetic field generated by the electromagnetic induction device so as to pass through the inside of the base metal. By circulating and moving the base metal between the base and the base, solidification of the base metal in the discharge pool and the discharge passage can be prevented, and the base overflowing above a certain level by the discharge weir provided in the discharge pool Since the metal is constantly discharged, there is no need to periodically tilt the furnace. Therefore, continuous operation can be efficiently performed without the need for periodic base metal discharge work, and the safety of the work can be improved since large-capacity base metal is not handled. Also, a large output jack for tilting the furnace is not required, and the equipment cost can be reduced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a plasma type ash melting furnace according to the present invention will be described below with reference to FIGS.

In this plasma type ash melting furnace, as shown in FIG. 1, a pair of electrodes, a positive electrode 3A and a negative electrode 3B are provided on the top wall of a furnace body 1 in which a melting chamber 2 is formed so as to be able to move up and down. And
A DC voltage is applied to both electrodes 3A, 3B from a power source 4 and gas supply holes 3 formed in both electrodes 3A, 3B are formed.
The plasma working gas is supplied into the melting chamber 2 from the gas supply holes (not shown) provided in the furnace body 1 and the electrodes 3A, 3B and the bottom of the melting chamber 2 is accommodated. A plasma arc is formed with the base metal 5, and the heat is used to heat and melt ash A discharged from a refuse incinerator or the like.

An ash supply port 8 for supplying ash A from an ash supply hopper 6 via an ash pusher 7 is formed on one side of the furnace body 1. At the other end of the furnace main body 1, a slag outlet 9 for discharging molten slag S generated by heating and melting the ash A by the plasma arc is formed, and the molten slag S is discharged from the slag outlet 9 through the slag outlet 9. It is configured to be charged into a granulation pit 11 arranged below the cooling chamber 10 to form granulated slag.

The furnace body 1 has a metal discharge portion 21 formed on the side wall 1a and a bottom portion of the furnace body 1 in order to adjust the level of the base metal 5 which increases due to metals mixed into the ash A. And a tilting device 31 disposed at the bottom. In FIG. 1, the metal discharge unit 21 is shown below the ash supply port 8, but is not limited to this.

As shown in FIGS. 2 and 3, the metal discharge portion 21 has a discharge passage 22 formed through the side wall 1a at a position where the bottom surface 22a is continuous with the bottom wall 1b and facing the bottom of the base metal 5. A discharge pool 24 formed on the outer surface of the side wall 1a by the pool forming wall 23; a dam cooling device 26 built in a dam 25 for separating the molten slag S above the discharge passage 22; An electromagnetic induction device 27, which is built in the bottom 22 a of the base 22 and circulates and flows through the base metal 5 between the melting chamber 2 and the discharge pool 24 by a moving magnetic field that passes through the base metal 5.

The weir cooling device 26 serves to extend the life of the weir 25 for blocking the molten slag S and prevent steam explosion due to leakage of cooling water as a cooling medium.
The refractory material 25a having a high thermal conductivity is thinly applied on the surface of 6a, and the service life of the molten slag S is extended by the self-fringing effect. The lower end of the copper block 26a
A cooling water flow path 26b is formed in an upper portion of the copper block 26a, which is separated from the surface of the molten slag S and reaches between the surface ML of the base metal 5 and the surface SL of the molten slag S.
Instead of this form, as shown in FIGS. 4 and 5, a cooling water channel 26c extending above and near the position corresponding to the surface of the molten slag S may be formed in the copper block 26a.

The electromagnetic induction device 27 is based on the principle of a so-called electromagnetic trough using a one-sided linear motor. The moving magnetic field generation units 27a and 27b, which are stators, form a primary side. The next conductor is the base metal 5 itself. The moving magnetic field generators 27a and 27b for the forward path and the return path each include an iron core and a coil, form a moving magnetic flux passing through the base metal 5, generate an electromagnetic pressure, and move the base metal 5 in the directions of arrows A and B. Move to As a result, the base metal 5 in the drain pool 24 is fluidized and circulated between the base metal 5 and the melting chamber 2.
The solidification of the base metal 5 inside can be prevented.

In the tilting device 31, a receiving member 32 disposed at the bottom of the furnace body 1 on the side of the metal discharge portion 21 is rotatably supported by a support 33 installed on the hearth. On the other hand, the bottom of the furnace body 1 opposite to the receiving member 32 is
4 so as to be able to move up and down, so that the discharge pool 24 of the metal discharge unit 21 is lowered.

In the above configuration, the gas supply holes 3a, 3b
A plasma working gas such as a nitrogen gas is supplied to the melting chamber 2 and the like, a voltage is applied to both electrodes 3A and 3B, and a plasma arc is formed between the electrodes 3A and 3B and the base metal 5 to form a base. The metal 5 is preheated and melted. When the temperature reaches a predetermined temperature, the ash A in the ash supply hopper 6 is supplied from the ash supply port 8 onto the base metal 5 by the ash pusher 7 and is heated and melted. Then, when the molten slag S reaches a certain level, the molten slag is discharged from the slag outlet 9 to the granulation pit of the slag cooling chamber 10 and is cooled with water to produce granulated slag. As the amount of ash melting increases, the metals contained in the ash leach and mix with the base metal 5, and the base metal 5 gradually increases.

At this time, the base metal 5 in the discharge pool 24 is fluidized and circulated with the melting chamber 2 by the action of the electromagnetic induction device 27, so that solidification is prevented beforehand. Further, the weir 25 to which the high-temperature base metal 5 comes into contact is formed by the copper block 26 a of the weir cooling unit 26 and the cooling water flow hole 26.
With b, the life extension is promoted by utilizing the self-flying effect and the steam explosion is prevented.

When the surface ML of the base metal 5 in the melting chamber 2 reaches the upper limit, the operation is stopped and the furnace body 1 is tilted by the tilting device 31 as shown by the phantom line in FIG. The surface ML of the base metal 5 in the pool 24 is raised, and only the base metal 5 is discharged. Then, after discharging the predetermined amount, the furnace main body 1 is returned to the horizontal posture by the tilting device 31, and the discharge of the base metal 5 is completed. Then, the operation is restarted.

According to the above-described embodiment, the electromagnetic induction device 27 for flowing and circulating the base metal 5 between the melting chamber 2 and the discharge pool 24 by the moving magnetic field at the bottom of the discharge passage 22.
As a result, since the solidification of the base metal 5 is prevented, when a burner or a torch for preheating the base metal 5 of the discharge pool 24 is provided outside when the base metal 5 is discharged, a removal operation is required. In comparison, the discharge operation can be performed easily and quickly.

Weir 25 for damping molten slag S
Is provided with a weir body cooling device 26 having a copper block 26a and a cooling water flow path 26b.
The self-fringing effect is generated on the surface of the weir body 25 that flows and comes into contact with the dam body 25, and the life can be prolonged.

Next, a second embodiment of the ash melting furnace will be described with reference to FIGS. The same members as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. The tilting device 31 is not provided in the furnace main body 1 of the ash melting furnace, but is supported by a frame 41 in a fixed state. In the discharge pool 24, a discharge weir 42 in which a discharge groove 42a is formed at a position lower than the upper limit level of the molten metal surface of the base metal 5.
Is provided so that the base metal 5 overflowing beyond the level of the discharge groove 42a is always discharged. The discharge weir 42 is formed such that the outlet end protrudes, and the base metal 5 overflowing from the discharge well 24 is dropped from the discharge groove 42a into the hood 43 and discharged to the metal cooling water tank 44. The paper is discharged to a discharge tray 46 by the scraper conveyor 45.

Such a structure is most suitable for a large ash melting furnace. When the amount of melting ash increases, the amount of the base metal 5 also increases, and the base metal 5 is continuously discharged from the discharge groove 42a. No solidification.

According to the above embodiment, since the base metal 5 overflowing a certain level by the discharge weir 42 is always discharged, the operation of stopping the furnace, tilting, discharging the base metal 5, and restarting is unnecessary. And stable continuous operation can be performed efficiently. In addition, when handling a large volume of base metal on a regular basis, safety is an issue. However, the amount of discharged base metal that is constantly handled is small, and the safety of work can be improved. In addition, a large furnace requires a tilting jack having a large output. However, since there is no need to tilt the furnace, equipment costs can be reduced.

In the above embodiment, the electromagnetic induction device 27 is provided with the traveling magnetic field generating sections 27a for the forward path and the return path.
27b is provided, but it is sufficient if a magnetic pressure causing flow circulation is generated in the base metal 5, and one of the forward and return paths, the bottom of the pool wall 23, the side of the discharge passage 22, and a combination thereof. Alternatively, a moving magnetic field generating unit may be provided.

[0028]

As described above, according to the first aspect of the present invention, the moving magnetic field generated by the electromagnetic induction device so as to pass through the base metal and the Lorentz force generated by the moving magnetic field are utilized. By fluidizing the base metal and circulating the base metal between the discharge pool and the melting chamber, solidification of the discharge pool and the base metal in the discharge passage can be prevented. Also, since the electromagnetic induction device is constituted by a magnetic field forming coil and a power supply circuit that can be built into the furnace wall of the discharge path and the discharge pool, compared to an auxiliary solidification prevention burner or an auxiliary electrode that becomes an obstacle when tilting, The base metal can be easily discharged by tilting the furnace body.

According to the second aspect of the present invention, even if the high-temperature base metal always flows in by the electromagnetic induction device, the heat conduction block is built in the weir wall.
Effective cooling prevents burnout etc.
Since the cooling means is provided at an outer portion away from the base metal and the molten slag, safety can be improved.

According to the third aspect of the present invention, the base metal is fluidized by utilizing the Lorentz force generated by the moving magnetic field generated by the electromagnetic induction device so as to pass through the base metal, and the drain pool is discharged. By circulating and moving the base metal between the furnace and the melting chamber, it is possible to prevent solidification of the base metal in the discharge sump and the discharge passage, and to maintain a certain level by the discharge weir provided in the discharge sump. Since the overflowed base metal is constantly discharged, there is no need to periodically tilt the furnace. Therefore, continuous operation can be efficiently performed without the need for periodic base metal discharge work, and the safety of the work can be improved since large-capacity base metal is not handled. Also, a large output jack for tilting the furnace is not required, and the equipment cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a plasma type ash melting furnace according to the present invention.

FIG. 2 is a longitudinal sectional view showing a discharge pool of the ash melting furnace.

FIG. 3 is a plan view showing an electromagnetic induction device of the ash melting furnace.

FIG. 4 is a longitudinal sectional view showing another embodiment of the dam cooling device of the ash melting furnace.

FIG. 5 is a rear view showing the dam body cooling device.

FIG. 6 is a longitudinal sectional view showing a second embodiment of the plasma ash melting furnace according to the present invention.

FIG. 7 is a longitudinal sectional view showing a discharge weir of the ash melting furnace.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Furnace main body 2 Melting chamber 3A Positive electrode 3B Positive electrode 4 Power supply 5 Base metal 9 Slag outlet 21 Metal discharge part 22 Discharge passage 24 Discharge pool 25 Weir body 26 Weir body cooling device 26a Copper block 27 Electromagnetic induction device 27a, 27b Moving magnetic field generator 31 Tilt device 34 Tilt jack 42 Discharge weir 42a Discharge groove 43 Metal cooling water tank S Molten slag

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Tadashi Kawano 5-28, Nishikujo, Konohana-ku, Osaka-shi, Osaka Inside Hitachi Zosen Corporation (72) Inventor Tsuneharu Sakakibara 5-chome, Nishikujo, Konohana-ku, Osaka-shi, Osaka No. 3-28 Inside Hitachi Zosen Corporation (72) Katsuya Norito 5-28 Nishikujo, Konohana-ku, Osaka City, Osaka Prefecture 3-72 Inside Hitachi Zosen Corporation (72) Tsutomu Kuwahara, Nishi Konohana-ku, Osaka City, Osaka Prefecture Hitachi Shipbuilding Co., Ltd. (72) Inventor Hirofumi Kosaka 5-93 Kujo 3-chome, Nishikujo, 3-chome, Konohana-ku, Osaka, Japan

Claims (3)

[Claims] A discharge passage formed in a side wall of the furnace body facing the bottom of the base metal; and a discharge basin communicating with the discharge passage provided on an outer surface of the side wall of the furnace body, wherein at least one of the discharge passages is provided. An electromagnetic induction device that is built into the furnace wall of the section and moves the base metal between the discharge pool and the melting chamber by a moving magnetic field that passes through the base metal; A base metal discharging device for an ash melting furnace, characterized in that a furnace tilting device capable of lowering the temperature downward and discharging the base metal is provided. 2. A heat conduction block built up from a position corresponding to the surface of the molten slag to a weir body for preventing the molten slag from flowing out of the melting chamber at an upper portion of the discharge passage; 2. A base metal discharging device for an ash melting furnace according to claim 1, further comprising a weir body cooling device provided with a cooling fluid passage formed at a position remote from the surface of the slag and for sending a cooling fluid. 3. A discharge passage opened on the side wall of the furnace body facing the bottom of the base metal, and a discharge basin communicating with the discharge passage is provided on an outer surface of the side wall of the furnace body, wherein at least one of the discharge passages is provided. An electromagnetic induction device that is built into the furnace wall of the section and moves the base metal between the discharge pool and the melting chamber by a moving magnetic field that passes through the base metal is provided. A base metal discharge device for an ash melting furnace, comprising a discharge weir for discharging overflowed base metal.