JP3714384B2 - Ash melting furnace - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tapping apparatus for an ash melting furnace that melts and solidifies fly ash and incineration ash generated when municipal waste and industrial waste are incinerated.
[0002]
[Prior art]
Wastes such as municipal waste and sewage sludge were incinerated at an incineration facility, and the resulting fly ash and incineration ash were conventionally disposed of in landfills. However, there is a problem of depletion of landfill sites and groundwater contamination due to the elution of toxic heavy metals, so the need for weight reduction / volume reduction and detoxification by melting is increasing.
[0003]
Against this background, an ash melting furnace has been proposed that melts fly ash and incineration ash discharged from incinerators that use residual carbon, coke, kerosene, and electric power as heat sources. Processing is in progress. Among these, there are a plasma arc heating method and an electric resistance heating method as an ash melting furnace using electric power as a heat source.
[0004]
FIG. 3 is a longitudinal sectional view of a conventional electric resistance ash melting furnace.
In the figure, a is an ash melting furnace. b is an ash melting chamber. c is an outlet that overflows the molten slag j provided in the middle of the ash melting furnace a. d is a metal discharge port provided in the lower part of the ash melting furnace a. e is a main electrode provided on the top of the ash melting furnace a, and f is a furnace bottom electrode provided on the bottom of the furnace so as to be opposed to the main electrode e. g is an ash charging port provided at the top of the ash melting furnace a, and the fly ash and incinerated ash conveyed by a conveyor (not shown) are charged into the ash melting chamber b. h is an exhaust gas outlet provided at the top of the ash melting furnace a. i is an ash solid layer such as fly ash or incinerated ash charged into the ash melting chamber b. k is a metal layer. m is a power source for flowing DC electricity between the main electrode d and the furnace bottom electrode e, and n and o are the electric wires.
[0005]
[Problems to be solved by the invention]
The continuous tapping of molten slag caused by the overflow of the ash melting furnace is used in many ash melting furnaces because of its good operability. However, when unloading, unmelted ash floating on the molten slag flows along with the molten slag along with the molten slag. Moreover, when the viscosity of molten slag is high, it cannot flow out smoothly from the spout opening, and the spout opening may be blocked. Furthermore, there is a problem that outside air flows into the ash melting chamber from the tap.
[0006]
The present invention was devised to solve the above-described problems, and the outlet of the ash melting furnace is made of cartridge bricks so that the outlet can be easily replaced, and on the molten slag. In addition to preventing the outflow of unmelted ash that has surfaced, the inflow of outside air into the ash melting chamber is prevented, and the molten slag is heated in the vicinity of the tap to control the flow rate, and then discharged to control The purpose is to stabilize the operation.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, an ash melting furnace for performing ash melting by applying a direct current between a main electrode inserted from the furnace top and a furnace bottom electrode provided at the furnace bottom, It has an outlet that overflows the molten slag provided in the middle of the furnace wall, and a metal outlet that is provided in the lower part of the furnace wall. The outlet has a cylindrical outlet with a through hole in the center. Fence brick, insulation brick provided to surround the extraction brick, and provided to cover the insulation brick from above, projecting to the ash melting chamber side, and the lower end is immersed in the molten slag The upper electrode brick with a cross-section horseshoe shape that prevents the outflow of unmelted ash that has floated on the molten slag and embedded in the insulating brick so that the tip is exposed in the ash melting chamber, Removable and integrated with the lower electrode brick provided below It is constituted by the cartridge brick, ash melting furnace that are enabled energization between the upper electrode brick and the lower electrode brick is provided.
[0008]
Next, the operation of the present invention will be described.
Fly ash and incinerated ash charged into the ash melting chamber of the ash melting furnace are energized and heated to a main electrode and a furnace bottom electrode disposed in the ash melting chamber to form molten slag. The outlet of the ash melting furnace is provided in the middle of the furnace wall, and the molten slag overflows from the outlet and is continuously discharged. When molten slag comes out, unmelted ash that has floated on the molten slag is prevented from flowing out by an upper electrode brick having a horseshoe-shaped cross section whose lower end is immersed in the molten slag, and inflow of outside air is prevented. In addition, the molten slag is energized and heated to the upper electrode brick and the lower electrode brick at the tap outlet, the viscosity is adjusted, and the flow rate is controlled. Moreover, since the spout is formed of a cartridge brick that can be inserted and removed, maintenance can be easily performed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of the present invention, which is a longitudinal sectional view of an ash melting furnace according to the present invention, FIG. 2 (A) is an enlarged side view of a taphole, and FIG. It is an AA arrow line view.
[0010]
1 and 2, 1 is an ash melting furnace for melting fly ash and incinerated ash, and 2 is an ash melting chamber. Denoted at 3 is an outlet for overflowing the molten slag 12 provided in the middle of the furnace wall of the ash melting furnace 1 and continuously discharging the molten slag 12. As shown in FIG. 2, the spout 3 includes a cylindrical spout brick 4 having a through-hole 4 a in the center, insulating bricks 7 provided so as to surround the spout brick 4, and this insulation The brick 7 is provided so as to cover the ash melting chamber 2 from the top, and the lower end 5a is immersed in the molten slag 12 so as to prevent the unmelted ash 11 floating on the molten slag 12 from flowing out. The upper electrode brick 5 having a horseshoe shape in cross section and the lower electrode brick 6 embedded in the insulating brick 7 so that the tip is exposed in the ash melting chamber and provided below the leaving brick 4 are integrated. It is composed of a removable cartridge brick. Reference numeral 19 denotes a power source for energizing the upper electrode brick 5 and the lower electrode brick 6, and 20 and 21 are electric wires thereof (FIG. 1). Reference numeral 8 denotes a metal discharge port provided at the lower part of the furnace wall of the ash melting furnace 1. Reference numeral 9 denotes a main electrode inserted from the top of the ash melting furnace 1, and reference numeral 10 denotes a furnace bottom electrode embedded in the bottom of the ash melting furnace 1 so as to face the main electrode 7 vertically. Reference numeral 14 denotes a power source for direct current to the main electrode 9 and the bottom electrode 10, and reference numerals 15 and 16 denote electric wires thereof.
[0011]
11 is an ash solid layer such as fly ash or incinerated ash charged into the ash melting chamber 2 and floats on the molten slag layer 12 in an unmelted state. Reference numeral 13 denotes a metal layer accumulated at the bottom of the ash melting furnace 1.
[0012]
Reference numeral 17 denotes an ash inlet provided at the top of the ash melting chamber 2, in which fly ash or incinerated ash conveyed by a conveyor (not shown) is input into the ash melting chamber 2. Reference numeral 18 denotes an exhaust gas discharge port provided at the top of the ash melting chamber 2.
[0013]
Next, the operation of this embodiment will be described.
The fly ash and incineration ash charged into the ash melting chamber 2 of the ash melting furnace 1 are energized and heated to the main electrode 9 and the furnace bottom electrode 10 disposed in the ash melting chamber 2 to become molten slag 12. . The outlet 3 of the ash melting furnace 1 is provided in the middle of the furnace wall, and the molten slag 12 overflows from the outlet 3 and is continuously discharged. When the molten slag 12 comes out, unmelted ash that has floated on the molten slag 12 is prevented from flowing out by the upper electrode brick 5 having a horseshoe-shaped cross section with the lower end 5a immersed in the molten slag 12, and the inflow of outside air is prevented. Is prevented. In addition, the molten slag 12 is energized and heated at the spout 3 to the upper electrode brick 5 and the lower electrode brick 6, the viscosity is adjusted, and the flow rate is controlled. Moreover, since the spout 3 is formed by the cartridge brick which can be fitted or detached, a maintenance can be performed easily.
[0014]
The present invention is not limited to the above-described embodiment. For example, the upper electrode brick may be changed to a horseshoe shape to have a quadrangular shape, and various modifications can be made without departing from the gist of the present invention. Of course.
[0015]
【The invention's effect】
As described above, according to the present invention, the outlet of the ash melting furnace is made of cartridge bricks so that the outlet can be easily replaced, and the outflow of unmelted ash that has floated on the molten slag is prevented. In addition, the flow of outside air into the ash melting chamber is prevented, and the molten slag is heated in the vicinity of the tap outlet and discharged while controlling the flow rate of the molten slag, thus stabilizing the operation of the ash melting furnace. Excellent effects such as being able to be achieved.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an ash melting furnace according to the present invention.
FIG. 2A is an enlarged side view of a taphole, and FIG. 2B is a view taken along the line AA in FIG.
FIG. 3 is a longitudinal sectional view of a conventional electric resistance ash melting furnace.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ash melting furnace 2 Ash melting room 3 Outlet 4 Outlet brick 4a Through hole 5 Upper electrode brick 6 Lower electrode brick 7 Insulating brick 8 Metal outlet 9 Main electrode 10 Furnace electrode 11 Ash solid layer 12 Melting Slag layer 13 Metal layer 14, 19 Power source 15, 16, 20, 21 Electric wire 17 Ash inlet 18 Exhaust gas outlet

Claims (1)

An ash melting furnace that melts ash by applying direct current between the main electrode inserted from the furnace top and the furnace bottom electrode provided at the furnace bottom, and overflows the molten slag provided in the middle of the furnace wall It has a tapping outlet and a metal outlet provided in the lower part of the furnace wall. The tapping outlet surrounds the cylindrical tapping brick having a through hole in the center and the tapping brick. Insulation bricks provided in such a manner as to cover the insulation bricks from above, outflow of unmelted ash that protrudes toward the ash melting chamber and that has its lower end immersed in the molten slag and floated on the molten slag The upper electrode brick with a horseshoe-shaped cross section that is designed to prevent damage and the lower electrode brick that is embedded in the insulating brick so that the tip is exposed in the ash melting chamber, and that is provided below the laying brick It is composed of removable cartridge bricks Ash melting furnace, characterized that it is operable to pass a current between the upper electrode brick and the lower electrode brick.

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