JP2546086Y2 - Waste melting furnace - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a waste melting furnace for melting various wastes such as municipal solid waste and sewage sludge and wastes such as incinerated ash.

[0002]

2. Description of the Related Art Recently, as an apparatus for melting waste of this kind, an arc furnace type melting processing furnace is used, and an arc is blown between a base metal and an electrode in the furnace. Waste heat is thermally decomposed by heat and the organic matter is gasified, and the inorganic matter is discharged as molten slag from the slag port provided on the furnace side wall to the outside of the furnace to be cooled and solidified. Natsuta According to this apparatus, there is an advantage that the heavy metal in the waste is trapped in the base metal, and the volume of the slag is greatly reduced and a solidified slag which can be easily handled is obtained.

However, in the above-described melting furnace, since the waste is continuously charged and melted, a large amount of unmelted waste flows together with the molten slag into the slag outlet, and the molten slag flows together with the molten slag. There is a problem that it flows out of the furnace in an untreated state, or the slag port is closed. Therefore, to prevent this, Japanese Patent Publication No. Hei 3-9393
As disclosed in Japanese Patent Application Laid-Open No. H10-260, a furnace having an unmelted obstacle plate fixed to a furnace body at a lower end position slightly lower than the overflow weir at the slag outlet has also been proposed.

[0004]

However, even if the above-mentioned unmelted material obstacle plate is made of a refractory material, the lower end portion is worn out in a short period of time by the molten slag when the furnace operation is continued, and the lower end overflows. It wears to a position higher than the weir or further to a position above the molten slag surface, and does not function to prevent the unmelted material from reaching the overflow weir or flowing out of the furnace.
In addition, the method of repairing the lower end of the unmelted material obstacle plate with refractory requires shutting down the furnace and discharging the contents of the furnace, which requires a long shutdown of the furnace and difficult work. It cannot be adopted at all.

[0005] This invention solves the above-mentioned conventional problems, and can prevent unmelted waste from closing the slag port or flowing out of the furnace, and can continue smooth operation for a long period of time. It is an object of the present invention to provide a waste melting furnace capable of being processed.

[0006]

The waste melting treatment furnace according to the present invention is a waste melting treatment furnace for melting waste, wherein two vertically extending vertically movable slag discharge passages are provided in a waste slag discharge passage. An auxiliary electrode is provided, and the diameter of the auxiliary electrode closer to the inside of the furnace is set to a large diameter that is equal to or more than の of the width of the slag passage, and the lower end of the large diameter auxiliary electrode is immersed in the molten slag. It is characterized by comprising a lifting drive device for driving and holding.

[0007]

In the waste melting furnace of the present invention, the large-diameter auxiliary electrode on the inner side of the furnace is held with its lower end immersed in the molten slag to melt the waste.
Between the side surface of the large-diameter auxiliary electrode and the side wall surface of the slag passage,
There is a gap of about 1/4 or less of the width of the slag passage, and the molten slag passes through this gap and the lower surface of the electrode without hindrance. Most of the waste is dammed by the large-diameter auxiliary electrode, and a large lump or a large amount of unmelted waste flows to the slag port side to block the slag port, or the unmelted state from the slag port. It is prevented from flowing out of the furnace as it is. If the lower end of the large-diameter auxiliary electrode is worn, it may be lowered downward by the lifting drive, and can be used for a long time without repair work.

[0008]

1 and 2, an embodiment of the present invention will be described. In the figure, 1 is a waste melting treatment furnace, 2 is its furnace body, 3 is a furnace lid, and 4 is a heating electrode. Numeral 5 denotes a waste charging shutter leading to a waste hopper (not shown), and numeral 6 denotes a dust collecting duct leading to a dust collecting device (not shown). Reference numeral 7 denotes a base metal such as iron stored at the bottom of the furnace body 2, reference numeral 8 denotes unmelted waste, and reference numeral 9 denotes a molten slag in which the waste is melted.

Reference numeral 11 denotes a gutter-shaped slag passage provided on a side wall portion of the furnace body 2 and communicating with the furnace body, for discharging the molten slag 9 to the outside of the furnace. A slag port 13 with 12 is formed. 14 is slag passage 1
A heat insulating cover 15 which covers the upper part of 1 and the upper part to the front of the slag port 13 is a steel tubular wall for water sealing, and has a granulating spray (not shown) provided therein. Reference numeral 21 denotes a slag granulator, which comprises a water tank 22 and a conveyor 23 for carrying out the slag.

In the middle of the slag passage 11, a slag passage 11 is provided.
Along the center line 31 (see FIG. 2) of the thick auxiliary electrode 3
2 and a small diameter auxiliary electrode 33 are juxtaposed so as to be vertically movable. The auxiliary electrode 33 near the slag port 13 is composed of a normal small-diameter electrode rod corresponding to the input electric power sufficient to prevent the solidification of the molten slag 9 in the slag. Near the furnace (close to the furnace 2)
The auxiliary electrode 32 has a diameter D that is equal to the width W of the slag passage 11.
Of a large-diameter electrode rod that is １ ／ or more. The material of the auxiliary electrode 32 may be the same as that of a normal auxiliary electrode. The auxiliary electrodes 32 and 33 are connected to a power supply source (not shown), and are driven by a known lifting drive (not shown) similar to the heating electrode 4.

In the waste melting processing apparatus 40 having the above-described structure, the waste 8 is stored in the furnace body 2 by the waste charging shutter 5.
And the waste 8 is melted by arc discharge between the heating electrode 4 and the base metal 7. As a result, a molten slag 9 mainly composed of an inorganic substance is generated. The molten slag 9 flows through the slag passage 11, overflows the overflow weir 12, falls, and is converted into granulated slag by the granulating device 21. , And are carried out by a slag carrying-out device.

At this time, the large-diameter auxiliary electrode 32 is vertically positioned and held so that its lower end is immersed in the molten slag 9 (but above the base metal 7). The determination of the vertical position is based on the slag passage 1 using an ITV (not shown) or the like.
The condition inside 1 may be monitored, and the large-diameter auxiliary electrode 32 may be raised and lowered by the lifting drive device. The immersion of the auxiliary electrode 32 in the molten slag can also be confirmed by whether the auxiliary electrode 33 is energized.

By immersing the auxiliary electrode 32 in the molten slag 9, even if the unmelted waste 8 flows in the slag passage 11 together with the molten slag 9, most of the waste has a large diameter. The auxiliary electrode 32 is used to prevent the waste 8 from blocking the slag port 13 and preventing the waste 8 from flowing out to the granulator 21. Further, even if the lower end of the auxiliary electrode 32 is worn out by a long-term furnace operation, the auxiliary electrode 32 can be reliably used for a long time without any repair work to prevent the flow of unmelted waste for a long period of time.

In order to prevent solidification of the molten slag 9 at the time of slag removal, an arc between the auxiliary electrodes 32 and 33 and the base metal 7 is made in a conventional manner.
Discharge can be performed. Large diameter auxiliary electrode 3
Even when the unmelted waste 8 reaches and accumulates in the two portions, the temperature of the molten slag 9 is raised by arc discharge by the auxiliary electrodes 32 and 33 to melt the waste 8. By accelerating or directly melting the waste 8 by heating, excessive accumulation of the waste 8 at the auxiliary electrode 32 can be prevented.

This invention is based on a direct current type melting processing furnace utilizing the Joule heat generated by a heating electrode, or a molten slag formed by an auxiliary electrode which does not have a base metal in the slag passage. The present invention can also be applied to a melting processing furnace configured to prevent solidification.

[0016]

[Effect of the invention] As described above, according to the invention,
The large-diameter auxiliary electrode provided in the slag passage can prevent unmelted waste from flowing toward the slag port, block the slag port by the waste, and prevent the waste from being discharged outside the furnace. Prevents spills and keeps smooth operation for a long time.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a waste melting treatment apparatus showing one embodiment of the present invention.

FIG. 2 is an enlarged sectional view taken along line AA of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Waste melting processing furnace, 2 ... Furnace body, 4 ... Heating electrode, 7
... Base metal, 8 ... Waste, 9 ... Molten slag, 11 ...
Slag passage, 13: Slag outlet, 31: Center line, 32: Auxiliary electrode, 33: Auxiliary electrode.

Claims (1)

(57) [Scope of request for utility model registration] In a waste melting furnace for melting waste, two vertically extending auxiliary electrodes extending vertically are provided in a slag discharge passage of molten slag, and the diameter of the auxiliary electrode near the furnace inside is reduced. A large-diameter not less than 巾 of the width of the slag passage, and a lifting drive device for driving and holding the large-diameter auxiliary electrode to a position where the lower end of the auxiliary electrode is immersed in the molten slag is provided. Waste melting furnace.