JP3310874B2 - Melting furnace - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a melting furnace applied to volume reduction and detoxification of incinerated ash of refuse.

[0002]

2. Description of the Related Art In recent years, the need for ash melting furnaces has been increasing in order to reduce the volume and harmless ash remaining after incineration of refuse. In order to melt the ash in the ash melting furnace, it is necessary to set the temperature to about 1500 ° C., and the melted ash slag does not flow like ordinary fluid such as water because of the high temperature and high viscosity.

[0003] In the conventional ash melting furnace, in order to ensure the fluidity of the molten ash slag, a method of keeping the slag outlet and the slag gutter at a high temperature is adopted in most cases. There is an invention disclosed in Kaihei 6-300234. This is because if the temperature is increased, the viscosity of the slag decreases and the slag flows more easily.

[0004] Maintaining the high temperature state of the slag port and the slag gutter is generally performed by installing a burner or a heater as an auxiliary device near the slag port and the slag gutter and controlling them. However, since there is a problem that the apparatus becomes complicated, in the above-mentioned invention, a method of keeping the slag outlet and the slag gutter warm with exhaust gas is adopted.

[0005] In this exhaust gas heat retention type melting furnace,
As shown in FIG. 3A, the molten slag 7 overflows from the furnace 11, passes through the slag port 01, and slags through the slag gutter 02. Further, the exhaust gas 8 is extracted from the slag port 01 in order to increase the temperature of the slag port to facilitate the slag removal of the molten slag 7.

The cross section of the slag port 01 and the slag gutter 02 has a U-shape as shown in FIG. 3 (b). A block 4 is provided, and cooling water is caused to flow inside the copper block 4 to cool the slag gutter 02. The cooling start position is immediately after the inner surface of the furnace.

[0007] The slag gutter 02 is cooled in order to increase the durability of the slag gutter 02 by forming a slag protection layer on the surface of the slag gutter and flowing the molten slag 7 thereon. It is.

[0008]

In the conventional melting furnace, the cross-sectional shapes of the slag port and the slag gutter are U-shaped as described above. equal. For this reason, if the passage cross section is narrow, the molten slag is liable to leach out, but the slag opening is blocked by the adhesion of dust, carryover ash, and low-boiling substances. Conversely, if the passage cross section is wide, adhesion of carryover ash and the like is suppressed, but there is a problem that the molten slag meanders, cools and solidifies, and slag stops.

In addition, since the vicinity of the slag outlet is cooled by the cooling water flowing in the copper block, there is a problem that if the cooling is too strong, the vicinity of the slag outlet is closed by cooling and solidification of the molten slag. In addition, since the side surface of the slag gutter is also cooled, there is a problem in that carry-over ash and low-boiling substances adhere and become blocked.

[0010] Furthermore, since the slag gutter angle was gentle,
There was also a problem that the molten slag was cooled and solidified on the way.
The present invention seeks to solve the above problems.

[0011]

SUMMARY OF THE INVENTION A melting furnace according to the present invention is a melting furnace provided with a slag port and a slag gutter for melting molten slag obtained by melting incineration ash. The outside of the castable and the outer surface of the castable and the castable, in which the slag port for discharging slag from the inside to the outside, and the bottom surface on the inlet side made substantially flush with the lower end surface of the slag port are lowered toward the outside at an inclination angle of 5 ° or more. Surround and separate from the vicinity of the slag outlet.
A slag gutter made of a copper plate having a cooling water passage formed only below the placed outer peripheral surface , and the cross section of the slag port and the slag gutter is directed from the upper surface to the lower surface through which the molten slag flows. And heat
The flux is narrowed down to a channel width capable of concentrating about 1.5 to 2.0 times, and the contact area between the slag port and the slag and the molten slag is reduced, It is intended to prevent the molten slag that is discharged from falling below the solidification temperature.

In the above, tapping port and Dekasutoi is the width dimension of the lower part, 1.5 a heat flux than the width of the upper
Because the cross-sectional shape is narrowed down to a channel width that can be concentrated to about 2.0 times, the width of the portion where the molten slag flows is narrow, and the molten slag does not meander unlike the conventional device. substantial slag passing distance becomes short, it becomes easy to tapping of molten slag.

Further, since it was transverse sectional shape narrowed width dimension of the lower portion of the tapping port and Dekasutoi, because the smaller the heat transfer area for absorbing the heat of the molten slag, molten as compared with the conventional apparatus The temperature inside the slag is kept high, the viscosity of the molten slag is kept low , and the slag
The fact that the angle of inclination was larger than 5 °
The flow velocity is faster and the molten slag is not solidified,
Can be littered. Also, the slag port is made of brick
In addition, a cooling water passage is provided in the slag gutter near the slag outlet.
Temperature of the molten slag near the slag outlet was kept high
That the slag port is closed by solidification of the molten slag.
Without further downwardly outside circumferential surface of the tapping trough off the tapping port
Than providing the coolant passage, the high temperature in the outer side above the tapping trough
The inner circumference of the outer wall where the state is maintained and the exhaust gas from the tail gutter passes
Carry-over ash and low-boiling substances can be prevented from adhering to the upper side
While the molten slag flows under the inner peripheral side of the outer wall.
Has a slag protective layer formed on the surface of the drain gutter,
Can be enhanced.

[0014] Therefore, the molten slag tapping from tapping port becomes large shear rate, flow high flow rate the tapping port and tapping the gutter, leaving solidified therein as in the conventional apparatus
Without closing the slag port and the slag gutter, the slag can be discharged more easily than the slag gutter and the durability of the slag gutter can be improved.
Can be enhanced.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A melting furnace according to an embodiment of the present invention will be described with reference to FIG. In the melting furnace according to the present embodiment shown in FIG. 1, the sectional shape of the slag port 1 and the slag gutter 2 is a home base shape with the lower pointed end cut off, and the slag port 1 is formed by a brick 5. Formed and slag gutter 2
The inner surface is formed by the castable 3, the copper plate 9 is provided outside the castable 3, the cooling water passage 10 is provided outside the inclined portion and the bottom except the vicinity of the slag port of the copper plate 9, and the molten slag 7 is provided. Are arranged with an inclination of 17 ° in the flow direction.

In the above, since the bottom surface of the slag gutter 2 is narrow, the molten slag 7 does not meander as in the conventional apparatus, and the actual slag passage distance is shortened.
The slag is easily removed.

Further, since the heat transfer area of the slag gutter 2 at the portion where the molten slag 7 passes is reduced, the surface temperature of the castable 3 is increased, the viscosity of the molten slag 7 is reduced, and
Is increased from the conventional angle of 5 ° to 17 °, the molten slag 7 does not solidify and the slag is easily discharged.

The slag port 1 is formed of a brick 5 having heat resistance, and the slag chute 2 near the slag port is not provided with the cooling water passage 10, so that the temperature near the slag port is high. The molten slag 7 is kept and easily passes through the slag port 1.

Further, since the cooling water passage 10 is not provided outside the copper plate 9 on the side surface of the slag gutter 2 through which the exhaust gas 8 passes, this portion is kept at a high temperature, and carry-over ash to this portion is maintained. And adhesion of low-boiling substances can be prevented.

With respect to the slag port 1 and the slag gutter 2 according to the present embodiment, a test was performed to confirm the performance thereof. It was confirmed that slag could be removed even under low temperature conditions (solid slag temperature is low) at which slag solidifies and closes.

Further, the slag load of the present embodiment is 30% smaller than that of the conventional U-shaped one,
The molten slag 7 could be easily discharged. With respect to the heat flow rate, in the present embodiment, 1.5 to 2 times more concentration on the bottom of the slag gutter 2 than in the conventional one, the temperature of the castable surface is high, and the slag Had become easier.

In the present embodiment, the cross section of the slag port 1 and the slag gutter 2 has a home base shape. However, FIGS. 2 (a), (b), (c), and (d) show the respective cross sections. As shown in the figure, any shape can be used as long as the width of the lower portion can be reduced, such as a V shape, a U shape, a stepped shape, a semicircular shape, an elliptical shape, and a parabolic shape.

[0023]

Effect of the Invention melting furnace of the present invention, the shapes of the horizontal cross section width of the bottom have been narrowed down in tapping port and Dekasutoi for tapping the molten slag was increased inclination angle of the Dekasutoi As a result, the molten slag flowing inside the slag does not meander, the passing distance is shortened, and the heat transfer area is small.
Since it is kept at a very high temperature and the viscosity is kept at a low level, it does not solidify inside the slag port and the sluice gutter as in the conventional apparatus, and the slag can be easily slagged from the melting furnace. It becomes possible. In addition, the cooling water channel should be
Is provided below the outer peripheral surface of the drainage gutter.
Of closure by solidification of molten slag and inner circumference of slag gutter
Prevents carryover ash and low-boiling substances from adhering above the surface
And a slag protective layer is formed below the inner peripheral surface of the slag gutter.
Thus, the durability of the slag gutter can be improved.

[Brief description of the drawings]

1A and 1B are explanatory views of a melting furnace according to an embodiment of the present invention, wherein FIG. 1A is a side sectional view, and FIG. 1B is a view taken along the line AA of FIG.

FIG. 2 is an explanatory diagram of another cross-sectional shape of the tail gutter according to the embodiment.

FIG. 3 is an explanatory view of a conventional melting furnace, (a) is a side sectional view,
(B) is a BB arrow view of (a).

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 slag outlet 2 slag gutter 3 castable 5 brick 6 furnace wall castable 7 molten slag 8 exhaust gas 9 copper plate 10 cooling water passage 11 inside furnace

Continued on the front page (72) Inventor Masao Takuma 1-8-1 Koura, Kanazawa-ku, Yokohama-shi Yokohama Research Institute, Ltd. (72) Inventor Shizuo Yasuda 12 Nishikicho, Naka-ku, Yokohama-shi Mitsubishi Heavy Industries, Ltd. Yokohama Works (72) Inventor Yoshimasa Kawami 12 Nishiki-cho, Naka-ku, Yokohama-shi Mitsubishi Heavy Industries, Ltd. Yokohama Works (56) References JP-A-3-287890 (JP, A) JP-A-7-2729 (JP, U) 5-56, 632 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F23J 1/00 F27D 3/15

Claims (1)

(57) [Claims] 1. In a melting furnace provided with a slag port and a slag gutter for melting molten slag obtained by melting incineration ash, the slag which is formed of bricks and which discharges the molten slag from the inside of the furnace to the outside. A mouth, a castable in which the bottom surface on the inlet side made substantially flush with the lower end surface of the slag port is lowered outward at an inclination angle of 5 ° or more, and the outer peripheral surface of the castable is surrounded, and the slag is formed. and a said tapping trough consisting of a copper plate which is formed a cooling water passage only under the outer circumferential surface which is spaced from the mouth near the cross-sectional shape of the tapping opening and tapping trough from top side Toward the lower surface side where the molten slag flows , heat
The flux is narrowed down to a channel width capable of concentrating 1.5 to 2.0 times, and the contact area between the slag port and slag and the molten slag is reduced. Wherein the molten slag discharged from the slag is prevented from falling below the solidification temperature.