JPH08159440A - Slag notch - Google Patents

Abstract

PURPOSE: To elongate the lift of refractories and permit the elongation of continuos operating time of a furnace, in the slag notch of a melting furnace for melting the ash of incineration. CONSTITUTION: A slag notch for slag, through which the molten slag 1 of a furnace for heating the ash of incineration to melt it flows out, is constituted of a copper block 4, having a cooling water tube therein, and a refractory 3 of alumina or graphite, which coats the upper surface and furnace side of the same copper block 4 and having good heat conductivity, so as to form the solid layer of slag on the upper surface of the refractory 3. On the other hand, projections are provided on the surface of the copper block 4, which is coated by the refractory 3, to improve the conduction of heat and a small- diametral part is provided at one part of the cooling water tube to prevent the generation of bubbles while the upper surface of the slag notch is slanted downward toward the flow direction of the slag so as to generate the solid layer of stabilized slag on the upper surface of the refractory 3.

Description

Detailed Description of the Invention

[0001]

[Industrial field of application] The present invention relates to a slag outlet of a furnace that heats and incinerates incineration ash discharged from a municipal solid waste incinerator, an industrial waste incinerator, etc. by heat generated by electricity or combustion of fuel, and discharges it as slag.

[0002]

2. Description of the Related Art A heat source for burning incinerator ash (including fly ash) discharged from municipal waste incinerators, industrial waste incinerators, etc. using electricity such as plasma, arc, resistance heating, etc. as a heat source and combustion of fuel In the conventional furnace that melts as, the refractory at the slag outlet part of the molten slag will be replaced every 1 to 2 weeks due to the idea that erosion is inevitable due to the slag coming out. This part was made into a brick so that it would be easy.

[0003]

The conventional slag outlet has the following problems. (1) It was necessary to stop the outflow of slag in order to replace the bricks at the outlet of the slag, and it was necessary to temporarily stop the furnace or stop the input of incineration ash. As a result, the operating rate of the furnace decreased. (2) In the work of exchanging the bricks at the outlet of the slag, the bricks heated to around 1000 ° C. by the slag that came out were to be exchanged, and the working environment was poor.

The present invention is intended to provide a slag outlet of a furnace for heating and melting incineration ash which can solve the above problems.

[0005]

The present invention has taken the following means at the outlet of slag from which the molten slag flows out of a furnace for heating and melting incinerated ash. (1) The outlet of the slag is composed of a copper block having a cooling water pipe inside and a refractory material having a high thermal conductivity and covering the upper surface of the copper block and the inside of the furnace. (2) At the outlet of the slag of (1) above, a protrusion was formed on the surface of the copper block covered with the refractory material. (3) At the outlet of the slag of (1) or (2), the cooling water pipe inside the copper block has a part that is thinned to prevent generation of bubbles. (4) At the outlet of the slag of (1), (2), or (3), the copper block is covered with a refractory made of any one of SiC, alumina-based material, and graphite-based material. (5) In the slag outlet of (1), (2), (3) or (4), the upper surface of the slag outlet is inclined downward by 0 to 10 degrees in the flow direction of the slag.

[0006]

In the present invention (1), a copper block having a cooling water pipe inside is provided, and since the upper surface of the copper block and the inside of the furnace are covered with a refractory material having a high thermal conductivity, the molten slag is touched. The surface of the slag mouth is appropriately cooled, and the slag that is slagged forms a fixed layer (hereinafter referred to as a self-coat layer) that is solidified by cooling on the slag mouth surface. The self-coating layer protects the refractory surface from the slag flowing and flowing, thus extending the life of the refractory.

In the invention (2), the invention (1)
In, the projections are formed on the surface of the copper block coated with the refractory material, and the refractory material having a high thermal conductivity is coated thereon, so that the heat transfer between the copper block and the refractory material is improved.

In the invention (3), the invention (1)
Alternatively, in (2), a part of the cooling water pipe inside the copper block is thin, and the cooling water pipe is effectively cooled by preventing bubbles from being generated.

According to the present invention (4), in the present invention (1), (2) or (3), S having good thermal conductivity.
The copper block is covered with a refractory material made of any one of iC, alumina-based material, and graphite-based material, and the surface of the outlet that contacts the molten slag is effectively cooled.

In the present invention (5), the above-mentioned present invention (1),
In (2), (3) or (4), since the upper surface of the outlet of the slag is inclined 0 to 10 degrees downward in the flow direction of the slag, the downflow speed of the molten slag becomes an appropriate magnitude, It is possible to prevent the stable self-coating layer from being formed on the upper surface of the outlet of the slag, and also to prevent the cooling solid layer of the slag from growing to block the outlet.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

This embodiment relates to a slag outlet of a graphite electrode type plasma melting furnace for melting incineration ash containing fly ash discharged from an incinerator for municipal solid waste, an incinerator for industrial waste, etc. In the furnace, a graphite electrode 6 is arranged, which is an slag 1 in which an arc 7 is generated and incinerated ash is melted. The outlet of the melting furnace is composed of a copper block 4 described below and a refractory 3 having good thermal conductivity and covered with the copper block 4.

Inside the copper block 4 having a concave vertical section, there is provided a cooling water pipe 8 having a circular section through which cooling water 5 flows.
Inside the furnace of the cooling water pipe 8, a portion 10 having a small inner diameter is provided so as to prevent generation of bubbles of cooling water. Further, a plurality of protrusions 9 are provided on the upper surface of the copper block 4 on the slag slag side and on the inside of the furnace, and the upper surface of the copper block 4 and the furnace are covered with the refractory material 3. As shown in FIG. 2, the flow path 11 of the slag slag 2 which will be described later has a concave shape.
Are formed.

As shown in FIG. 3, the upper surface of the refractory material 3 forming the upper surface of the outlet port is inclined downward by 0 to 10 degrees in the flow direction of the outlet slag 2. Further, as the refractory material 3, SiC, alumina-based or graphite-based material having good thermal conductivity is used, and a refractory material having a SiC content of 30 to 95% or a graphite content of 20 to 100% is particularly suitable. . Furthermore, as the copper block 4, the inner diameter of the water pipe is 10 mm.
It is desirable to construct a copper block having a thickness of 50 mm or more having a cooling water pipe 8 of about 50 mm, and the copper block 4 having the cooling water pipe 8 through which the cooling water 5 flows causes the refractory 3 through which the slag slag 2 flows. Surface temperature is 1200 ℃ to 1
It is set to be 000 ° C.

In the present embodiment, the incineration ash and the like charged into the furnace form the slag 1 which is melted by heating with the arc 7 generated from the graphite electrode 6 and flows in the furnace. The continuous supply of incinerated ash increases the amount of slag 1 in the furnace,
Flows out from the slag mouth through the flow path 11 of the slag slag on the upper surface of the refractory 3 due to overflow, and the slag slag 2
Becomes In this case, the surface of the refractory material 3 at the outlet of the slag that comes into contact with the slag slag 2 is likely to be eroded by the high temperature of the slag slag 2. However, since the copper block 4 through which the cooling water 5 flows in the cooling water pipe 8 is provided on the back side of the refractory material 3 at the outlet, the refractory material 3 is cooled, and the surface temperature of the refractory material 3 is 1200 ° C to 1000 ° C. Since the temperature is about ℃, the contact portion of the slag slag 2 with the refractory 3 is solidified by cooling, and the surface of the refractory 3 at the outlet is self-coated with this slag solid layer to prevent erosion of the refractory 3. Can be prevented.

A plurality of protrusions 9 are provided on the upper surface of the copper block 4 coated with the refractory material 3 and on the inside of the furnace, so that heat transfer between the copper block 4 and the refractory material 3 is improved, and the slag remains. The slag can be cooled effectively.

Further, since the cooling water pipe 8 in the copper block 4 is provided with a portion 10 having a small inner diameter inside the furnace which receives heat from the inside of the furnace, bubbles are generated in the cooling water 5 in the cooling water pipe 8. And the refractory 3 can be effectively cooled.

Slag slag 2 flowing on the upper surface of refractory 3
If the flow velocity of the slag is too fast, the slag solid layer will not be easily generated on the upper surface of the refractory material 3. If the flow velocity of the slag slag 2 is too slow, the slag solid layer will be likely to be generated, but on the other hand, the growth of the slag outlet It becomes easy to cause occlusion. In this embodiment, since the upper surface of the refractory material 3 is inclined downward by 0 to 10 degrees in the flow direction of the slag slag 2 as described above, the flow velocity of the slag slag 2 becomes an appropriate value and stable. A solid layer of slag is formed on the upper surface of the refractory 3 and the upper surface of the refractory 3 is the slag slag 2
It is more protected and its life can be extended.

In this embodiment, the inclination angle of the upper surface of the refractory material 3 is 0 to 10 degrees as described above, but it may be about 0 to 20 degrees.

[0020]

As described above, the present invention can exert the following effects. (1) The life of the refractory material forming the outlet of the slag can be extended, it is almost unnecessary to replace the brick of the outlet of the slag, and the continuous operation time of the furnace is extended.
Therefore, the melting treatment cost of the incineration ash can be significantly reduced. (2) Since the brick at the outlet of the slag does not reduce the operating rate of the furnace, there is no need for skilled work such as replacing it while the furnace is shut down (while the brick is still hot). It only became necessary to perform inspections and partial repairs at regular periodic inspections.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a slag outlet part of a melting furnace according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a sectional view taken along the line BB of FIG. 2;

[Explanation of symbols]

 1 Molten slag 2 Slag slag 3 Refractory 4 Copper block 5 Cooling water 6 Graphite electrode 7 Arc 8 Cooling water pipe 9 Copper block projections 10 Cooling water pipe inner part 11 Thinned slag flow path

Claims (5)

[Claims] 1. A copper block having a cooling water pipe inside, and heat conduction for covering the upper surface of the block and the inside of the furnace at the outlet of the slag from which the molten slag flows out of the furnace for heating and melting the incinerated ash. A slag slag outlet characterized by being made of high-quality refractory material. 2. The slag outlet according to claim 1, wherein protrusions are formed on a surface of the copper block covered with the refractory material. 3. The slag outlet according to claim 1 or 2, wherein the cooling water pipe inside the copper block has a part that is thinned so that bubbles are not generated. 4. The slag slag according to claim 1, wherein the copper block is covered with a refractory material made of any one of SiC, alumina and graphite. mouth. 5. The slag slag outlet according to claim 1, wherein the upper surface of the slag slag outlet is inclined downward by 0 to 10 degrees in the slag flow direction.