JPH07310910A - Electric waste melting furnace - Google Patents

Abstract

PURPOSE:To prevent an unmolten waste or a moulten slat from being mixed in an overflow slag by providing a non-water cooled refractory block for interrupting the upper layer of a molten slag in the outlet part of a molten slag exhaust port. CONSTITUTION:A molten slag exhaust port 21 is provided on the side wall of a main furnace body 11. The outlet part 21b of the molten slag exhaust port 21 forms a substantially U-shaped weir 41 made of refractory bricks and a non-water cooled refractory block 51 is provided in sliding contact with both inner wall surfaces of the recessed part of the weir 41. The non-water cooling refractory block 51 is supported by an elevation device 53 driven by a motor through a connecting member 52 which passes through a furnace cover 12. The lower surface of the block 51 is located lower than a molten slag B driven to overflow the weir 41. Accordingly, the non-water cooled refractory block 51 can interrurpt the upper layer of the molten slag B driven to overflow the weir 41. The non-water cooled refractory block 51 can be made of, for example, fused bricks of zirconium.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an electric waste melting furnace. Incinerated ash of municipal solid waste, sewage or human waste sludge or industrial waste, fly ash generated when incinerating these,
Such wastes, such as a mixture of these incinerated ash and fly ash, are melt-processed in a melting furnace to reduce the volume and render them harmless. The present invention relates to a waste melting furnace as described above, in which the waste charged into the furnace is electrically heated and melted, and the generated molten slag is overflowed from the molten slag discharge port. It concerns the improvement of the furnace.

[0002]

2. Description of the Related Art Conventionally, as an electric waste melting furnace, a furnace main body and a furnace lid attached to the furnace main body are generally provided, the furnace main body has a molten slag discharge port, and the furnace lid has waste material. An inlet and an outlet are each opened, and an electrode or a plasma torch is inserted in the furnace (Japanese Patent Laid-Open No. 60-251312). In such a conventional furnace, the waste introduced into the furnace is heated and melted by arc heating, plasma heating or resistance heating, and the generated molten slag overflows from the molten slag discharge port provided in the side wall of the furnace body to the outside of the furnace. It is to let it flow. However, in the conventional electric waste melting furnace as described above, the unmelted waste floating on the upper surface of the molten slag accompanying the molten slag flowing from the molten slag discharge port and the molten salt generated in the upper layer However, the quality of the slag recovered by crushing the molten slag that has overflowed is water cooling or air cooling, and the fact that the effective use of the slag is actually limited is limited. is there.

[0003]

The problem to be solved by the present invention is that the conventional electric waste melting furnace cannot prevent unmelted waste and molten salt from being mixed in the overflow slag. is there.

[0004]

DISCLOSURE OF THE INVENTION The present invention, however, is directed to an electric waste melting furnace in which the waste charged in the furnace is electrically heated and melted, and the generated molten slag overflows from the molten slag discharge port. A non-water-cooled refractory block that shields the upper layer of the molten slag is provided at the outlet of the molten slag discharge port.

In the present invention, the waste to be melt-processed is incinerated ash of municipal waste, sewage or human waste sludge or industrial waste, fly ash generated during incineration of these, and incinerated ash of these. And a mixture of fly ash and the like. The present invention is a melting furnace used for melting such waste, in which an electrode or a plasma torch is inserted in the furnace, and the waste put in the furnace is subjected to arc heating, plasma heating or resistance heating. The present invention relates to an electric waste melting furnace that electrically heats and melts and causes the generated molten slag to overflow from a molten slag discharge port.

The essential point in the present invention is that the outlet of the molten slag discharge port is equipped with a non-water-cooled refractory block that blocks the upper layer of the molten slag that is about to overflow from the molten slag discharge port. . The bottom surface of the non-water-cooled refractory block is located lower than the top surface of the molten slag that is about to overflow from the molten slag outlet, so the molten slag is the bottom surface of the molten slag outlet and the non-water-cooled refractory block. It is discharged from between the bottom surface of and. By installing a non-water-cooled refractory block that blocks the upper layer of molten slag that is about to overflow from the molten slag discharge port, it is generated in unmelted waste that is entrained in the molten slag and floats on its upper surface and its upper layer. This structure prevents the molten salt from being discharged.

It is conceivable to equip a water-cooled copper block in place of the non-water-cooled refractory block, but if this is done, a steam explosion will occur in the electric waste melting furnace due to the perforations caused by the sparks. There is a danger and there is a risk of electric shock due to leakage of electricity transmitted through the copper block and its support,
Further, the water-cooled copper block lowers the temperature of the molten slag and hinders the smooth discharge thereof, which is inconvenient. Even if a non-water-cooled refractory block is installed, it may be possible to install it at the inlet of the molten slag discharge port.However, in this case, the refractory block is directly exposed to the high temperature atmosphere in the furnace and This is inconvenient because the melting loss becomes large and it is difficult to replace it at high temperature.

The non-water-cooled refractory block is preferably equipped so that it can be moved up and down by driving a motor or a cylinder.
The amount of molten slag that is generated in the furnace due to the properties of the waste, the amount that is input into the furnace, and other changes in the operating conditions of the furnace, the amount of unmelted waste that floats on the upper surface, and the amount that is generated in the upper layer Since the amount of molten salt and the behavior in these furnaces fluctuate, raising and lowering the non-water-cooled refractory block according to these fluctuations promotes smooth discharge of the molten slag, and accompanies it. This is because it is possible to prevent discharge of unmelted waste and molten salt.

Further, it is preferable to equip an auxiliary electrode between the inlet and outlet of the molten slag discharge port. By heating with the auxiliary electrode, the unmelted waste floating on the upper surface of the molten slag on the upstream side of the non-water-cooled refractory block can be melted and the molten salt generated in the upper layer of the molten slag can be volatilized. This is because the molten slag whose temperature has dropped can be reheated to promote smooth discharge thereof.

[0010]

[Function] The non-water-cooled refractory block is melted because the non-water-cooled refractory block is equipped at the outlet of the molten slag discharge port by blocking the upper layer of the molten slag that is about to overflow from the melted slag discharge port. It prevents the unmelted waste floating on the upper surface of the slag and the molten salt generated in the upper layer from being discharged out of the furnace. Therefore, the quality of slag recovered from the molten slag discharged to the outside of the furnace can be improved,
It can be widely used effectively. Since it is a non-water-cooled refractory block, there is no danger of steam explosion or electric shock, and the temperature of the molten slag is not lowered carelessly so that smooth discharge thereof is not hindered. Further, since the non-water-cooled refractory block is equipped at the outlet of the molten slag discharge port and is not directly exposed to the high temperature atmosphere in the furnace, its melting loss is small and its replacement is easy.

[0011]

1 is a vertical sectional view schematically showing an embodiment of the present invention, FIG. 2 is a partially omitted lateral sectional view schematically showing the same embodiment as FIG. 1, and FIG. It is an expanded side view which shows the exit part of a molten slag discharge port about the same Example as No. 2. A furnace lid 12 is attached to the furnace body 11, a molten slag discharge port 21 is provided on the side wall 11 a of the furnace body 11, and a waste material inlet 22 and an exhaust port 23 are provided on the furnace lid 12. Main electrodes 31, 32 are inserted into the furnace through the furnace lid 21.

The outlet portion 21b of the molten slag discharge port 21 is a weir 41 made of refractory bricks formed in a substantially U shape, and is in sliding contact with both inner wall surfaces of the recess of the weir 41, and the non-water-cooled refractory block 51. Is equipped with. The non-water-cooled refractory block 51 is supported by a motor-driven lifting device 53 via a connecting member 52 penetrating the furnace lid 12, and the lower surface thereof is higher than the upper surface of the molten slag B trying to overflow the weir 41. The refractory block 51, which is at a low position and therefore not water-cooled, blocks the upper layer of the molten slag B that is about to overflow the weir 41. In this embodiment, the non-water-cooled refractory block 51 is made of zirconia-based fused-melt refractory brick.

The outlet 21b of the molten slag discharge port 21 is covered with a cover 13 attached to the furnace body 11 and the furnace lid 12, and the furnace lid 12 is penetrated between the inlet 21a and the outlet 21b. Then, the auxiliary electrodes 61 and 62 are inserted so as to face the molten slag discharge port 21. Although illustration and description are omitted, the lower half portion (the front half portion in FIG. 1) of FIG. 2 also has the same configuration as the upper half portion of the illustration and description thereof, and thus the illustrated embodiment In this case, a total of two molten slag discharge ports are provided on the side wall 11a of the furnace body 11, and non-water-cooled refractory blocks are provided at the respective outlets.

Molten metal A is generated in the lower layer and molten slag B is generated in the upper layer in the furnace.
The unmelted waste C charged into the furnace floats on the upper surface of the molten slag B, and molten salt (not shown) is generated in the upper layer of the molten slag B, but the weir 41 at the outlet 21b of the molten slag discharge port 21 is formed. The non-water-cooled refractory block 51 that blocks the upper layer of the molten slag B prevents the unmelted waste C and the molten salt from being discharged outside the furnace along with the molten slag B that is about to overflow the concave portion of This is the configuration.

FIG. 4 is an enlarged side view showing the outlet portion of the molten slag discharge port according to another embodiment of the present invention. The outlet portion of the molten slag discharge port (not shown) is a refractory brick weir 42 formed in a substantially U-shape, and the height adjustment spacers 42a made of refractory bricks are provided on both side standing portions of the weir 42. A T-shaped non-water-cooled refractory block 54 is placed, and the feet of the non-water-cooled refractory block 54 are in sliding contact with both inner wall surfaces of the recess of the weir 42.

[0016]

As is apparent from the above, according to the present invention described above, the quality of recovered slag can be improved and its effective utilization can be widely promoted, and there is no risk of steam explosion or electric shock and melting. There is an effect that the smooth discharge of the slag is not hindered, the melting loss of the non-water-cooled refractory block is small, and the replacement thereof is easy.

[Brief description of drawings]

FIG. 1 is a vertical sectional view schematically showing an embodiment of the present invention.

FIG. 2 is a partially omitted cross-sectional view schematically showing the same embodiment as FIG.

FIG. 3 is an enlarged side view showing the outlet of the molten slag discharge port for the same embodiment as in FIGS. 1 and 2.

FIG. 4 is an enlarged side view showing an outlet portion of a molten slag discharge port according to another embodiment of the present invention.

[Explanation of symbols]

11 ... Furnace body, 12 ... Furnace lid, 21 ... Molten slag discharge port, 22 ... Waste input port, 23 ... Exhaust port, 31, 32 ... Main electrode, 41, 42 ... weir, 5
1, 54 ... Non-water-cooled refractory block, 53 ... Lifting device, 61, 62 ... Auxiliary electrode

Claims (3)

[Claims] 1. An electric waste melting furnace in which a waste material charged into a furnace is electrically heated and melted, and the generated molten slag is caused to overflow from a molten slag discharge port. An electric waste melting furnace characterized by being equipped with a non-water-cooled refractory block that blocks the upper layer of slag. 2. The electric waste melting furnace according to claim 1, further comprising a non-water-cooled refractory block which is vertically movable. 3. The electric waste melting furnace according to claim 1, wherein an auxiliary electrode is provided between the inlet and the outlet of the molten slag discharge port.