JP2012207853A - Furnace structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a furnace structure which includes a plurality of laminated refractory material layers, and in which distortion or damaging of a refractory material due to the limit of thermal expansion is hard to occur.SOLUTION: A bottom refractory material layer 10 is formed in the inner bottom of a steel shell 9 having a bottomed cylindrical shape, and a sidewall refractory material layer 20 is stacked along the inner peripheral surface of the steel shell 9 on the bottom refractory material layer 10. A graphite sheet 31 is inserted without adhesion between the upper surface of the bottom refractory material layer 10 and the bottom surface of the sidewall refractory material layer 20.

Description

  The present invention relates to a furnace body structure in which a plurality of refractory material layers are laminated.

  Furnace such as steel making furnace, iron making furnace, incineration ash melting furnace, waste melting furnace is generally refractory material formed of refractory material such as refractory brick inside the bottomed cylindrical iron skin It has a furnace structure in which a plurality of layers are stacked and adjacent refractory materials are joined with refractory mortar. Since the temperature of these furnaces is as high as several hundreds of degrees Celsius during use, each refractory material thermally expands. The refractory mortar that joins the refractory materials has the function of absorbing the thermal expansion of the refractory material, but if the thermal expansion is not sufficiently absorbed, the thermal expansion is limited by the adjacent refractory material and stress is applied. appear. As a result, the force that the adjacent refractory materials press against each other acts, and the refractory material may be warped or distorted, or may be cracked or cracked.

  Therefore, in view of the above circumstances, an object of the present invention is to provide a furnace body structure in which distortion and damage of the refractory material due to limited thermal expansion are unlikely to occur.

  In order to solve the above-described problems, the furnace structure according to the present invention is a furnace structure in which a plurality of refractory material layers are stacked, and a part of the refractory material layer is disposed between a part of the refractory material layer and an upper refractory material layer. Is a graphite sheet inserted without being bonded ".

  As the “refractory material” for forming the “refractory material layer”, refractory bricks or precast blocks that are cured and dried after previously forming an irregular refractory into a predetermined shape can be used.

  The “graphite sheet” refers to a sheet material obtained by rapidly heating graphite as an intercalation compound, gasifying an inter-layer material to widen the layer spacing, and then rolling.

  Since the refractory material layer is pressed from above due to the weight of the refractory material layer laminated on the upper stage, even if it is to thermally expand at a high temperature, its elongation is limited. On the other hand, in the present invention, since the graphite sheet is inserted without being bonded to the upper refractory material layer, the upper and lower refractory material layers are relative to each other due to the high slipperiness of the graphite sheet. It can extend in the horizontal direction (direction perpendicular to the direction in which the refractory material layers are stacked one above the other). Therefore, according to the present invention having the above configuration, since the refractory material layer easily expands in the lateral direction when thermally expanding at a high temperature, the refractory material is hardly distorted or damaged due to the limited thermal expansion. .

  The furnace structure according to the present invention has the above-described configuration, wherein “the bottom refractory material layer is formed on the inner bottom of the bottomed cylindrical iron skin and the bottom refractory material layer is formed on the bottom refractory material layer. A side wall refractory material layer is laminated along the peripheral surface, and the graphite sheet is inserted between the top surface of the bottom refractory material layer and the bottom surface of the side wall refractory material layer. '' Can do.

  Since the bottom portion refractory material layer has a larger length in the lateral direction than the side wall portion refractory material layer, the total length of the bottom refractory material layer that tends to extend in the lateral direction by thermal expansion is large. However, “a bottom refractory material layer is formed on the inner bottom of the bottomed cylindrical iron skin, and a side wall refractory material layer is formed on the bottom refractory material layer along the inner peripheral surface of the iron skin. In the “laminated” configuration, the sidewall refractory material layer is laminated on the bottom refractory material layer on the outer peripheral side of the bottom refractory material layer. Therefore, the bottom refractory material layer is pressed from above on the outer peripheral side due to the weight of the side wall refractory material layer, and it is difficult for the portion to thermally expand. As a result, the bottom part refractory material layer may thermally expand on the inner peripheral side where the side wall part refractory material layer does not exist, and may warp upward or float.

  On the other hand, in the present invention, since the graphite sheet is inserted without being bonded between the upper surface of the bottom refractory material layer and the bottom surface of the side wall refractory material layer, the bottom refractory material thermally expands at a high temperature. Even if the layer is pressed from above by the side wall portion refractory material layer, it tends to extend laterally so as to slide. Therefore, according to this invention of the said structure, the thermal expansion of the bottom part refractory material layer under high temperature can be made to go to a horizontal direction, ie, the outer peripheral side of a bottom part refractory material layer. Thereby, since the thermal expansion to the upper direction in the inner peripheral side of a bottom part refractory material layer is suppressed, the curvature and raising of a bottom part refractory material layer can be suppressed.

  In addition to the above configuration, the furnace structure according to the present invention shall be "an amorphous refractory layer filled with an amorphous refractory is formed along the outer periphery of the bottom refractory material layer". Can do.

  As described above, when the bottom refractory material layer pressed from above by the side wall refractory material layer thermally expands at a high temperature, the bottom refractory material layer extends toward the outer peripheral side due to the high slipperiness of the graphite sheet. In the present invention having the above configuration, since the amorphous refractory layer is provided along the outer periphery of the bottom refractory material layer, the thermal expansion of the bottom refractory material layer extending toward the outer peripheral side is absorbed by the irregular refractory layer. Is done. Therefore, in addition to the action of accelerating the thermal expansion in the lateral direction due to the slipperiness of the graphite sheet, the lateral expansion due to the thermal expansion is absorbed by the amorphous refractory layer, so that the distortion and damage of the bottom refractory material layer are more effective. Can be suppressed.

  As described above, as an effect of the present invention, it is possible to provide a furnace body structure in which distortion and damage of the refractory material due to restriction of thermal expansion are unlikely to occur.

It is a longitudinal cross-sectional view of a furnace provided with the furnace body structure of one Embodiment of this invention.

  Hereinafter, a furnace structure of one embodiment of the present invention and a furnace 1 including the furnace structure will be described with reference to FIG. In this embodiment, the case where the furnace body structure of the present invention is applied to a melting furnace that performs melting treatment of incinerated ash, waste, valuable metal-containing recovered material, and the like will be exemplified.

  The furnace structure of the present embodiment is a furnace structure in which a plurality of refractory material layers are stacked, and a bottom refractory material layer 10 is formed on the inner bottom of a bottomed cylindrical iron skin 9 and a bottom portion. On the refractory material layer 10, a side wall portion refractory material layer 20 is laminated along the inner peripheral surface of the iron skin 9, and between the upper surface of the bottom refractory material layer 10 and the bottom surface of the side wall refractory material layer 20. Is one in which the graphite sheet 31 is inserted without being bonded.

  If it demonstrates in detail, in this embodiment, the bottom part refractory material layer 10 and the side wall part refractory material layer 20 are formed using the refractory brick as a refractory material. The bottom part refractory material layer 10 is formed in a plurality of layers on the inner bottom of the bottomed cylindrical iron skin 9, and a plurality of side wall part refractory material layers 20 are laminated thereon. Here, the side wall part refractory material layer 20 includes a side wall part lining layer 21 provided in contact with the inner peripheral surface of the iron skin 9 and a side wall part lining layer provided inside the side wall part lining layer 21. 22 is provided. The lower side of the side wall portion backing layer 21 extends to a position lower than the uppermost surface of the bottom refractory material layer 10.

  Further, the side wall portion refractory material layer 20 includes a metal discharge refractory material layer 26 formed with a discharge port 25 for discharging molten metal and a slag discharge refractory material layer 28 formed with a discharge port 27 for discharging slag. I have. Specifically, the metal discharge refractory material layer 26 is provided on the uppermost bottom refractory material layer 10, that is, at the lowermost portion of the side wall refractory material layer 20. And as for the discharge port 25 which penetrates the refractory material layer 26 for metal discharge, one end opens to the exterior of the iron shell 9, and the other end opens into the furnace. On the other hand, the slag discharge refractory material layer 28 is provided at a position higher than the metal discharge refractory material layer 26, and one end of the discharge port 27 penetrating the slag discharge refractory material layer 28 is outside the iron skin 9. It opens and the other end opens into the furnace. Here, the metal discharge refractory material layer 26 and the slag discharge refractory material layer 28 are both the side wall portion refractory material layer 20, but in this embodiment, the metal discharge refractory material layer 26 and the slag discharge refractory material layer 20. There is no distinction between the side wall lining layer 21 and the side wall lining layer 22 in the material layer 28.

  For the refractory material constituting the bottom refractory material layer 10 and the side wall refractory material layer 20, particularly for the refractory material constituting the bottom refractory material layer 10 and the side wall lining layer 22, molten metal, High corrosion resistance against ash and molten slag is required. Therefore, as the uppermost bottom refractory material layer 10, in the case of a furnace used in a reducing atmosphere, a carbonaceous refractory material or a magnesia-carbonaceous refractory material is suitable, and in the case of a furnace used in an oxidizing atmosphere, alumina -Chromium refractory materials and magnesia-chromic refractory materials are preferred. In addition, as the side wall lining 22, a carbon refractory material or a silicon carbide refractory material is suitable for a furnace used in a reducing atmosphere, and an alumina-chromium refractory material for a furnace used in an oxidizing atmosphere. And magnesia-chromic refractory materials are preferred.

  A graphite sheet 31 is inserted between the top surface of the uppermost bottom refractory material layer 10 and the bottom surface of the lowermost side wall portion lining layer 22 without being bonded. As described above, the side wall portion refractory material layer 20 includes the metal discharge refractory material layer 26, and the metal discharge refractory material layer 26 constitutes the lowermost side wall portion refractory material layer 20. Yes. Therefore, in this portion, the graphite sheet 31 is inserted between the top surface of the uppermost bottom refractory material layer 10 and the bottom surface of the metal discharge refractory material layer 26.

  And in the other part in which the graphite sheet 31 is not inserted, the adjacent refractory material is joined by a refractory mortar (not shown). The graphite sheet 31 having a thickness of 0.05 mm to 3.0 mm can be used. However, the graphite sheet 31 supports the weight of the upper refractory material layer (side wall lining layer 22) and the bottom refractory material. A thickness of 0.5 mm to 2.0 mm is preferable, and a thickness of 0.3 mm to 1.0 mm is more preferable for the above-described effect of causing the layer 10 to slide and thermally expand. Further, a plurality of graphite sheets 31 may be stacked to have a predetermined thickness, for example, two graphite sheets having a thickness of 0.5 mm may be stacked to have a thickness of 1 mm as a whole.

  In the furnace structure of the present embodiment, in addition to the above configuration, an amorphous refractory layer 35 filled with an amorphous refractory is formed along the outer periphery of the uppermost bottom refractory material layer 10. More specifically, the amorphous refractory layer 35 is formed between the outer peripheral surface of the uppermost bottom refractory material layer 10 and the inner peripheral surface of the side wall portion backing layer 21. Here, the amorphous refractory layer 35 can be formed using an amorphous refractory such as carbon, alumina-magnesia, alumina-silica, and high alumina.

  Furthermore, the furnace 1 of the present embodiment includes a furnace lid 40, and the furnace lid 40 has a configuration in which a lid portion refractory material layer 41 is lined inside a furnace lid iron skin 49.

  When performing the melting treatment of incinerated ash, waste, valuable metal-containing recovered material, etc., using the furnace 1 having the furnace structure having the above-described configuration, the burner, the electrode, Heat with plasma. If it does so, since the inside of a furnace will become very high temperature of 1400 degreeC-1700 degreeC, a refractory material layer will thermally expand. In particular, the uppermost bottom refractory material layer 10 and the lower side of the side wall lining layer 22 that are in contact with the melted object to be processed have a high temperature and greatly expand.

  Here, the outer peripheral side in the uppermost bottom refractory material layer 10 receives the weight of the side wall lining layer 22 and the furnace lid 40 and is pressed from above. Therefore, when the uppermost bottom refractory material layer 10 and the lowermost side wall lining layer 22 are joined with a refractory mortar, the bottom refractory material layer 10 cannot thermally expand on the outer peripheral side. Therefore, the bottom refractory material layer 10 is thermally expanded toward the center of the furnace on the inner peripheral side, and is thermally expanded upward. As a result, the uppermost bottom refractory material layer 10 may warp upward or may float.

  On the other hand, in the present embodiment, the uppermost bottom refractory material layer 10 and the lowermost side wall lining layer 22 are not bonded, and a highly slidable graphite sheet 31 is inserted between them. Therefore, the uppermost bottom refractory material layer 10 tends to extend toward the outer peripheral side. The thermal expansion toward the outer peripheral side is absorbed by the amorphous refractory layer 35 provided along the outer periphery of the uppermost bottom refractory material layer 10.

  As described above, in the furnace structure of the present embodiment, the thermal expansion of the bottom refractory material layer 10 is restrained from being limited by the action of the graphite sheet 31 that directs the thermal expansion of the bottom refractory material layer 10 toward the outer peripheral side. And distortion and damage of bottom refractory material layer 10 can be controlled effectively.

  In addition, the graphite sheet 31 is excellent in heat resistance in addition to having high slipperiness, and is therefore suitable as a structure of a furnace body structure used at high temperatures. In addition, the graphite sheet 31 is flexible and rich in elasticity, so that it has excellent sealing properties and has a property of being difficult to wet with molten metal and molten slag. Thereby, even if the refractory material layers are not bonded, the presence of the graphite sheet 31 has an advantage that the molten metal and the molten slag do not easily enter the refractory material layers.

  Furthermore, in the furnace structure of the present embodiment, the bottom portion is obtained by a synergistic effect of the action of the graphite sheet 31 and the action of the amorphous refractory layer 35 absorbing the thermal expansion of the bottom refractory material layer 10 extending to the outer peripheral side. The distortion and damage of the refractory material layer 10 can be more effectively suppressed.

  The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the above-described embodiments, and various improvements can be made without departing from the scope of the present invention as described below. And design changes are possible.

  For example, although the case where the bottom part refractory material layer 10 and the side wall part refractory material layer 20 were formed with the refractory brick was illustrated above, it is not limited to this and you may use a refractory brick and a precast block together.

  The furnace structure of the present invention can also be applied to a furnace additionally provided with a configuration other than the above, such as a furnace in which an electrode is inserted through the bottom refractory material layer.

DESCRIPTION OF SYMBOLS 1 Furnace 9 Iron skin 10 Bottom part refractory material layer 20 Side wall part refractory material layer 21 Side wall part lining layer (side wall part refractory material layer)
22 Side wall lining layer (side wall refractory material layer)
26 Refractory material layer for metal discharge (side wall refractory material layer)
28 Refractory material layer for discharging slag (side wall refractory material layer)
31 Graphite sheet 35 Amorphous refractory layer

Claims (3)

A furnace structure in which a plurality of refractory material layers are laminated,
A furnace structure characterized in that a graphite sheet is inserted between a part of a refractory material layer and an upper refractory material layer without being bonded. A bottom refractory material layer is formed on the inner bottom of the bottomed cylindrical iron skin, and a side wall refractory material layer is laminated on the bottom refractory material layer along the inner peripheral surface of the iron skin. And
The furnace structure according to claim 1, wherein the graphite sheet is inserted between an upper surface of the bottom refractory material layer and a bottom surface of the sidewall refractory material layer. The furnace structure according to claim 2, wherein an amorphous refractory layer filled with an amorphous refractory is formed along an outer periphery of the bottom refractory material layer.

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