Refractory lining combined structure of manganese-silicon submerged arc furnace

Abstract

The utility model provides a refractory lining combined structure of a manganese-silicon submerged arc furnace. The structure comprises a furnace bottom and a furnace hearth, an annular large carbon brick layer is laid on the inner wall of the furnace hearth, an impermeable layer is arranged between the furnace hearth and the annular large carbon brick layer, and lower-layer carbon bricks, middle-layer carbon bricks, upper-layer carbon bricks and a protective layer are sequentially laid on a refractory brick layer of the furnace bottom from bottom to top. The lower-layer carbon bricks, the middle-layer carbon bricks and the upper-layer carbon bricks are all formed by laying carbon bricks with grooves in the periphery in a wide-gap filler laying mode, the lower-layer carbon bricks are located between the annular large carbon brick layer and the refractory brick layer of the furnace bottom, and a compensation layer is arranged between every two adjacent layers of carbon bricks. And an elastic layer is arranged between the hearth and the external heat insulation layer. According to the utility model, the shrinkage generated after the wide-gap filler encounters a coking point in the preheating and roasting processes of the furnace lining can be compensated, and gaps caused by the shrinkage can be filled, so that the integrity of the furnace bottom of the submerged arc furnace is improved, and the expansion caused by heating of the refractory material of the furnace lining can be absorbed.

Description

Technical Field

[0001] The utility model relates to a lining structure of a submerged arc furnace, in particular to a structure of a refractory lining combination for a ferromanganese-silicon submerged arc furnace. Background Art

[0002] A submerged arc furnace, also known as an electric arc furnace or a resistance furnace, is mainly used for reducing and smelting raw materials such as ores, carbonaceous reducing agents, and solvents. When producing ferromanganese-silicon alloy, it needs to be smelted by a submerged arc furnace; during the production and smelting process of ferromanganese-silicon alloy, due to the effects of high temperature, mechanical erosion, and chemical corrosion, the furnace lining is damaged prematurely, seriously affecting the normal operation of production. The damage of the furnace lining increases energy consumption and production costs. Therefore, optimizing the furnace lining structure is an important direction for energy conservation and cost reduction of submerged arc furnaces.

[0003] The optimization process of the existing submerged arc furnace lining structure has gone through the following two stages: In the first stage, the bottom of the submerged arc furnace lining structure is laid by a three-layer carbon brick with wide joints masonry method. The specific structure is as Figure 1 shown. Above the refractory brick layer 1 at the bottom of the furnace, a lower layer carbon brick 2, a middle layer carbon brick 3, an upper layer carbon brick 4, and a protective layer 11 are laid in sequence from bottom to top. The three-layer carbon bricks are all laid by the wide joint filler 12 masonry method. An annular large carbon brick layer 5 is laid on the inner wall of the hearth 8. An anti-seepage layer 7 is provided between the refractory brick layer 1 at the bottom, the hearth 8, and the large carbon brick layer 5. Among them, the anti-seepage layer 7, the protective layer 11, and the wide joint filler 12 are made of the same material. A heat insulation layer 13 is provided between the hearth 8 and the external heat insulation layer 9. In the second stage, the masonry process of the submerged arc furnace lining structure is improved, and self-baking carbon bricks + fine joints masonry is adopted. The specific structure is as Figure 2 shown. On the refractory brick layer 1 at the bottom of the furnace, a lower layer carbon brick 2, a middle layer carbon brick 3, an upper layer carbon brick 4, and a protective layer 11 are laid in sequence from bottom to top. The three-layer carbon bricks are all laid by the fine joint masonry method. An annular large carbon brick layer 5 is laid on the inner wall of the hearth 8. An anti-seepage layer 7 is provided between the refractory brick layer 1 at the bottom, the hearth 8, and the large carbon brick layer 5. Among them, the anti-seepage layer 7 and the protective layer 11 are made of the same material. A heat insulation layer 13 is provided between the hearth 8 and the external heat insulation layer 9.

[0004] The existing two-stage furnace lining structure design has improved the tightness and overall strength of the bottom and hearth of the submerged arc furnace to a certain extent, reduced the oxidation and erosion of carbon bricks, and enhanced the ability of carbon bricks to resist mechanical erosion and chemical corrosion. However, practice has proved that these methods have not solved the problem of premature damage of the furnace lining.

[0005] Affected by the development of the steel industry, the smelting production of ferromanganese silicon alloy follows the market fluctuations and there are uncertainties in furnace shutdown. After a long-term furnace shutdown and restart, due to the rapid cooling and heating effects or uneven heat loads, the internal thermal stress of the furnace lining refractory material exceeds its structural strength and local damage occurs, resulting in the expansion and cracking of the furnace body. If the furnace is frequently started and stopped, it can be clearly observed that the furnace body steel plate cracks due to temperature changes and needs to be repaired in time. Summary of the Invention

[0006] In view of the deficiencies in the existing furnace lining structure design, the present invention provides a structure of a refractory lining combination for a ferromanganese silicon submerged arc furnace. Based on the furnace lining structure with three layers of carbon bricks and wide-gap masonry, a new furnace bottom carbon brick structure is used to build the furnace bottom structure, a compensation layer is added between the three layers of carbon bricks, and an elastic layer is added between the hearth and the insulation layer, which can improve the integrity of the furnace bottom of the submerged arc furnace and absorb the expansion caused by the heating of the furnace lining refractory material, and extend the service life of the furnace lining of the submerged arc furnace.

[0007] To solve the above technical problems, the present invention provides a structure of a refractory lining combination for a ferromanganese silicon submerged arc furnace, including a furnace bottom and a hearth. An annular large block carbon brick layer is laid on the inner wall of the hearth. The hearth and the annular large block carbon brick layer are both located above the refractory brick layer of the furnace bottom. An anti-seepage layer is provided between the hearth and the annular large block carbon brick layer. Above the refractory brick layer of the furnace bottom, a lower layer carbon brick, a middle layer carbon brick, an upper layer carbon brick and a protective layer are laid in sequence from bottom to top. The lower layer carbon brick, the middle layer carbon brick and the upper layer carbon brick are all built by the masonry method of carbon bricks with grooves on the four sides through wide-gap fillers. The lower layer carbon brick is located between the annular large block carbon brick layer and the refractory brick layer of the furnace bottom, and a compensation layer is provided between adjacent two layers of carbon bricks; an elastic layer is provided between the hearth and the external insulation layer.

[0008] A preferred technical solution of the present invention: The compensation layer, the anti-seepage layer, the protective layer and the wide-gap filler are made of the same material.

[0009] A preferred technical solution of the present invention: The annular grooves of each brick body of the lower layer carbon brick, the middle layer carbon brick and the upper layer carbon brick are opened at the position of 1 / 2 height of the brick body, the width of the annular groove is 90 - 110 mm, and the inner concave depth is 25 - 30 mm.

[0010] A preferred technical solution of the present invention: The elastic layer is made of refractory aggregate with a particle size of 3 - 15 mm.

[0011] A preferred technical solution of the present invention: The thickness of the compensation layer is 40 - 75 mm.

[0012] A preferred technical solution of the present invention: The compensation layer, the anti-seepage layer, the protective layer and the wide-gap filler are all made of electrode paste material.

[0013] Advantages of the present utility model:

[0014] (1) For the bottom of the furnace of the present utility model, carbon bricks with slots around are used instead of the original carbon bricks without slots at the bottom of the furnace, and a compensation layer is added between the three layers of carbon bricks, which can compensate for the shrinkage generated after the wide-gap filler encounters the coking point during the preheating and roasting processes of the furnace lining and fill the gaps caused by the shrinkage, thereby improving the integrity of the bottom of the submerged arc furnace.

[0015] (2) An elastic layer is provided between the hearth and the insulation layer of the present utility model to replace the insulation layer between the original hearth and the insulation layer. On the one hand, it can serve as an exhaust channel during the preheating and roasting processes of the furnace lining, preventing the accumulation of water vapor in the refractory bricks at the bottom of the furnace from causing bulging at the bottom of the furnace, and can also absorb the expansion caused by the heating of the refractory materials of the furnace lining. Description of the drawings

[0016] Figure 1 It is a schematic diagram of the furnace lining structure of a submerged arc furnace with wide-gap masonry in the prior art;

[0017] Figure 2 It is a schematic diagram of the furnace lining structure of a submerged arc furnace with narrow-gap masonry in the prior art;

[0018] Figure 3 It is a schematic diagram of the structure of the present utility model;

[0019] Figure 4 It is a front view of the carbon brick in the present utility model;

[0020] Figure 5 It is a cross-sectional view of the carbon brick in the present utility model.

[0021] In the figure: 1 - refractory brick layer, 2 - lower carbon brick, 3 - middle carbon brick, 4 - upper carbon brick, 5 - annular large carbon brick layer, 6 - compensation layer, 7 - anti-seepage layer, 8 - hearth, 9 - insulation layer, 10 - elastic layer, 11 - protective layer, 12 - wide-gap filler 13 - insulation layer, 14 - annular groove. Specific implementation manners

[0022] The present utility model will be further described below in conjunction with the drawings and embodiments. The attached Figures 1 to 5 All are the drawings of the embodiments, which are drawn in a simplified manner and are only used to clearly and concisely illustrate the purpose of the embodiments of the present utility model. The technical solutions shown in the following drawings are the specific solutions of the embodiments of the present utility model and are not intended to limit the scope of the present utility model to be protected. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present utility model.

[0023] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", "outer", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present utility model is customarily placed during use, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model. In addition, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present utility model, it should also be noted that unless otherwise clearly specified and defined, terms such as "arrangement", "connection", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0025] The embodiment provides a combined structure of refractory lining for a manganese-silicon submerged-arc furnace, as Figure 3 shown, which includes a furnace bottom and a hearth 8. An annular large block carbon brick layer 5 is laid on the inner wall of the hearth 8. Both the hearth 8 and the annular large block carbon brick layer 5 are located above the refractory brick layer 1 of the furnace bottom. An anti-seepage layer 7 is provided between the hearth 8 and the annular large block carbon brick layer 5. Above the refractory brick layer 1 of the furnace bottom, a lower layer carbon brick 2, a middle layer carbon brick 3, an upper layer carbon brick 4, and a protective layer 11 are laid in sequence from bottom to top. The lower layer carbon brick 2, the middle layer carbon brick 3, and the upper layer carbon brick 4 are all constructed by the masonry method of carbon bricks with grooves on all sides through wide joint fillers 12. The lower layer carbon brick 2 is located between the annular large block carbon brick layer 5 and the refractory brick layer 1 of the furnace bottom, and a compensation layer 6 is provided between adjacent two layers of carbon bricks. The thickness of the compensation layer is 40 - 75 mm. By adding a compensation layer between the three layers of carbon bricks, the shrinkage generated after the wide joint filler encounters the coking point during the preheating and roasting process of the furnace lining and the gaps caused by filling the shrinkage can be compensated, thereby improving the integrity of the furnace bottom of the submerged-arc furnace. An elastic layer 10 is provided between the hearth 8 and the external heat insulation layer 9. The elastic layer 10 is made of refractory aggregate with a particle size of 3 - 15 mm. Using the elastic layer 10 to replace the heat insulation layer between the original hearth and the heat insulation layer, on the one hand, it can serve as an exhaust channel during the preheating and roasting process of the furnace lining to prevent the accumulation of water vapor in the furnace bottom refractory bricks from causing the furnace bottom to bulge, and it can also absorb the expansion caused by the heating of the furnace lining refractory material.

[0026] The embodiment provides a combined structure of refractory lining for a ferromanganese-silicon submerged arc furnace. The compensation layer 6, the anti-seepage layer 7, the protective layer 11, and the wide joint filler 12 are all made of electrode paste material. As Figure 3 and Figure 4 shown, the annular grooves 14 of each brick body of the lower layer carbon bricks 2, the middle layer carbon bricks 3, and the upper layer carbon bricks 4 are opened at the position of half of the height of the carbon brick body. The width of the annular groove 14 is 90 - 110 mm, and the concave depth is 25 - 30 mm.

[0027] For the combined structure of refractory lining for a ferromanganese-silicon submerged arc furnace in the embodiment, the specific masonry process is as follows:

[0028] (1) Masonry of the furnace bottom refractory brick layer 1. The furnace bottom refractory brick layer 1 includes 4 layers of fireclay bricks and 5 layers of high-alumina bricks. All the fireclay bricks and high-alumina bricks fully paved on the furnace bottom are masonry in a herringbone structure, with a 30° intersection between the upper and lower layers, dry masonry, and the brick joints are filled with dry powder of fireclay refractory mortar and high-alumina refractory mortar respectively; the flatness of each layer is checked with a straightedge and a construction level. The gap (elastic layer) between the furnace bottom refractory brick layer 1 and the insulation layer is filled with refractory aggregate, and it is filled once every 2 - 3 layers of masonry. It is tamped with an iron rod with a diameter of Φ10 - 15 mm and a length of 1 m to ensure that the refractory aggregate is fully filled.

[0029] (2) Masonry of the furnace bottom carbon bricks. The furnace bottom carbon bricks include the lower layer carbon bricks 2, the middle layer carbon bricks 3, and the upper layer carbon bricks 4; during masonry, first, lay out the lines. The center lines of the furnace bottom masonry are staggered at 30°, and are angled clockwise or counterclockwise in the same direction to ensure that the brick joints of each layer of carbon bricks are staggered, and the tapping hole bricks in the upper layer of furnace bottom carbon bricks are aligned with the tapping hole; then, lay the furnace bottom carbon bricks full of the masonry position according to the drawing, and the bricks are arranged at an interval of 50 mm (see the drawing for special positions), and a wooden wedge with a thickness of 50 mm is placed between the carbon bricks; a 60-mm-thick furnace building paste compensation layer is laid between the lower layer and the middle layer carbon bricks and between the middle layer and the upper layer carbon bricks. The adjacent two rows of carbon bricks are staggered during masonry, and the centers of the carbon bricks in different upper and lower layers are staggered at 30° during masonry; for the construction of the wide joints between the carbon bricks, the prepared (the frying temperature of the material is 100℃ - 120℃) furnace building paste (electrode paste) is filled into the wide joints between the carbon bricks, and it is tamped firmly as it is filled; the wooden wedges shall not be removed at the parts where the furnace building paste has not been filled and tamped, and the filling and tamping work is carried out sequentially from one side of the furnace hearth to the other side.

[0030] (3) Laying of the annular large carbon brick layer 5 in the hearth: First, on the upper surface of the bottom-layer carbon bricks 2 in the furnace bottom, the inner edge line is released according to the inner radius of the annular large carbon bricks laid in a ring. Then, the annular large carbon brick layer is laid according to the brick numbers on the drawing. The annular large carbon bricks are laid with special electrode paste for furnace building (fine joint paste) between them. The annular large carbon bricks should be laid starting from both sides of the two tapping holes during laying. The refractory bricks in the hearth and the annular large carbon bricks are wedged tightly with reverse and forward wooden wedges, and jacked tightly at the closing brick position. Check whether the vertical joints of the masonry meet the requirements. After the laying of the annular large carbon brick layer 5 is completed, the gap between the annular large carbon brick layer 5 and the hearth refractory bricks is filled and tamped with furnace building paste (electrode paste) to form the anti-seepage layer 7, and at the same time, the wooden wedges are removed. When laying the annular large carbon brick layer in the hearth, the sundries and dust on the surface of the carbon bricks should be cleaned up before use. It is strictly prohibited for carbonaceous materials to contact the furnace shell. After laying the annular large carbon brick layer 5, the middle-layer furnace bottom carbon bricks and the upper-layer furnace bottom carbon bricks are laid.

[0031] (4) Laying of high-alumina bricks and fireclay bricks in the furnace wall. The high-alumina bricks in the hearth are wet-laid with high-alumina refractory mortar, and the fireclay bricks are wet-laid with fireclay refractory mortar. The gaps between the high-alumina bricks, fireclay bricks and the insulation layer in the hearth are filled with refractory granules to form the elastic layer 10. It is filled once every 2 - 3 layers of laying, and tamped with an iron rod with a diameter of Φ10 - 15mm and a length of 1m to ensure that the refractory granules are filled fully.

[0032] (5) Laying of the furnace bottom protective layer. The upper surface of the upper-layer carbon bricks 4 in the furnace bottom is cast with furnace building paste to serve as the furnace bottom protective layer 11.

[0033] As described above, it is only one embodiment of the present utility model, and its description is relatively specific and detailed. However, it should not be construed as a limitation to the scope of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several deformations and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the appended claims.

Claims

1. A refractory lining composite structure of a manganese silicon ore furnace, comprising a furnace bottom and a furnace hearth (8), an annular large carbon brick layer (5) is laid on the inner wall of the furnace hearth (8), the furnace hearth (8) and the annular large carbon brick layer (5) are both located above the refractory brick layer (1) of the furnace bottom, an impermeable layer (7) is provided between the furnace hearth (8) and the annular large carbon brick layer (5), characterized in that: A lower layer of carbon bricks (2), a middle layer of carbon bricks (3), an upper layer of carbon bricks (4) and a protective layer (11) are sequentially laid from bottom to top on the refractory brick layer (1) at the furnace bottom. The lower layer of carbon bricks (2), the middle layer of carbon bricks (3) and the upper layer of carbon bricks (4) are all built by laying carbon bricks with annular grooves through wide-slit fillers (12). The lower layer of carbon bricks (2) is located between the annular large carbon brick layer (5) and the refractory brick layer (1) at the furnace bottom, and a compensation layer (6) is provided between two adjacent layers of carbon bricks. An elastic layer (10) is provided between the furnace cylinder (8) and an external heat insulating layer (9).

2. The refractory lining composite structure of a manganese silicon ore furnace according to claim 1, characterized in that: The compensation layer (6), the anti-seepage layer (7), the protective layer (11) and the wide-slit filler (12) are made of the same material.

3. A refractory lining composite structure of a manganese silicon ore furnace according to claim 1 or 2, characterized in that: The annular groove (14) of each brick of the lower carbon brick (2), the middle carbon brick (3) and the upper carbon brick (4) is opened at a position of 1 / 2 of the height of the brick body, and the width of the annular groove (14) is 90-110 mm, and the inner concave depth is 25-30 mm.

4. A refractory lining composite structure for a manganese silicon ore furnace according to claim 1 or 2, characterized in that: The elastic layer (10) is made of refractory aggregate with a particle size of 3 to 15 mm.

5. A refractory lining composite structure for a manganese silicon ore furnace according to claim 1 or 2, characterized in that: The thickness of the compensation layer is 40-75 mm.

6. The refractory lining composite structure of a manganese silicon ore furnace according to claim 2, characterized in that: The compensation layer (6), the anti-seepage layer (7), the protective layer (11) and the wide-slit filler (12) are all made of electrode paste material.

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