Optimized blast furnace hot blast stove bottom structure and construction method

Abstract

The present application relates to hot blast stove structure technical field, mainly disclose an optimized blast furnace hot blast stove bottom structure and construction method, blast furnace hot blast stove bottom structure includes furnace shell, apron, furnace column and profiled steel, the bottom plate of furnace shell is above the outside of the outermost circle furnace column and is arranged along the center circumference of furnace shell with steel support formwork, the outer wall of steel support formwork is filled with refractory pouring material between the inner wall of furnace shell, and is arranged with reinforcing steel bar inside refractory pouring material, the inner wall of steel support formform is filled with spray material to the center of furnace shell, the inner wall of furnace shell is sequentially provided with fibre felt and big wall brick, the refractory pouring material and spray material above the inside of big wall brick to the center of furnace shell is sequentially arranged with clay cement mortar and low creep clay brick, the material usage is effectively reduced by the above blast furnace hot blast stove bottom structure and its construction method, and the construction period is shortened, the investment cost of hot blast stove bottom position is reduced, and the original stability of structure is ensured.

Description

Technical Field

[0001] This invention relates to the field of hot blast stove structure technology, and in particular to an optimized blast furnace hot blast stove hearth structure and construction method. Background Technology

[0002] With the development of the ironmaking industry, the blast furnace hot blast stove system has formed a complete structural system. The top-fired hot blast stove technology has also matured and been widely used. In the face of the social environment where market demand is becoming saturated and market competition is becoming increasingly fierce, it is imperative to optimize and upgrade the blast furnace hot blast stove system and reduce costs and increase efficiency.

[0003] Optimizing design and construction methods is a major way to reduce costs and increase efficiency in blast furnace hot blast stove engineering construction. It plays an important guiding role in the future development of hot blast stove technology. Reducing engineering construction costs can promote the upgrading of hot blast stove technology and significantly improve the market competitiveness of hot blast stoves. The furnace bottom, as the part connected to the foundation and supporting the entire upper structure of the hot blast stove, has always been a key focus of design and construction control in terms of structural stability and preventing air leakage. Chinese invention patent CN102719584B discloses a hot blast stove with preheating combustion of regenerator body. It discloses the existing hot blast stove furnace bottom structure, with a cold air chamber below the hot blast stove regenerator and above the furnace bottom. The grate is placed in the cold air chamber, and there are support columns fixed to the furnace bottom at the bottom of the grate. The structure uses grouting material under the furnace bottom steel shell, and steel sections, reinforcing bars, support columns and their components are arranged on the furnace bottom steel shell and refractory castable is poured. For specific construction, see attached... Figure 3 As shown, the furnace bottom is a large circular plate made of steel splicing, with a diameter of approximately 7-9 meters. Depending on the design requirements, the edge of the furnace bottom has a C-shaped bend transition structure, smoothly welded to the furnace body steel structure. H200x200 steel profiles are welded to the circular plate of the furnace bottom. The steel profiles are in an irregular grid pattern. The grid holes are used to install grate support columns and fixing pillar bolts and channel steel. Reinforcing steel mesh is tied about 0.4 meters above the furnace bottom, staggered to the grate support space. Then, PN-AHS refractory is poured into the entire area below the reinforcing steel mesh. After pouring, the furnace wall is built along the edge to the furnace top. Three layers of refractory bricks are laid on the furnace bottom inside the furnace wall. There are generally about 20 grate support columns. The refractory castable for this structure is generally selected from the grade PN-AHS, and the service temperature can reach 1350℃.

[0004] The furnace bottom of the hot blast stove, as a crucial load-bearing structure on the foundation, operates under long-term conditions of alternating cold air and high-temperature flue gas, with its actual operating temperature fluctuating between 180℃ and 450℃. The load of over 1000 tons across the entire furnace body is transferred through the furnace walls to the edge of the furnace bottom, then through reinforcing steel and refractory castables to the furnace bottom plate, and finally to the foundation. The 1000-ton load of the checker bricks on the grate and furnace columns is distributed among the column bases and directly transferred to the furnace bottom plate, ultimately to the foundation. The aforementioned hot blast stove furnace bottom structure and construction method have the following problems: 1. To a certain extent, the selection of material specifications is too high, leading to material waste; 2. The existing hot blast stove furnace bottom structure has a long construction period. Summary of the Invention

[0005] The purpose of this invention is to provide an optimized blast furnace hot blast stove bottom structure and construction method to effectively reduce material usage and shorten the construction cycle, thereby reducing the investment cost of the hot blast stove bottom while ensuring the original stability of the structure.

[0006] To achieve the above objectives, the technical solution of this invention is an optimized blast furnace hot blast stove bottom structure, comprising a furnace shell, a skirt, furnace columns, and structural steel sections. Structural steel sections are arranged above the bottom plate of the furnace shell in an irregular grid pattern. Furnace columns are installed within the pores formed by the structural steel sections. A skirt is provided at the outer edge of the bottom of the furnace shell and is fixed to the foundation by bolts. Grouting material is filled below the bottom plate of the furnace shell. Steel formwork is arranged circumferentially around the center of the furnace shell, outside the outermost ring of furnace columns, above the bottom plate of the furnace shell. The outer wall of the steel formwork is flush with the furnace shell. The inner walls are filled with refractory castable, and steel bars are arranged inside the refractory castable. The inner wall of the steel formwork is filled with spray paint from the center of the furnace shell. Fiber felt and large wall bricks are arranged in sequence on the inner wall of the furnace shell. The fiber felt is tightly attached to the inner wall of the furnace shell. Large wall bricks are built from bottom to top on the inner side of the fiber felt. Clay cement mortar is arranged above the refractory castable and spray paint from the inner side of the large wall bricks to the center of the furnace shell. Low creep clay bricks are laid on the clay cement mortar. A layer of clay cement mortar is laid on the refractory castable and spray paint, and two layers of low creep clay bricks are built. Through the above technical solution, steel formwork is added, and the original refractory castable is replaced with sprayed paint between the inner side of the steel formwork and the center of the furnace shell. Compared with refractory castable, sprayed paint has better heat insulation effect and lighter weight. It can reduce the temperature of the hot blast stove bottom while reducing the overall weight of the furnace body and the foundation load. It can effectively ensure the service life of the hot blast stove bottom and reduce the hidden dangers of overheating cracking of the hot blast stove bottom foundation and thermal stress cracking and air leakage of the furnace bottom steel shell. The structural form of using sprayed paint to partially replace refractory castable has better economic benefits than the original refractory castable structure. Sprayed paint material has low cost and is easy to construct. The new structural form can significantly reduce costs. In addition, the use of sprayed paint structure can eliminate the amount of steel reinforcement in this part, saving steel and shortening the steel reinforcement laying and binding time, thus shortening the construction cycle.

[0007] A further technical solution of the present invention is that the furnace columns are evenly arranged above the bottom plate of the furnace shell and fixed with bolts.

[0008] A further technical solution of the present invention is that the height of the steel formwork is consistent with the height of the refractory castable, and the steel formwork is made of steel plate of a certain thickness.

[0009] A further technical solution of the present invention is that the height of the sprayed coating is consistent with the height of the refractory castable.

[0010] A further technical solution of the present invention is that bidirectional reinforcing bars are arranged inside the refractory castable, with the two ends of the reinforcing bars respectively connected to the inner wall of the furnace shell and the outer wall of the steel formwork.

[0011] A further technical solution of the present invention is that the height of the fiber felt and the large wall bricks is consistent with the height of the furnace shell.

[0012] An optimized construction method for the hearth structure of a blast furnace hot blast stove includes the following steps:

[0013] S1. Steel structure installation: The steel structure such as furnace shell, skirt, furnace column, and structural steel is installed in place, and is firmly fixed by welding or mechanical connection, meeting the straightness, verticality and inner diameter deviation conditions required by the design.

[0014] S2. Grouting at the bottom of the furnace: A hole is made in the bottom plate of the furnace shell and a short pipe is installed at the opening. Grouting material is applied to the bottom of the furnace through the short pipe. After grouting is completed, the short pipe is cut off and the hole is sealed.

[0015] S3. Install steel formwork: Install steel formwork between the outermost furnace column and the inner wall of the furnace shell for refractory casting. The steel formwork is perpendicular to the bottom plate of the furnace shell and arranged around the center of the furnace shell. Weld the steel formwork to the bottom plate of the furnace shell and the side wall of the structural steel.

[0016] S4. Reinforcing steel reinforcement: Two-way reinforcing steel reinforcement is laid between the furnace shell and the steel formwork. The two ends of the reinforcing steel reinforcement are welded to the inner wall of the furnace shell and the outer wall of the steel formwork, respectively, and the reinforcing steel reinforcement is tied and fixed together.

[0017] S5. Refractory castable pouring: Refractory castable is poured at the location where the steel reinforcement is laid between the furnace shell and the steel formwork, and the pouring height meets the design requirements;

[0018] S6. Spray coating construction: Lightweight spray coating is used to fill the space between the furnace center and the steel formwork, and the filling height is consistent with the height of the refractory castable.

[0019] S7. Leveling the furnace bottom and laying wall bricks: After the refractory castable and spray coating at the bottom of the furnace shell are completed, and the structure is stabilized, the bottom of the furnace shell is leveled, and the construction of large wall bricks and fiber felt is carried out. Fiber felt is laid on the inner wall of the furnace shell, and large wall bricks are laid on the inside of the fiber felt. The height of the fiber felt and large wall bricks is the same as that of the furnace shell.

[0020] S8. Construction of clay bricks at the furnace bottom: In S7, when the construction height of the large wall bricks is greater than the design height of the low creep clay bricks at the furnace bottom, clay cement mortar is laid on top of the refractory castable and spray coating, and then two layers of low creep clay bricks are laid.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] Based on the actual working conditions and load distribution of the furnace bottom, this application optimizes the original hot blast stove's all-refractory castable structure. It adopts a structure combining refractory castable with reinforcing steel bars and spray coating. Firstly, this optimized furnace bottom structure reduces the use of reinforcing steel bars, requiring only their application near the furnace pillars at the furnace bottom edge, without affecting their function of transferring furnace wall loads to the furnace bottom. This avoids the difficulty of extensive steel bar binding, significantly reducing construction time and shortening the construction period. Secondly, the amount of steel bars used is greatly reduced, lowering the cost of steel materials and avoiding material waste. Furthermore, the use of refractory castable is also significantly reduced; the optimized furnace bottom structure uses less refractory castable, and the areas using lightweight spray coating have a lower bulk density, resulting in a significant reduction in the overall weight of the furnace bottom refractory castable and spray coating. Combined with the price difference between refractory castable and spray coating, this further reduces the investment cost of the furnace bottom. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the blast furnace hot blast stove bottom structure in a specific embodiment of the present invention.

[0025] Figure 2 This is a partial sectional view of the bottom structure of the blast furnace hot blast stove in a specific embodiment of the present invention.

[0026] Figure 3 This is a partial cross-sectional view of the bottom structure of a blast furnace hot blast stove in the prior art.

[0027] In the diagram: 1. Furnace shell; 2. Skirt support; 3. Furnace column; 4. Section steel; 5. Grouting material; 6. Steel formwork; 7. Reinforcing steel; 8. Refractory castable; 9. Spray paint; 10. Large wall brick; 11. Fiber felt; 12. Clay cement mortar; 13. Low creep clay brick. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1

[0030] like Figures 1-2 As shown, an optimized blast furnace hot blast stove bottom structure includes a furnace shell 1, a skirt 2, furnace columns 3, and structural steel 4. Structural steel 4 is provided above the bottom plate of the furnace shell 1. The structural steel 4 is arranged in an irregular grid pattern. Furnace columns 3 are provided in the pores formed by the structural steel 4. The furnace columns 3 are evenly arranged above the bottom plate of the furnace shell 1 and fixed with bolts. A skirt 2 is provided at the bottom outer edge of the furnace shell 1, and the skirt 2 is fixed to the foundation by bolts. Grouting material 5 is filled below the bottom plate of the furnace shell 1. Above the bottom plate of the furnace shell 1, steel formwork 6 is arranged around the center circumference of the furnace shell 1 outside the outermost furnace column 3. The steel formwork 6 is made of steel plate of a certain thickness. Refractory castable 8 is filled between the outer wall of the steel formwork 6 and the inner wall of the furnace shell 1. The height of the steel formwork 6 is the same as the height of the refractory castable 8, and steel bars 7 are arranged inside the refractory castable 8. The bidirectional steel bars 7 are arranged inside the refractory castable 8, and the two ends of the steel bars 7 are respectively connected to the inner wall of the furnace shell 1 and the outer wall of the steel formwork 6. The inner wall of the steel formwork 6 to the center of the furnace shell 1 is filled with spray paint 9, and the height of the spray paint 9 is the same as the height of the refractory castable 8. Fiber felt 11 and large wall bricks 10 are sequentially arranged on the inner wall of the furnace shell 1. The fiber felt 11 is tightly attached to the inner wall of the furnace shell 1. Large wall bricks 10 are built from bottom to top on the inner side of the fiber felt 11. Clay cement mortar 12 is laid on the inner side of the large wall bricks 10 to the center of the furnace shell 1 above the refractory castable 8 and spray coating 9. Low creep clay bricks 13 are laid on the clay cement mortar 12. A layer of clay cement mortar 12 is laid on top of the refractory castable and spray coating 9, and two layers of low creep clay bricks 13 are built. The height of the fiber felt 11 and the large wall bricks 10 is the same as the height of the furnace shell 1.

[0031] Through the above technical solution, a steel formwork 6 is added, and the original refractory castable 8 is replaced with sprayed paint 9 between the inner side of the steel formwork 6 and the center of the furnace shell 1. Compared with refractory castable, sprayed paint 9 has better heat insulation effect and lighter weight. It can reduce the temperature of the hot blast stove bottom while reducing the total weight of the furnace body and the foundation load. It can effectively ensure the service life of the hot blast stove bottom and reduce the hidden dangers of overheating cracking of the hot blast stove bottom foundation and thermal stress cracking and air leakage of the furnace bottom steel shell. The structural form of using sprayed paint 9 to partially replace refractory castable has better economic benefits than the original refractory castable structure. Sprayed paint 9 has low material cost and is easy to construct. The new structural form can significantly reduce costs. In addition, the structural form of sprayed paint 9 can eliminate the amount of steel reinforcement 7 to be laid in this part, saving steel and shortening the laying and binding time of steel reinforcement 7, thus shortening the construction cycle.

[0032] An optimized construction method for the hearth structure of a blast furnace hot blast stove includes the following steps:

[0033] S1. Steel structure installation: The steel structure, including furnace shell 1, skirt 2, furnace column 3, and steel section 4, is installed in place, and is firmly fixed by welding or mechanical connection, meeting the straightness, verticality, and inner diameter deviation requirements of the design.

[0034] S2. Grouting at the bottom of the furnace: A hole is made in the bottom plate of the furnace shell 1 and a short pipe is installed at the opening position. Grouting material 5 is applied to the bottom of the furnace through the short pipe. After grouting is completed, the short pipe is cut off and the hole is sealed.

[0035] S3. Install steel formwork 6: Install steel formwork 6 between the outermost furnace column 3 and the inner wall of the furnace shell 1 for refractory casting. The steel formwork 6 is perpendicular to the bottom plate of the furnace shell 1 and arranged around the center of the furnace shell 1. Weld the steel formwork 6 to the bottom plate of the furnace shell 1 and the side wall of the steel section 4.

[0036] S4. Laying out reinforcing bars 7: Laying out bidirectional reinforcing bars 7 between the furnace shell 1 and the steel formwork 6. The two ends of the reinforcing bars 7 are welded to the inner wall of the furnace shell 1 and the outer wall of the steel formwork 6, respectively, and the reinforcing bars 7 are tied and fixed together.

[0037] S5. Refractory castable pouring: Refractory castable is poured at the position where the steel reinforcement 7 is arranged between the furnace shell 1 and the steel formwork 6, and the pouring height meets the design requirements.

[0038] S6. Construction of spray coating 9: Lightweight spray coating 9 is used to fill the space between the furnace center and the steel formwork 6, and the filling height is consistent with the height of the refractory castable.

[0039] S7. Leveling the furnace bottom and laying wall bricks: After the refractory castable and spray coating 9 at the bottom of the furnace shell 1 are completed, and the structure is stabilized, the bottom of the furnace shell 1 is leveled, and the large wall bricks 10 and fiber felt 11 are constructed. Fiber felt 11 is laid on the inner wall of the furnace shell 1, and large wall bricks 10 are laid on the inner side of the fiber felt 11. The height of the fiber felt 11 and the large wall bricks 10 is the same as that of the furnace shell 1.

[0040] S8. Construction of clay bricks at the furnace bottom: In S7, when the construction height of the large wall bricks 10 is greater than the design height of the low creep clay bricks 13 at the furnace bottom, clay cement mortar 12 is laid on top of the refractory castable 8 and the spray coating 9, and then two layers of low creep clay bricks 13 are laid.

[0041] Based on the hot blast stove bottom structure scheme in Embodiment 1, the construction method in this embodiment can reduce the use of reinforcing steel bars 7 at the bottom of the furnace shell 1. They only need to be laid up to the vicinity of the furnace column 3 at the bottom edge of the furnace shell 1, without affecting its function of transferring the load from the furnace wall to the furnace bottom. This avoids the difficulty and large quantity of steel bars 7 required for extensive binding work, and the binding can be completed in just one working day. In contrast, in the prior art, fully laying reinforcing steel bars 7 at the bottom of the furnace shell 1 requires at least three working days.

[0042] The use of steel reinforcement 7 is greatly reduced, requiring only 0.6 tons of steel reinforcement 7, thus lowering material costs and avoiding material waste. In contrast, the existing technology requires 4 tons of steel reinforcement 7 to fully cover the entire furnace bottom.

[0043] The use of refractory castables is also greatly reduced. The optimized furnace bottom structure uses only 10 tons of refractory castable 8, while the area using lightweight spray coating 9 has a lower bulk density. The total weight of the refractory castable and spray coating 9 used in the entire furnace bottom is only 30 tons, which is half the weight. Combined with the price difference between refractory castable 8 and spray coating 9, the investment cost of the furnace bottom can be further reduced.

[0044] Since the center of the furnace bottom only withstands temperatures below 450°C and has a relatively small load-bearing capacity, it is covered only by two layers of staggered low-creep clay bricks 13. Therefore, when considering the selection of the refractory spray coating 9 at the bottom center of the furnace shell 1, there is still considerable room for exploration in terms of material properties. In engineering examples, some of the rebound material of the spray coating 9 can be reused to further reduce investment costs and reduce waste emissions.

[0045] Specific example

[0046] In this specific example, the steel formwork 6 is made of 10mm thick steel plate, and the structure formed by the steel formwork 6 is circular in cross-section; the reinforcing steel 7 is made of round steel with a diameter of 16mm. The engineering characteristics of the optimized and unoptimized hot blast stove hearth structure are shown in Table 1 after calculation.

[0047]

[0048] Table 1. Comparison of Engineering Characteristics Before and After Optimization

[0049] As can be seen from the above, the optimized and improved furnace bottom structure of this application can reduce the investment of a single hot blast stove by approximately 180,000 yuan. Based on experience, the production process of a typical hot blast stove generally requires the construction of more than three stoves to meet the usage requirements. Therefore, this application can save at least 530,000 yuan in investment costs in the construction of blast furnace hot blast stoves. Furthermore, the service life of the furnace bottom is significantly improved.

[0050] An optimized hot blast stove bottom structure according to an embodiment of this application first analyzes the working conditions and load transfer of the bottom of the stove to confirm the path of the load on the stove body and the load on the checker bricks to the roadbed. By adopting an optimized structure, the use of reinforcing steel bars 7 and refractory castable 8 is reasonably reduced, thereby reducing the construction difficulty and construction period, reducing the investment cost of the hot blast stove, and making reasonable use of construction waste, reducing waste emissions and pollution.

[0051] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. An optimized blast furnace hot blast stove bottom structure, comprising a furnace shell (1), a skirt (2), furnace columns (3), and structural steel (4), wherein structural steel (4) is provided above the bottom plate of the furnace shell (1), the structural steel (4) is arranged in a grid pattern, furnace columns (3) are provided in the diaphragms formed by the structural steel (4), a skirt (2) is provided at the bottom outer edge of the furnace shell (1), and grouting material (5) is filled below the bottom plate of the furnace shell (1); characterized in that: Above the bottom plate of the furnace shell (1), a steel formwork (6) is arranged around the furnace shell (1) on the outer side of the outermost furnace column (3). The outer wall of the steel formwork (6) and the inner wall of the furnace shell (1) are filled with refractory castable (8), and steel bars (7) are arranged inside the refractory castable (8). The inner wall of the steel formwork (6) to the center of the furnace shell (1) is filled with lightweight spray paint (9). Fiber felt (11) and large wall bricks (10) are arranged sequentially from the outside to the inside on the inner wall of the furnace shell (1). Clay cement mortar (12) is arranged above the refractory castable (8) and lightweight spray paint (9) along the inner side of the large wall bricks (10) to the center of the furnace shell (1). Low creep clay bricks (13) are laid on top of the clay cement mortar (12).

2. The optimized blast furnace hot blast stove hearth structure according to claim 1, characterized in that: The height of the steel formwork (6) is the same as the height of the refractory castable (8).

3. The optimized blast furnace hot blast stove hearth structure according to claim 2, characterized in that: The height of the lightweight spray coating (9) is the same as the height of the refractory castable (8).

4. The optimized blast furnace hot blast stove hearth structure according to claim 1, characterized in that: The refractory castable is provided with reinforcing bars (7), and the two ends of the reinforcing bars (7) are respectively connected to the inner wall of the furnace shell (1) and the outer wall of the steel formwork (6).

5. The optimized blast furnace hot blast stove hearth structure according to claim 3, characterized in that: The furnace columns (3) are evenly arranged above the bottom plate of the furnace shell (1) and fixed with bolts.

6. The optimized blast furnace hot blast stove hearth structure according to claim 5, characterized in that: The height of the fiber felt (11) and the large wall bricks (10) is the same as the height of the furnace shell (1).

7. A construction method for an optimized blast furnace hot blast stove hearth structure according to any one of claims 1-6, characterized in that, Includes the following steps: S1. The furnace shell (1), skirt (2), furnace column (3), and steel section (4) steel structure are installed in place and firmly fixed by welding or mechanical connection; S2. The bottom plate of the furnace shell (1) is opened and a short pipe is installed at the opening position. The grouting material (5) of the furnace bottom is constructed through the short pipe. After the grouting is completed, the short pipe is cut off and the hole is sealed. S3. Install steel formwork (6) between the outermost furnace column (3) and the inner wall of the furnace shell (1) for refractory casting. The steel formwork (6) is perpendicular to the bottom plate of the furnace shell (1) and arranged around the circumference of the furnace shell (1). Weld the steel formwork (6) to the bottom plate of the furnace shell (1) and the side wall of the steel section (4). S4. Two-way reinforcing bars (7) are laid between the furnace shell (1) and the steel formwork (6). The two ends of the reinforcing bars (7) are welded to the inner wall of the furnace shell (1) and the outer wall of the steel formwork (6) respectively, and the reinforcing bars (7) are tied together. S5. Refractory castable is poured at the position where the steel reinforcement (7) is laid between the furnace shell (1) and the steel formwork (6); S6. Lightweight spray paint (9) is used to fill the space between the furnace center and the steel formwork (6), and the filling height is consistent with the height of the refractory castable. S7. After the construction of the refractory castable and lightweight spray coating (9) at the bottom of the furnace shell (1) is completed, the bottom of the furnace shell (1) is leveled after the structure is stable, and the construction of the large wall bricks (10) and fiber felt (11) is carried out. Fiber felt (11) is laid on the inner wall of the furnace shell (1), and large wall bricks (10) are built on the inner side of the fiber felt (11). The height of the fiber felt (11) and the large wall bricks (10) is consistent with that of the furnace shell (1). S8. In S7, when the height of the large wall bricks (10) is greater than the height of the low creep clay bricks (13) at the bottom of the furnace, clay cement mortar (12) is laid on top of the refractory castable (8) and the lightweight spray coating (9), and then two layers of low creep clay bricks (13) are laid.

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