An scr shaft furnace and a method of lining

Abstract

This invention discloses an SCR vertical shaft furnace and its construction method, comprising, from the inside out, a working layer of bricks, an insulating layer of bricks, insulating castable, a high-alumina ceramic fiber blanket, and a steel outer shell; three layers of burners with decreasing inner diameter arranged at intervals from top to bottom; and anti-collision blocks installed on the top of the furnace body. This effectively avoids production interruptions caused by refractory clogging of the copper outlet in the SCR vertical shaft furnace, and significantly reduces the risk of refractory detachment from the furnace diameter section affecting the purity of the molten copper and introducing inclusions. During production, no abnormalities occurred, such as clogging of the copper outlet, molten copper backflow into the burners, insufficient copper flow to meet casting speed, or abnormal oxygen content in the product. It also greatly improves the insulation performance of the vertical shaft furnace and effectively reduces the natural gas consumption per unit area in the furnace production process.

Description

Technical Field

[0001] This invention relates to the field of smelting furnace technology, specifically to an SCR vertical furnace and its construction method. Background Technology

[0002] SCR vertical shaft furnaces are the starting point of continuous casting and rolling production lines. They primarily melt solid copper materials into liquid copper before copper processing, providing raw material for the subsequent continuous casting of fixed copper ingots. Simultaneously, they control the furnace atmosphere and stabilize the oxygen content in the molten copper. Currently used vertical shaft furnaces offer advantages such as instant start-up and shutdown, high melting efficiency, energy saving and environmental protection, no copper molten metal accumulation, and relative safety. However, they also have several shortcomings in use: Firstly, refractory materials have a short service life and are prone to burn-off. The detached refractory material can enter the molten copper, forming inclusions and affecting product quality. Due to the overall short lifespan of domestically produced refractory materials, severe burn-off of the refractory material in the vertical shaft furnace body, either entirely or partially, occurs. The burnt-off refractory material directly mixes into the molten copper, forming inclusions that ultimately affect product quality, impacting indicators such as electrical conductivity, breaking strength, torsional strength, and drawing performance.

[0003] Secondly, it is prone to blockage accidents at the copper outlet of the SCR vertical furnace. During the production of SCR vertical furnaces, refractory materials may fall off or peel off. Under the influence of gravity, the detached refractory materials fall to the bottom of the furnace and reach the copper outlet along the sloping bottom. Tiny pieces of refractory material mix with the molten copper to form inclusions, while large pieces of refractory material, due to space constraints, cannot roll out smoothly from the copper outlet and become blocked at the outlet. This prevents the molten copper from flowing out smoothly from the copper outlet, ultimately leading to production accidents such as blockage at the copper outlet, backflow of molten copper into the burner, insufficient copper flow rate to meet the casting speed, and abnormal oxygen content in the product.

[0004] Thirdly, due to the continuous heating effect of the flame from the connected upper flow channel on the B-layer burner directly above the copper outlet, the copper material temperature in the flame outlet area of ​​the B-layer burner is higher than that in other areas. Furthermore, when an anomaly occurs in the B-layer burner, it cannot be quickly addressed due to the high-temperature upper flow channel below it. After the copper material above the B-layer burner melts into liquid copper, it cannot fall normally under its own weight due to the obstruction of other solid copper particles, and instead flows into the B-layer burner directly above the copper outlet, ultimately leading to frequent backflow of liquid copper into the B-layer burner. This blockage in the B-layer burner above the copper outlet results in uneven temperature distribution within the B-layer burner layer, significantly reducing the melting efficiency of the vertical furnace.

[0005] Fourth, the difference in construction methods leads to a shorter furnace lifespan. In the original construction method, bricks below the 10th layer were laid progressively from the 4th ring into the 1st ring inside the furnace, while refractory materials above the 11th layer were laid from the insulating castable towards the working layer bricks. This method, due to furnace shell deformation causing deviations in inner diameter, brick shape, insulating castable size control, and brick joint control, ultimately made it impossible to ensure the required furnace dimensions by the time the furnace was reached. Changes in furnace diameter and the difference in refractory material quality further impacted the overall service life of the vertical shaft furnace refractory materials. Frequent production accidents such as refractory material cracking, furnace collapse, and production interruptions occurred, and the handling of these accidents further damaged the refractory materials, leading to a gradual shortening of the furnace's service life. Ultimately, it became necessary to replace and rebuild the refractory materials to maintain production operations. The vertical furnace construction method in this invention adopts a method of building from the inner ring (first ring) of the furnace to the outer diameter, which effectively ensures the inner diameter of the furnace and avoids the influence caused by furnace shell error and brick size deviation, thus providing a strong guarantee for the efficient operation of the vertical furnace.

[0006] This invention addresses the need for high purity, thermal shock stability, and resistance to molten copper erosion in copper continuous casting and rolling production lines. It develops a refractory material perfectly suited for vertical shaft furnaces in these lines. Furthermore, by incorporating the characteristics of the refractory material, an innovative construction method is employed to maximize the synergistic effect between the construction method and the selection of different refractory materials. This avoids production failures caused by furnace defects, ensures continuous and stable production, extends the service life of the vertical shaft furnace, improves its insulation performance, reduces natural gas consumption, and saves on production costs. Summary of the Invention

[0007] The main objective of this invention is to provide an SCR vertical shaft furnace and a method for its construction, in order to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides an SCR vertical shaft furnace and its construction method, comprising a furnace body constructed of four layers of refractory material from the inside out; the refractory material, from the inside out, includes working layer bricks, insulating layer bricks, insulating castable, and high-alumina ceramic fiber blanket; the high-alumina ceramic fiber blanket is externally fitted with a steel structure shell; the furnace body is divided into a furnace bottom section, a furnace intersection, and a furnace top section from bottom to top, with a copper outlet channel and a copper outlet communicating with the copper outlet channel at the bottom end of the furnace bottom section; the furnace intersection, from top to bottom, includes a first transition zone, a first narrowing zone, a second transition zone, and a second narrowing zone; the first transition zone is connected to the furnace top section; the... The second narrowing zone is connected to the furnace bottom section; the inner diameter of the first narrowing zone is smaller than the inner diameter of the furnace top section; the inner diameter of the second narrowing zone is smaller than the inner diameter of the first narrowing zone; the inner diameter of the first transition zone decreases to connect the furnace top section with the first narrowing zone; the inner diameter of the second transition zone decreases to connect the first narrowing zone with the second narrowing zone; multiple sets of first burners are spaced circumferentially along the outer wall of the furnace top section adjacent to the first transition zone; multiple sets of second burners are spaced circumferentially along the upper edge of the first narrowing zone; multiple sets of third burners are spaced circumferentially along the upper edge of the second narrowing zone; multiple sets of anti-collision blocks are spaced circumferentially along the top inner wall of the furnace top section.

[0009] As a further improvement of the present invention, the bottom end of the furnace bottom section is provided with a supporting base; the supporting base is provided with an inclined surface facing the top end of the furnace bottom section.

[0010] As a further improvement of the present invention, the supporting base is constructed with furnace bottom bricks laid vertically; the height of the plane where the furnace bottom bricks are located near the copper outlet is less than the height of the plane where the furnace bottom bricks are located near the third burner, so as to form a straight slope.

[0011] As a further improvement of the present invention, the furnace bottom brick and the copper outlet channel are on the same straight line; the distance between the side of the furnace bottom brick adjacent to the third burner and the third burner is 38mm-48mm.

[0012] As a further improvement of the present invention, the furnace body gradually narrows from the inner diameter of 1900mm at the top section to the inner diameter of 1225mm in the second narrowing section.

[0013] As a further improvement of the present invention, the thickness of the fire-resistant layer on the furnace sidewall below the first burner is greater than the thickness of the fire-resistant layer on the furnace sidewall above the first burner.

[0014] As a further improvement of the present invention, the furnace body has a total height of 119 layers. The bottom of the furnace body has 4 rings of refractory layers from the inside to the outside from the 1st to the 10th layers. The 1st to the 4th layers have the 3rd and 4th rings of refractory layers. The 5th to the 10th layers have 4 rings of refractory layers.

[0015] As a further improvement of the present invention, the first burner, the second burner, and the third burner are inclined from the outside to the inside toward the furnace bottom section.

[0016] This invention provides a method for constructing an SCR vertical shaft furnace, comprising the following steps: Refractory material selection for S1, SCR vertical shaft furnace: The refractory materials used in SCR vertical shaft furnaces are divided into silicon nitride-bonded silicon carbide bricks, high alumina bricks, corundum insulating castables, corundum high-strength castables, ceramic fiber blankets, as well as silicon carbide high-temperature mortar, silicon carbide low-temperature mortar, high alumina mortar, silicon carbide ramming mix, etc. Main components and main performance indicators of silicon nitride-bonded silicon carbide bricks for S2 and SCR vertical shaft furnaces: Main components: SiC≥74%, Si3N4≥22%, Fe2O3%≤0.5%; Main performance indicators: Apparent porosity ≤15%, bulk density ≥2.65g / cm³ 3 Compressive strength at room temperature ≥160MPa, flexural strength at room temperature ≥45MPa, flexural strength at high temperature ≥45MPa (1400℃×0.5h), thermal conductivity ≥16W / m·K (1000℃), thermal expansion ≤0.6% (1200℃), thermal shock stability >50 cycles (1100℃×water cooling), softening start temperature under 0.2MPa load >1700℃; Main composition and main performance indicators of high-alumina bricks for S3 and SCR vertical shaft furnaces: Main components: Al2O3 ≥ 60%; Main performance indicators: Apparent porosity ≤24%, bulk density ≥2.4g / cm³ 3 The compressive strength at room temperature is ≥50 MPa, the softening start temperature under 0.2 MPa load is ≥1500℃, and the linear change rate is -0.4%~0.1% (1450℃×2h). Main components and performance indicators of S4 corundum insulating castable for SCR vertical shaft furnace Main components: Fe2O3 ≤ 1%, Al2O3 ≥ 70%, SiO2 ≥ 20% Main performance indicators: Bulk density 1.5~1.6g / cm³ 3 Flexural strength ≥ 5 MPa (110℃×24h), flexural strength ≥ 8 MPa (1250℃×5h), compressive strength ≥ 20 MPa (110℃×24h), compressive strength ≥ 25 MPa (1250℃×5h). Thermal conductivity ≤0.6W / m·K (1000℃), linear change rate ≤0.8% (1250℃×5h), water addition 12±1 (%).

[0017] Main Components and Performance Indicators of S5 High-Strength Corundum Castable for SCR Vertical Shaft Furnaces Main components: Fe2O3 ≤ 0.5%, Al2O3 ≥ 96%, SiO2 ≥ 0.5% Main performance indicators: Bulk density ≥ 3.0 g / cm³ 3 Flexural strength ≥11Mpa (110℃×24h), flexural strength ≥15Mpa (1250℃×5h), compressive strength ≥100Mpa (110℃×24h), compressive strength ≥120Mpa (1250℃×5h). Flow value ≥200mm, linear change rate ≤0.8% (1250℃×5h), water addition 5±0.4 (%).

[0018] Main Components and Performance Indicators of Ceramic Fiber Blanket for S6 and SCR Vertical Furnaces Main components: Al2O3 + SiO2 ≥ 80% Main performance indicators: thermal conductivity ≤0.2W / mK (1100℃), maximum operating temperature 1260℃ Main Components and Performance Indicators of S7, SCR Vertical Furnace Silicon Carbide High-Temperature Lining Mu Main composition: SiC ≥ 78%, Fe2O3 ≤ 0.5%, Al2O3 ≤ 7%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤1.0% (1450℃×5h) Main Components and Performance Indicators of Low-Temperature Silicon Carbide Lining for S8 and SCR Vertical Furnaces Main components: SiC ≥ 75%, Fe2O3 ≤ 0.5%, Al2O3 ≤ 7%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤1.0% (1450℃×5h) Main components and performance indicators of high-alumina lining mud for S9 and SCR vertical shaft furnaces Main components: Fe2O3 ≤ 1.0%, Al2O ≥ 60%, SiO2 ≥ 20% Key performance indicators: linear change rate ≤ 1.0% (1200℃ × 5h) Main components and performance indicators of S10 silicon carbide ramming mix for SCR vertical shaft furnace Main components: SiC ≥ 78%, Fe2O3 ≤ 0.5%, Al2O ≤ 6%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤ 0.5% (1450℃×5h), bulk density ≥ 2.6g / cm³ 3 Flexural strength ≥10 MPa (1250℃×5h), compressive strength ≥60 MPa (1250℃×5h) S11, the SCR vertical furnace has a shock-proof block below the charging port. The shock-proof block is composed of 309 stainless steel at the bottom and a copper surface layer. S12, Method for laying bricks in layers 1-4: The third and fourth rings of bricks in layers 1-4 are all made of high-alumina bricks; the third ring of layer 1 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 1 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the third ring of layer 2 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 2 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the third ring of layer 3 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 3 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the third ring of layer 4 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 4 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the brick joints between each layer are staggered to avoid straight joints; S13, Method for laying the 5th layer of bricks: The fifth layer is constructed entirely of high-alumina bricks, starting from the side directly opposite the copper outlet. The first ring uses D-1 type bricks; the second ring uses D-3 and D-4 type bricks in a 1:2 ratio; the third ring uses D-3 type bricks; and the fourth ring uses D-3 and D-4 type bricks in a 1:3 ratio. Standard wide bricks and standard straight bricks are used at the copper outlet. In the center of the first ring of bricks from the 5th to the 8th layer, there is a cylindrical sloping refractory material. This refractory material is cast using corundum high-strength castable for SCR vertical furnaces. After casting and drying for 24 hours, the furnace bottom bricks are used for vertical construction. The copper outlet end above the furnace bottom bricks is on the same straight line as the copper liquid flow channel of the copper outlet bricks. At the opposite end of the copper outlet, the furnace bottom bricks are 38mm below the A4 burner bricks, ultimately forming a straight slope. S14, Method for laying the 6th layer of bricks: The copper outlet is constructed vertically on both sides using standard straight high-alumina bricks, with a distance of 355mm between the bricks. In the first ring, the semicircle on the side of the copper outlet uses D-1 silicon carbide bricks, and the other semicircle uses D-1 high-alumina bricks. The second ring uses D-3 and D-4 bricks in a 1:2 ratio. The third ring uses D-3 high-alumina bricks. The fourth ring uses D-3 and D-4 bricks in a 1:3 ratio. S15, Method for laying the 7th layer of bricks: The outermost edges on both sides of the copper outlet are vertically constructed using standard straight bricks made of high alumina material; in the first ring, D-1 silicon carbide bricks are used; in the second ring, D-3 and D-2 bricks are used in a 1:2 ratio; in the third ring, D-3 high alumina bricks are used; and in the fourth ring, D-3 and D-4 bricks are used in a 1:3 ratio. S16, Method for laying the 8th layer of bricks: The outermost edges on both sides of the copper outlet are vertically constructed using standard straight bricks made of high-alumina material; in the first ring, D-1 silicon carbide bricks and standard straight bricks on the copper outlet side are used, with the silicon carbide standard straight bricks used on both sides of the copper outlet; the second ring uses D-3 and D-2 type bricks, laid in a 1:2 ratio; the third ring uses D-3 type high-alumina bricks; the fourth ring uses D-3 and D-4 type bricks, laid in a 1:3 ratio. S17, Method for laying the 9th layer of bricks; The outermost edges on both sides of the copper outlet are vertically constructed using standard straight bricks made of high-alumina material, with a distance of 355mm between the bricks; the first ring uses D-1 silicon carbide bricks; the second ring uses D-3 and D-2 bricks in a 1:2 ratio; the third ring uses D-3 high-alumina bricks; and the fourth ring uses D-3 and D-4 bricks in a 1:3 ratio. S18, Method for laying the 10th layer of bricks; The outermost edges on both sides of the copper outlet are vertically constructed using standard straight bricks made of high-alumina material, with a distance of 355mm between the bricks; in the first ring, ultra-thin silicon carbide bricks and D-1 type silicon carbide bricks are used; in the second ring, standard thin bricks made of high-alumina material, D-3 type high-alumina bricks, and D-2 type high-alumina bricks are used; in the third ring, standard thin bricks made of high-alumina material and D-3 type silicon carbide bricks are used; in the fourth ring, standard thin bricks made of high-alumina material, D-3 type high-alumina bricks, and D-4 type high-alumina bricks are used. S19, Method for laying the 11th layer of bricks: The outermost edges on both sides of the copper outlet are vertically constructed using standard straight bricks of high alumina material, with a distance of 355mm between the bricks; in the first ring, standard straight bricks of silicon carbide, ultra-thin silicon carbide bricks, and D-1 type silicon carbide bricks are used; in the second ring, standard thin bricks of high alumina material, D-3 type high alumina bricks, and D-2 type high alumina bricks are used; in the third ring, standard thin bricks of high alumina material and D-3 type silicon carbide bricks are used; in the fourth ring, standard thin bricks of high alumina material and D-4 type high alumina bricks are used. S20, Method for laying the 12th layer of bricks: The first ring uses silicon carbide shaped bricks, with cover bricks, straight bricks, and lintel bricks above the copper outlet, all of type D-1 bricks; the second ring uses D-2 type high-alumina bricks; the third ring uses D-3 type high-alumina bricks; and the fourth ring uses D-4 type high-alumina bricks. S21, Method for laying the 13th layer of bricks: The first lap used D-1 type silicon carbide bricks; the second lap used D-2 type high-alumina bricks; the third lap used D-3 type high-alumina bricks; and the fourth lap used D-4 type high-alumina bricks. S22, Method for laying the 14th layer of bricks: The copper outlet uses standard straight bricks made of silicon carbide; the first ring uses D-1 type silicon carbide bricks; the second ring uses D-2 type high-alumina bricks; the third ring uses D-3 type high-alumina bricks; and the fourth ring uses D-4 type high-alumina bricks. S23, Method for laying the 15th layer of bricks: The first round uses D-1 type silicon carbide bricks and standard thin silicon carbide bricks; the second round uses D-2 type high-alumina bricks, D-3 type high-alumina bricks, and thin high-alumina bricks; the third round uses D-3 type high-alumina bricks and thin high-alumina bricks; the fourth round uses D-3 type high-alumina bricks, D-4 type high-alumina bricks, and thin high-alumina bricks. S24, Method for laying the 16th layer of bricks: The first lap uses D-2S type silicon carbide bricks and D-1S type silicon carbide bricks; the second lap uses D-3 type high-alumina bricks and D-2 type high-alumina bricks. S25, Method for laying the 17th layer of bricks: The first lap uses D-2S type silicon carbide bricks and D-1S type silicon carbide bricks; the second lap uses D-3 type high-alumina bricks and D-2 type high-alumina bricks. S26, Method for laying the 18th layer of bricks: The first lap uses D-2S and D-1S silicon carbide bricks; the second lap uses D-3 and D-2 high-alumina bricks. S27, Method for laying the 19th layer of bricks: The first lap uses D-2S and D-1S silicon carbide bricks; the second lap uses D-3 and D-2 high-alumina bricks. S28, Method for laying the 20th layer of bricks: The first lap uses D-2S type silicon carbide bricks, and the second lap uses D-3 type high-alumina bricks and D-2 type high-alumina bricks. S29, Method for laying the 21st layer of bricks: The first lap uses D-2S and D-3S silicon carbide bricks; the second lap uses D-3 and D-2 high-alumina bricks. S30, Method for laying the 22nd layer of bricks: The first lap used D-2S and D-3S silicon carbide bricks; the second lap used D-3 high-alumina bricks. S31, Method for laying the 23rd layer of bricks: The first lap uses D-2 and D-3 silicon carbide bricks; the second lap uses D-3 and D-4 high-alumina bricks. S32, Method for laying the 24th layer of bricks: The first lap uses D-3 type silicon carbide bricks, and the second lap uses D-3 type high alumina bricks. S33, Method for laying the 25th layer of bricks: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks. S34, Method for laying the 26th layer of bricks: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks. S35, Method for laying the 27th layer of bricks: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks. S36, Method for laying the 28th layer of bricks: The first round used D-3 type silicon carbide bricks and standard thin silicon carbide bricks; the second round used D-3 type high-alumina bricks and standard thin high-alumina bricks. S37, Method for laying the 29th layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S38, Method for laying the 30th layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S39, Method for laying the 31st layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S40, Method for laying the 32nd layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S41, Method for laying bricks in layers 33 to 36: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks and D-4 type high-alumina bricks. S42, Method for laying bricks in layers 37 to 40: The first lap used D-3 type silicon carbide bricks; the second lap used D-4 type high-alumina bricks. S43, Method for laying the 41st layer of bricks: The first round used D-3 type silicon carbide bricks and standard silicon carbide thin bricks; the second round used D-4 type high-alumina bricks and standard high-alumina thin bricks. S44, Method for laying bricks from layer 42 to layer 106: The first ring of each layer uses D-3 type silicon carbide bricks; the second ring uses D-3 type high-alumina bricks and D-4 type high-alumina bricks. S45, Method for laying bricks in layers 107 to 109: There are three layers of bricks in total, each layer of which uses PN-2 and PN-3 type bricks made of silicon carbide material, laid in a 1:1 ratio; S46, Installation of anti-collision devices on layers 110 to 111: The anti-collision device uses stainless steel and copper ingots cast from copper. The stainless steel is on the back of the copper ingot, which is mounted on a steel plate with a certain shape for easy removal and hoisting.

[0019] The beneficial effects of this invention are reflected in: 1. The service life of refractory materials is significantly extended, and the loss and shedding of refractory materials are significantly reduced, greatly improving the quality of electrical copper wire rod products. The service life of refractory materials is extended, and the annual loss of furnace diameter and the single-sided loss of refractory bricks are reduced. With the reduction of refractory material loss, the inclusion of copper liquid is also reduced, and the quality of electrical copper wire rod products is also improved.

[0020] 2. The SCR vertical furnace operates stably and efficiently. During production, there were no instances of large-area or overall detachment or peeling of refractory materials. When the top bricks at the charging port are impacted by copper plates during charging, the size of the missing corners will be reduced, preventing blockage of the copper outlet. Furthermore, the missing corners will not continue to break and fall off. The detached refractory materials can be smoothly rolled out of the copper outlet of the vertical furnace under the pressure of the combustion mixture inside the furnace and can be removed in the slag skimming process.

[0021] This effectively avoids production interruptions caused by refractory clogging of the copper outlet in SCR vertical furnaces. It also greatly reduces the risk of refractory detachment from the furnace diameter affecting the purity of the molten copper and causing inclusions. During production, no abnormal situations occurred, such as clogging of the copper outlet in the vertical furnace, backflow of molten copper into the burner, insufficient copper flow rate to meet the casting speed, or abnormal oxygen content in the product.

[0022] 3. This method avoids production accidents such as refractory material cracking, furnace collapse, and production interruption caused by poor masonry methods and procedures. While possessing stable and reliable refractory materials suitable for copper melting, the implementation of this masonry method improves the overall structure of the vertical furnace refractory materials, enhances the stability of the vertical furnace operation, and avoids vertical furnace production accidents that could affect the operation of the SCR continuous casting and rolling production line. During operation, the refractory bricks are stable, the furnace shell temperature is below 150℃, the furnace shell steel structure is stable, no deformation has occurred, and no furnace shell maintenance has been carried out.

[0023] 4. Significantly improves the overall service life of the furnace, including the furnace steel shell and refractory materials, greatly reducing the maintenance cost of the vertical furnace. Attached Figure Description

[0024] Figure 1 This is an overall schematic diagram of an SCR vertical furnace according to the present invention; Explanation of reference numerals in the attached figures: 1. Furnace body; 2. Working layer bricks; 3. Insulation layer bricks; 4. Insulation castable; 5. High-alumina ceramic fiber blanket; 6. Steel structure shell; 7. Furnace bottom section; 8. Furnace intersection; 9. Furnace top section; 10. Copper tapping channel; 11. Copper tapping port; 12. First transition zone; 13. First narrowing zone; 14. Second transition zone; 15. Second narrowing zone; 16. First burner; 17. Second burner; 18. Third burner; 19. Support base; 20. Sloping surface; 21. Furnace bottom bricks. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the described embodiments are merely some, not all, of the embodiments of this invention. Unless otherwise specified, the embodiments and features described in this application can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] In one embodiment, see Figure 1The present invention discloses an SCR vertical furnace, comprising a furnace body 1 constructed of four layers of refractory material from the inside out. The refractory material, from the inside out, includes working layer bricks 2, insulating layer bricks 3, insulating castable 4, and high-alumina ceramic fiber blanket 5. A steel structure shell 6 is provided outside the high-alumina ceramic fiber blanket 5. The furnace body 1 is divided into a furnace bottom section 7, a furnace intersection 8, and a furnace top section 9 from bottom to top. The bottom end of the furnace bottom section 7 is inclinedly provided with a copper outlet channel 10 and a copper outlet 11 communicating with the copper outlet channel 10. The furnace intersection 8, from top to bottom, includes a first transition zone 12, a first narrowing zone 13, a second transition zone 14, and a second narrowing zone 15. The first transition zone 12 is connected to the furnace top section 9, and the second narrowing zone 15 is connected to... The furnace bottom section 7 is connected. The inner diameter of the first narrowing zone 13 is smaller than the inner diameter of the furnace top section 9. The inner diameter of the second narrowing zone 15 is smaller than the inner diameter of the first narrowing zone 13. The inner diameter of the first transition zone 12 decreases to connect the furnace top section 9 with the first narrowing zone 13. The inner diameter of the second transition zone 14 decreases to connect the first narrowing zone 13 with the second narrowing zone 15. Multiple sets of first burners 16 are spaced circumferentially along the outer wall of the furnace top section 9 adjacent to the first transition zone 12. Multiple sets of second burners 17 are spaced circumferentially along the upper edge of the first narrowing zone 13. Multiple sets of third burners 18 are spaced circumferentially along the upper edge of the second narrowing zone 15. Multiple sets of anti-collision blocks are spaced circumferentially along the top inner wall of the furnace top section 9.

[0027] Furthermore, a support base 19 is provided at the bottom end of the furnace bottom section 7, and an inclined surface 20 is provided on the support base 19 facing the top end of the furnace bottom section 7.

[0028] Preferably, the support base 19 is cylindrical and is cast using high-strength corundum castable for SCR vertical furnaces. Alternatively, the support base 19 can be replaced by an integral precast brick made of silicon nitride combined with silicon carbide. This can save the 24 hours of molding and drying time required for casting with high-strength corundum castable for SCR vertical furnaces, and the overall strength of the refractory will be increased. This avoids the risk of copper seepage due to the refractory penetrating into the voids of the castable during production and increases the difficulty of removing the refractory during the second furnace repair.

[0029] Furthermore, the bottom bricks 21 are vertically laid on the supporting base 19, and the height of the plane where the bottom bricks 21 are adjacent to the copper outlet 11 is less than the height of the plane where the bottom bricks 21 are adjacent to the third burner 18 to form a straight slope.

[0030] Preferably, the furnace bottom brick 21 is made of high-alumina brick.

[0031] Furthermore, the furnace bottom brick 21 and the copper outlet channel 10 are on the same straight line, and the distance between the side of the furnace bottom brick 21 adjacent to the third burner 18 and the third burner 18 is 38mm-48mm.

[0032] Preferably, the bottom end of the furnace bottom brick 21 on the higher side is flush with the top end of the seventh layer of bricks in the furnace body 1, and the bottom end of the furnace bottom brick 21 on the lower side adjacent to the copper outlet 11 is flush with the top end of the fifth layer of bricks in the furnace body 1.

[0033] Furthermore, the furnace body 1 gradually narrows from the inner diameter of the top section 9 (1900mm) to the inner diameter of the second narrowing zone 15 (1225mm).

[0034] Preferably, the internal furnace chamber of the overall furnace body 1 is shaped like a "pen tip".

[0035] Furthermore, the thickness of the refractory layer on the side wall of the furnace body 1 below the first burner 16 is greater than the thickness of the refractory layer on the side wall of the furnace body 1 above the first burner 16.

[0036] Preferably, the working layer brick 2, the insulation layer brick 3, the insulation castable 4, and the high-alumina ceramic fiber blanket 5 are all refractory materials.

[0037] Furthermore, the furnace body 1 has a total of 119 layers. From the 1st to the 10th layer at the bottom of the furnace body 1, four rings of refractory layers are built from the inside out. From the 1st to the 4th layer, three and four rings of refractory layers are built. From the 5th to the 10th layer, four rings of refractory layers are built.

[0038] Preferably, the first ring of layers 5 to 10 is the working layer brick 2.

[0039] Furthermore, the first burner 16, the second burner 17, and the third burner 18 are inclined from the outside to the inside toward the furnace bottom section 7.

[0040] Preferably, there are 8 first burners 16, and 7 second burners 17 and 7 third burners 18.

[0041] This invention provides a method for constructing an SCR vertical shaft furnace, comprising the following steps: The refractory materials used in S1 and SCR shaft furnaces mainly consist of... Based on the application of the refractory materials used in SCR vertical furnaces, the refractory materials of SCR vertical furnaces can be divided into five parts: working layer bricks 2, insulation layer bricks 3, insulation castable 4, high-alumina ceramic fiber blanket for furnace shell protection 5, and high-strength castable 5.

[0042] Based on material composition, the refractory materials used in SCR vertical shaft furnaces can be divided into silicon nitride-bonded silicon carbide bricks, high-alumina bricks, corundum insulating castable 4, corundum high-strength castable, ceramic fiber blankets, as well as silicon carbide high-temperature mortar, silicon carbide low-temperature mortar, high-alumina mortar, silicon carbide ramming mix, etc.

[0043] Main Components and Performance Indicators of S2 Silicon Nitride Bonded Silicon Carbide Bricks for SCR Vertical Shaft Furnaces Main components: SiC ≥ 74%, Si3N4 ≥ 22%, Fe2O 3% ≤ 0.5% Main performance indicators: Apparent porosity ≤15%, bulk density ≥2.65g / cm³ 3Compressive strength at room temperature ≥160MPa, flexural strength at room temperature ≥45MPa, flexural strength at high temperature ≥45MPa (1400℃×0.5h), thermal conductivity ≥16W / m·K (1000℃), thermal expansion ≤0.6% (1200℃), thermal shock stability >50 cycles (1100℃×water cooling), softening start temperature under 0.2MPa load >1700℃.

[0044] Specifications and models: The specifications and models of silicon nitride-bonded silicon carbide bricks for SCR vertical shaft furnaces are shown in the table below. Table 1 Specifications of Silicon Nitride-Bound Silicon Carbide Bricks for SCR Shaft Furnaces Main Components and Performance Indicators of High-Alumina Bricks for S3 and SCR Shaft Furnaces Main components: Al2O3 ≥ 60% Main performance indicators: Apparent porosity ≤24%, bulk density ≥2.4g / cm³ 3 Compressive strength at room temperature ≥50 MPa, softening start temperature under 0.2 MPa load ≥1500℃, linear change rate: -0.4%~0.1% (1450℃×2h) Specifications and models: The specifications and models of high-alumina bricks for SCR vertical shaft furnaces are shown in the table below. Table 2 Specifications of High Alumina Bricks for SCR Shaft Furnaces Main components and performance indicators of S4 corundum insulating castable for SCR vertical shaft furnace Main components: Fe2O3 ≤ 1%, Al2O3 ≥ 70%, SiO2 ≥ 20% Main performance indicators: Bulk density 1.5~1.6g / cm³ 3 Flexural strength ≥ 5 MPa (110℃×24h), flexural strength ≥ 8 MPa (1250℃×5h), compressive strength ≥ 20 MPa (110℃×24h), compressive strength ≥ 25 MPa (1250℃×5h). Thermal conductivity ≤0.6W / m·K (1000℃), linear change rate ≤0.8% (1250℃×5h), water addition 12±1 (%).

[0045] Main Components and Performance Indicators of S5 High-Strength Corundum Castable for SCR Vertical Shaft Furnaces Main components: Fe2O3 ≤ 0.5%, Al2O3 ≥ 96%, SiO2 ≥ 0.5% Main performance indicators: Bulk density ≥ 3.0 g / cm³ 3Flexural strength ≥11Mpa (110℃×24h), flexural strength ≥15Mpa (1250℃×5h), compressive strength ≥100Mpa (110℃×24h), compressive strength ≥120Mpa (1250℃×5h). Flow value ≥200mm, linear change rate ≤0.8% (1250℃×5h), water addition 5±0.4 (%).

[0046] Main Components and Performance Indicators of Ceramic Fiber Blanket for S6 and SCR Vertical Furnaces Main components: Al2O3 + SiO2 ≥ 80% Main performance indicators: thermal conductivity ≤0.2W / mK (1100℃), maximum operating temperature 1260℃ Main Components and Performance Indicators of S7, SCR Vertical Furnace Silicon Carbide High-Temperature Lining Mu Main composition: SiC ≥ 78%, Fe2O3 ≤ 0.5%, Al2O3 ≤ 7%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤1.0% (1450℃×5h) Main Components and Performance Indicators of Low-Temperature Silicon Carbide Lining for S8 and SCR Vertical Furnaces Main components: SiC ≥ 75%, Fe2O3 ≤ 0.5%, Al2O3 ≤ 7%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤1.0% (1450℃×5h) Main components and performance indicators of high-alumina lining mud for S9 and SCR vertical shaft furnaces Main components: Fe2O3 ≤ 1.0%, Al2O ≥ 60%, SiO2 ≥ 20% Key performance indicators: linear change rate ≤ 1.0% (1200℃ × 5h) Main components and performance indicators of S10 silicon carbide ramming mix for SCR vertical shaft furnace Main components: SiC ≥ 78%, Fe2O3 ≤ 0.5%, Al2O ≤ 6%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤ 0.5% (1450℃×5h), bulk density ≥ 2.6g / cm³ 3 Flexural strength ≥10 MPa (1250℃×5h), compressive strength ≥60 MPa (1250℃×5h) S11, Anti-collision block below the charging port of SCR vertical furnace. The anti-collision block is composed of a base of 309 stainless steel and a surface layer of copper.

[0047] II. Implementation of Masonry Methods A vertical furnace is a vertical furnace with a circular cross-section. From the inside out, the vertical furnace consists of the following components: 2. Working layer bricks; 3. Insulation layer bricks; 4. Insulation castable; 5. High-alumina ceramic fiber blanket; and 6. Steel structure shell.

[0048] The vertical shaft furnace uses natural gas or liquefied petroleum gas as fuel. After being mixed with air, the fuel is delivered to 23 burners. Spark plugs ignite the burners, and the copper material is preheated in the top layer (the first burner, layer 16), continuously heated in the middle layer (the second burner, layer 17), and finally reaches the bottom layer (the third burner, layer 18). As the temperature gradually increases, the copper material begins to slowly melt, forming a 3-4 mm liquid layer at the bottom of the furnace. Under its own weight, the molten copper flows out through the copper outlet 11 via the inclined furnace bottom. As the copper material melts, it moves downwards within the vertical shaft furnace, thus continuously supplying molten copper (there is no molten pool in this furnace) to subsequent processes.

[0049] Because molten copper flows at the bottom of the vertical shaft furnace, the structure and thickness of the refractory material below the 16th layer of the first burner are greater than those above the 16th layer of the first burner. From a vertical cross-section, the furnace structure formed by the refractory lining of the vertical shaft furnace resembles the outer edge of a sharpened pencil, like an upside-down pencil. The third burner has the most layers of refractory lining (18 layers), and the overall refractory material thickness is the thickest.

[0050] S12, the method of laying bricks for layers 1 to 4.

[0051] Table 3. Quantity and type of bricks for layers 1-4 from Figure 1 The longitudinal section of the vertical furnace determines the bricklaying positions. The third and fourth rings of bricks in layers 1-4 are all made of high-alumina bricks. The third ring of layer 1 uses only D-3 type high-alumina bricks, requiring a total of 29 bricks. The fourth ring of layer 1 uses D-3 and D-4 type high-alumina bricks, laid in a 1:3 ratio, with 7 D-3 bricks and 22 D-4 bricks used. The third ring of layer 2 uses only D-3 type high-alumina bricks, requiring a total of 29 bricks. The fourth ring of layer 2 uses D-3 and D-4 type high-alumina bricks, laid in a 1:3 ratio, with 7 D-3 bricks and 22 D-4 bricks used. The third ring of layer 3 uses only D-3 type high-alumina bricks, requiring a total of 29 bricks. The fourth ring of layer 3 uses D-3 and D-4 type high-alumina bricks, laid in a 1:3 ratio, with 7 D-3 bricks and 22 D-4 bricks used. The third ring of the fourth layer uses only D-3 type high-alumina bricks, requiring a total of 29 bricks. The fourth ring of the fourth layer uses D-3 and D-4 type high-alumina bricks, mixed in a 1:3 ratio, with 7 D-3 bricks and 22 D-4 bricks used. The brick joints between each layer are staggered to avoid straight joints.

[0052] S13, Method for laying the fifth layer of bricks.

[0053] The fifth layer is constructed entirely of high-alumina bricks, starting from the side directly opposite the copper outlet 11. The first ring uses 19 D-1 type bricks. The second ring uses D-3 and D-4 type bricks in a 1:2 ratio. The third ring uses 26 D-3 type bricks, and the fourth ring uses D-3 and D-4 type bricks in a 1:3 ratio. At the copper outlet 11, 8 standard wide bricks and 3 standard straight bricks are used.

[0054] The first ring of bricks from the 5th to the 8th layer has a cylindrical sloping refractory material 20 in the center, which is cast using high-strength corundum castable for SCR vertical furnaces. After casting and drying for 24 hours, the furnace bottom bricks 21 are vertically laid. The copper outlet 11 end above the furnace bottom brick 21 is aligned with the copper flow channel of the copper outlet 11 brick. At the opposite end of the copper outlet 11, the furnace bottom brick 21 is positioned 38mm below the A4 burner brick, ultimately forming a straight slope.

[0055] S14, Method for laying the 6th layer of bricks.

[0056] Two standard straight high-alumina bricks are used on each side of the copper outlet 11, for a total of four bricks, laid vertically with a spacing of 355mm between them. In the first ring, ten D-1 silicon carbide bricks are used in the semicircle on one side of the copper outlet 11, and ten D-1 high-alumina bricks are used in the other semicircle. The second ring uses D-3 and D-4 bricks in a 1:2 ratio. The third ring uses 26 D-3 high-alumina bricks. The fourth ring uses D-3 and D-4 bricks in a 1:3 ratio.

[0057] S15, Method for laying the 7th layer of bricks.

[0058] Two standard straight high-alumina bricks are used on each side of the outermost edge of the copper outlet 11, for a total of four bricks, laid vertically. The first ring uses 21 D-1 silicon carbide bricks. The second ring uses D-3 and D-2 bricks in a 1:2 ratio. The third ring uses 26 D-3 high-alumina bricks. The fourth ring uses D-3 and D-4 bricks in a 1:3 ratio.

[0059] S16, Method for laying the 8th layer of bricks.

[0060] The outermost edges of both sides of the copper outlet 11 are constructed using 1.5 standard straight bricks of high-alumina material on each side, totaling 3 bricks, laid vertically. In the first ring, 20 D-1 silicon carbide bricks and 2 standard straight bricks are used on each side of the copper outlet 11, with one silicon carbide standard straight brick on each side. The second ring uses D-3 and D-2 type bricks, laid in a 1:2 ratio. The third ring uses 26 D-3 type high-alumina bricks. The fourth ring uses D-3 and D-4 type bricks, laid in a 1:3 ratio.

[0061] S17, Method for laying the 9th layer of bricks.

[0062] Two standard straight high-alumina bricks are used on each side of the outermost edge of the copper outlet 11, for a total of four bricks, laid vertically with a spacing of 355mm between them. The first ring uses 21 D-1 silicon carbide bricks. The second ring uses D-3 and D-2 bricks in a 1:2 ratio. The third ring uses 26 D-3 high-alumina bricks. The fourth ring uses D-3 and D-4 bricks in a 1:3 ratio.

[0063] S18, Method for laying the 10th layer of bricks.

[0064] Two standard straight bricks of high-alumina material are used on each of the outermost edges of the copper outlet 11, for a total of four bricks, laid vertically with a distance of 355mm between them. In the first ring, four ultra-thin silicon carbide bricks and 17 D-1 type silicon carbide bricks are used. In the second ring, four standard thin high-alumina bricks, six D-3 type high-alumina bricks, and 14 D-2 type high-alumina bricks are used. In the third ring, four standard thin high-alumina bricks and 25 D-3 type silicon carbide bricks are used. In the fourth ring, four standard thin high-alumina bricks, four D-3 type high-alumina bricks, and 22 D-4 type high-alumina bricks are used.

[0065] S19, Method for laying the 11th layer of bricks.

[0066] The outermost edges of both sides of the copper outlet 11 are constructed using 1.5 standard straight bricks of high-alumina material on each side, totaling 3 bricks, laid vertically with a spacing of 355mm between bricks. In the first ring, 4 standard straight silicon carbide bricks, 6 ultra-thin silicon carbide bricks, and 10 D-1 type silicon carbide bricks are used. In the second ring, 6 standard thin high-alumina bricks, 6 D-3 type high-alumina bricks, and 14 D-2 type high-alumina bricks are used. In the third ring, 6 standard thin high-alumina bricks and 20 D-3 type silicon carbide bricks are used. In the fourth ring, 6 standard thin high-alumina bricks and 22 D-4 type high-alumina bricks are used.

[0067] S20, the method for laying the 12th layer of bricks.

[0068] The first ring uses silicon carbide shaped bricks throughout, with one cover brick, three straight large bricks, one lintel brick for the copper outlet 11, and 12 D-1 type bricks above it. The second ring uses 14 D-2 type high-alumina bricks throughout. The third ring uses 20 D-3 type high-alumina bricks throughout. The fourth ring uses 22 D-4 type high-alumina bricks throughout.

[0069] S21, Method for laying the 13th layer of bricks.

[0070] The first lap uses 12 D-1 type silicon carbide bricks. The second lap uses 14 D-2 type high-alumina bricks. The third lap uses 20 D-3 type high-alumina bricks. The fourth lap uses 22 D-4 type high-alumina bricks.

[0071] S22, Method for laying the 14th layer of bricks.

[0072] At copper outlet position 11, four standard straight silicon carbide bricks are used. The first ring uses 14 D-1 type silicon carbide bricks. The second ring uses 14 D-2 type high-alumina bricks. The third ring uses 20 D-3 type high-alumina bricks. The fourth ring uses 22 D-4 type high-alumina bricks.

[0073] S23, Method for laying the 15th layer of bricks.

[0074] Round 1 uses 17 D-1 type silicon carbide bricks and 4 standard thin silicon carbide bricks. Round 2 uses 13 D-2 type high-alumina bricks, 8 D-3 type high-alumina bricks, and 4 thin high-alumina bricks. Round 3 uses 24 D-3 type high-alumina bricks and 4 thin high-alumina bricks. Round 4 uses 7 D-3 type high-alumina bricks, 16 D-4 type high-alumina bricks, and 4 thin high-alumina bricks.

[0075] S24, Method for laying the 16th layer of bricks.

[0076] The first lap used 12 D-2S type silicon carbide bricks and 10 D-1S type silicon carbide bricks. The second lap used 9 D-3 type high-alumina bricks and 17 D-2 type high-alumina bricks.

[0077] S25, Method for laying the 17th layer of bricks.

[0078] The first lap used 15 D-2S type silicon carbide bricks and 8 D-1S type silicon carbide bricks. The second lap used 11 D-3 type high-alumina bricks and 15 D-2 type high-alumina bricks.

[0079] S26, Method for laying the 18th layer of bricks.

[0080] The first lap used 18 D-2S type silicon carbide bricks and 5 D-1S type silicon carbide bricks. The second lap used 15 D-3 type high-alumina bricks and 2 D-2 type high-alumina bricks.

[0081] S27, Method for laying the 19th layer of bricks.

[0082] The first lap used 21 D-2S type silicon carbide bricks and 3 D-1S type silicon carbide bricks. The second lap used 18 D-3 type high-alumina bricks and 9 D-2 type high-alumina bricks.

[0083] S28, Method for laying the 20th layer of bricks.

[0084] The first lap used 24 D-2S type silicon carbide bricks. The second lap used 22 D-3 type high-alumina bricks and 6 D-2 type high-alumina bricks.

[0085] S29, Method for laying the 21st layer of bricks.

[0086] The first lap used 21 D-2S type silicon carbide bricks and 4 D-3S type silicon carbide bricks. The second lap used 24 D-3 type high-alumina bricks and 4 D-2 type high-alumina bricks.

[0087] S30, the method for laying the 22nd layer of bricks.

[0088] The first lap used 18 D-2S type silicon carbide bricks and 8 D-3S type silicon carbide bricks. The second lap used 29 D-3 type high-alumina bricks.

[0089] S31, Method for laying the 23rd layer of bricks.

[0090] The first lap used 22 D-2 type silicon carbide bricks and 4 D-3 type silicon carbide bricks. The second lap used 25 D-3 type high-alumina bricks and 4 D-4 type high-alumina bricks.

[0091] S32, Method for laying the 24th layer of bricks.

[0092] The first lap used 16 D-3 type silicon carbide bricks. The second lap used 22 D-3 type high-alumina bricks.

[0093] S33, Method for laying the 25th layer of bricks.

[0094] The first lap used 16 D-3 type silicon carbide bricks. The second lap used 22 D-3 type high-alumina bricks.

[0095] S34, Method for laying the 26th layer of bricks.

[0096] The first lap used 16 D-3 type silicon carbide bricks. The second lap used 22 D-3 type high-alumina bricks.

[0097] S35, Method for laying the 27th layer of bricks.

[0098] The first lap used 16 D-3 type silicon carbide bricks. The second lap used 22 D-3 type high-alumina bricks.

[0099] S36, Method for laying the 28th layer of bricks.

[0100] The first lap used 16 D-3 type silicon carbide bricks and 16 standard thin silicon carbide bricks. The second lap used 18 D-3 type high-alumina bricks and 16 standard thin high-alumina bricks.

[0101] S37, Method for laying bricks in the 29th layer.

[0102] The first lap used 15 D-3S type silicon carbide bricks and 12 D-2S type silicon carbide bricks. The second lap used 21 D-3 type high-alumina bricks and 9 D-4 type high-alumina bricks.

[0103] S38, Method for laying the 30th layer of bricks.

[0104] The first lap used 17 D-3S type silicon carbide bricks and 10 D-2S type silicon carbide bricks. The second lap used 19 D-3 type high-alumina bricks and 11 D-4 type high-alumina bricks.

[0105] S39, Method for laying the 31st layer of bricks.

[0106] The first lap used 22 D-3S type silicon carbide bricks and 6 D-2S type silicon carbide bricks. The second lap used 14 D-3 type high-alumina bricks and 17 D-4 type high-alumina bricks.

[0107] S40, the method for laying the 32nd layer of bricks.

[0108] The first lap used 24 D-3S type silicon carbide bricks and 4 D-2S type silicon carbide bricks. The second lap used 11 D-3 type high-alumina bricks and 20 D-4 type high-alumina bricks.

[0109] S41, Method for laying bricks in layers 33 to 36.

[0110] The first lap used 29 D-3 type silicon carbide bricks. The second lap used 7 D-3 type high-alumina bricks and 25 D-4 type high-alumina bricks.

[0111] S42, Method for laying bricks in layers 37 to 40.

[0112] The first lap used 22 D-3 type silicon carbide bricks. The second lap used 25 D-4 type high-alumina bricks.

[0113] S43, Method for laying the 41st layer of bricks.

[0114] The first lap used 22 D-3 type silicon carbide bricks and 16 standard silicon carbide thin bricks. The second lap used 25 D-4 type high-alumina bricks and 16 standard high-alumina thin bricks.

[0115] S44, Method for laying bricks from the 42nd to the 106th layer.

[0116] The first ring of each layer uses 29 D-3 type silicon carbide bricks. The second ring uses 7 D-3 type high-alumina bricks and 25 D-4 type high-alumina bricks.

[0117] S45, Method for laying bricks in layers 107 to 109.

[0118] There are three layers of bricks, each layer using PN-2 and PN-3 type bricks made of silicon carbide, laid in a 1:1 ratio, with 35 of each type of brick used.

[0119] S46, Anti-collision devices installed on layers 110 to 111 The anti-collision device uses stainless steel and copper ingots cast from copper. The stainless steel is on the back of the copper ingot, which is mounted on a steel plate with a certain shape for easy removal and hoisting.

[0120] In one embodiment, when producing the outer steel shell (boiler steel) of the vertical shaft furnace, the length between layer C and the furnace charging port can be increased by 0.6 meters. The laying of bricks in layers 42 to 106 of S44 can be optimized to lay bricks in layers 42 to 114, while the laying method remains unchanged. That is, the first ring of each layer uses 29 D-3 type silicon carbide bricks, and the second ring uses 7 D-3 type high-alumina bricks and 25 D-4 type high-alumina bricks.

[0121] This optimization increases the height of the vertical furnace, which allows for more time for the copper material to fall and preheat inside the furnace, thus making full use of the heat inside the furnace and reducing heat loss.

[0122] In S46, the copper ingots used in the installation of the anti-collision devices on layers 110 and 111 are designed in the shape of an "axe," with one end larger than the other. The larger end is 150mm thick, and the smaller end is 130mm thick. During installation, the copper ingot is mounted on a stainless steel casing with the smaller end facing upwards and the larger end downwards. This way, when copper plates are added during production, the inclined anti-collision device causes the copper plates to collide with it and slide down the inclined ingot, landing on the opposite side, in the middle, and at the point of impact. This facilitates the even distribution of the copper plates, enhances heat preservation, increases the melting rate, and saves on fuel consumption.

[0123] Working Principle: The SCR vertical shaft furnace has a height of 11.7 meters from the copper outlet (level 11) to the charging port. Its cross-section is circular. The overall structure, from the inside out, consists of: working layer bricks (2), insulation layer bricks (3), insulation castable (4), high-alumina ceramic fiber blanket (5), and welded steel outer shell (6). The working layer bricks (2), insulation layer bricks (3), insulation castable (4), and high-alumina ceramic fiber blanket (5) are all refractory materials. There is a charging port at the top of the furnace, below which are two rows of copper bricks. The vertical shaft furnace used in the SCR4500 continuous casting and rolling production line has 22 burners arranged in three layers, labeled A, B, and C from bottom to top. Layer A has 7 burners, layer B has 7, and layer C has 8. The C row of burners mainly preheats the copper material, while the A and B rows of burners mainly perform melting. The diameter of the vertical furnace chamber gradually decreases from 1900mm for the C-layer burners to 1225mm for the A-layer burners. The overall interior of the furnace chamber is shaped like a "pen tip". Finally, a copper outlet 11 is set below the A-layer burners. The molten copper flows out from the copper outlet 11 through the sloping furnace bottom.

[0124] After repeated trials and practices, the SCR refractory materials produced using this method and the vertical furnaces constructed using this method achieved the following technical results: First, the service life of refractory materials has been significantly extended, and the loss and shedding of refractory materials due to burn-off has been significantly reduced, greatly improving the quality of electrical copper wire blanks. The service life of the refractory materials used has increased from a minimum of 1 year and an average of 2 years to a maximum of 5 years and an average of 4 years. The annual burn-off loss of the furnace diameter has been reduced from 25 mm and more than 13 mm on one side of the refractory bricks to a maximum of 9 mm per year and less than 5 mm on one side of the refractory bricks.

[0125] Due to reduced refractory material burn-off, copper inclusions in the molten copper are also reduced, thus improving the quality of electrical copper wire blanks. Excluding the influence of the copper material itself, if high-purity cathode copper is used exclusively, the product resistivity can be as low as below 0.01695 Ω•mm² / m, while the national standard requires ≤0.01707 Ω•mm² / m. The breaking value exceeds 34 turns (for a 250mm sample length, 25 forward turns followed by reverse to the breaking point), and there are no defects in 15×15 twisting. Drawing performance is consistently improved; the produced products can be used to draw copper wires smaller than 0.08mm, and can be used in multi-head wire drawing machines to draw wire blanks, with an average drawing rate exceeding 0.4 times / ton (approximately 1 breakage every 2.5 tons).

[0126] Secondly, the SCR vertical shaft furnace operates stably and efficiently. No large-area or overall detachment or peeling of refractory material occurred during production. Before this method, refractory material measuring 140mm × 120mm × 95mm blocked the copper outlet 11 of the vertical shaft furnace. After using this method, only chipped corners of the furnace top bricks caused by impact from copper plates during charging occurred, with the largest size not exceeding 32mm × 18mm × 10mm. Furthermore, the chipped corners did not continue to break and detach. Refractory material of this size can smoothly roll out of the copper outlet 11 under the pressure of the combustion mixture inside the furnace and can be removed in the skimming process.

[0127] This effectively prevented production interruptions in the SCR vertical furnace due to refractory blockage at the copper outlet 11, and significantly reduced the risk of refractory detachment from the furnace diameter affecting the purity of the molten copper and introducing inclusions. During production, no abnormalities occurred, including blockage at the copper outlet 11, molten copper backflow into the burners, insufficient copper flow to meet casting speed, or abnormal oxygen content in the product. The number of blocked burners decreased from 5 to 0, ensuring sufficient molten copper supply for production lines with a capacity exceeding 32 t / h. This significantly reduced potential safety risks, such as burns, that might occur during the handling of blockages at the copper outlet 11 or during burn-off blockage.

[0128] Thirdly, it avoids the problem of molten copper backflow in the B-layer burners directly above the copper outlet 11 of the vertical furnace. The burners in the vertical furnace have been rearranged to avoid being placed directly above the copper outlet 11 (directly above the chute), thus bypassing the area with temperatures reaching 200℃. This facilitates the inspection of burner combustion, timely adjustment and handling of the vertical furnace firepower, and prevention of burner blockage. It also significantly improves the temperature uniformity of the B-layer burners in the vertical furnace, increasing the furnace melting efficiency and achieving an energy-saving effect of reducing natural gas consumption by 390 m³ per day.

[0129] Fourth, it avoids production accidents such as refractory material cracking, furnace collapse, and production interruption caused by poor masonry methods and procedures. While possessing stable and reliable refractory materials suitable for copper melting, the implementation of this masonry method improves the overall structure of the vertical furnace refractory materials and enhances the stability of the vertical furnace operation. There have been no vertical furnace production accidents that have affected the operation of the SCR continuous casting and rolling production line. There have been 0 instances of refractory bricks falling during operation. The furnace shell temperature is below 150℃, the furnace shell steel structure is stable, there has been no deformation, and no furnace shell maintenance has been carried out.

[0130] Fifth, it significantly extends the overall service life of the furnace, including the furnace shell and refractory materials, from requiring repair and maintenance every year to a stable operation period of four years. This greatly reduces the maintenance costs of the vertical shaft furnace.

[0131] Sixth, it greatly improves the heat preservation performance of the vertical furnace, makes full use of the heat generated by the burner of the vertical furnace, reduces the heat loss rate by 12%, and reduces the gas consumption by 1m³ / t.

[0132] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An SCR vertical shaft furnace, characterized in that, The furnace body (1) consists of four layers of refractory material from the inside out; the refractory material from the inside out includes working layer bricks (2), insulation layer bricks (3), insulation castable (4), and high-alumina ceramic fiber blanket (5); the high-alumina ceramic fiber blanket (5) is surrounded by a steel structure shell (6); the furnace body (1) is divided into a furnace bottom section (7), a furnace intersection (8), and a furnace top section (9) from bottom to top; the bottom end of the furnace bottom section (7) is inclined with a copper outlet channel (10) and a copper outlet (11) connected to the copper outlet channel (10); the furnace intersection (8) from top to bottom includes a first transition zone (12), a first narrowing zone (13), a second transition zone (14), and a second narrowing zone (15); the first transition zone (12) is connected to the furnace top section (9); the second narrowing zone (15) is connected to the furnace bottom section (9). 7) Connection; The inner diameter of the first narrowing zone (13) is smaller than the inner diameter of the furnace top section (9); The inner diameter of the second narrowing zone (15) is smaller than the inner diameter of the first narrowing zone (13); The inner diameter of the first transition zone (12) decreases to connect the furnace top section (9) with the first narrowing zone (13); The inner diameter of the second transition zone (14) decreases to connect the first narrowing zone (13) with the second narrowing zone (15); Multiple sets of first burners (16) are spaced circumferentially on the outer wall of the furnace top section (9) adjacent to the first transition zone (12); Multiple sets of second burners (17) are spaced circumferentially on the first narrowing zone (13); Multiple sets of third burners (18) are spaced circumferentially on the second narrowing zone (15); Multiple sets of anti-collision blocks are spaced circumferentially on the top inner wall of the furnace top section (9).

2. The SCR vertical furnace according to claim 1, characterized in that: The bottom end of the furnace bottom section (7) is provided with a supporting base (19); the supporting base (19) is provided with an inclined surface (20) facing the top end of the furnace bottom section (7).

3. An SCR vertical shaft furnace according to claim 2, characterized in that: The supporting base (19) is vertically constructed with furnace bottom bricks (21); the height of the plane where the furnace bottom bricks (21) are adjacent to the copper outlet (11) is less than the height of the plane where the furnace bottom bricks (21) are adjacent to the third burner (18) to form a straight slope.

4. An SCR vertical shaft furnace according to claim 3, characterized in that: The furnace bottom brick (21) and the copper outlet channel (10) are on the same straight line; the distance between the side of the furnace bottom brick (21) adjacent to the third burner (18) and the third burner (18) is 38mm-48mm.

5. An SCR vertical shaft furnace according to claim 4, characterized in that: The furnace body (1) gradually shrinks from the inner diameter of the top section (9) of 1900mm to the inner diameter of the second narrowing section (15) of 1225mm.

6. An SCR vertical shaft furnace according to claim 5, characterized in that: The thickness of the heat-resistant layer on the side wall of the furnace body (1) below the first burner (16) is greater than the thickness of the heat-resistant layer on the side wall of the furnace body (1) above the first burner (16).

7. An SCR vertical shaft furnace according to claim 6, characterized in that: The furnace body (1) has a total height of 119 layers. The bottom of the furnace body (1) has 4 rings of refractory layers from the inside to the outside from the 1st to the 10th layers. The 1st to the 4th layers have the 3rd and 4th rings of refractory layers. The 5th to the 10th layers have 4 rings of refractory layers.

8. An SCR vertical furnace according to claim 7, characterized in that: The first burner (16), the second burner (17), and the third burner (18) are inclined from the outside to the inside toward the bottom section (7) of the furnace.

9. A method for constructing an SCR vertical shaft furnace according to any one of claims 1-7, comprising the following steps: Refractory material selection for S1, SCR vertical shaft furnace: The refractory materials used in SCR vertical furnaces are divided into silicon nitride-bonded silicon carbide bricks, high alumina bricks, corundum insulating castable (4), corundum high-strength castable, ceramic fiber blankets, as well as silicon carbide high-temperature mortar, silicon carbide low-temperature mortar, high alumina mortar, silicon carbide ramming material, etc. Main components and main performance indicators of silicon nitride-bonded silicon carbide bricks for S2 and SCR vertical shaft furnaces: Main components: SiC≥74%, Si3N4≥22%, Fe2O3%≤0.5%; Main performance indicators: Apparent porosity ≤15%, bulk density ≥2.65g / cm³ 3 Compressive strength at room temperature ≥160MPa, flexural strength at room temperature ≥45MPa, flexural strength at high temperature ≥45MPa (1400℃×0.5h), thermal conductivity ≥16W / m·K (1000℃), thermal expansion ≤0.6% (1200℃), thermal shock stability >50 cycles (1100℃×water cooling), softening start temperature under 0.2MPa load >1700℃; Main composition and main performance indicators of high-alumina bricks for S3 and SCR vertical shaft furnaces: Main components: Al2O3 ≥ 60%; Main performance indicators: Apparent porosity ≤24%, bulk density ≥2.4g / cm³ 3 The compressive strength at room temperature is ≥50 MPa, the softening start temperature under 0.2 MPa load is ≥1500℃, and the linear change rate is -0.4%~0.1% (1450℃×2h). Main components and performance indicators of S4 corundum insulating castable for SCR vertical shaft furnace Main components: Fe2O3 ≤ 1%, Al2O3 ≥ 70%, SiO2 ≥ 20% Main performance indicators: Bulk density 1.5~1.6g / cm³ 3 Flexural strength ≥ 5 MPa (110℃×24h), flexural strength ≥ 8 MPa (1250℃×5h), compressive strength ≥ 20 MPa (110℃×24h), compressive strength ≥ 25 MPa (1250℃×5h). Thermal conductivity ≤0.6W / m·K (1000℃), linear change rate ≤0.8% (1250℃×5h), water addition 12±1 (%). Main Components and Performance Indicators of S5 High-Strength Corundum Castable for SCR Vertical Shaft Furnaces Main components: Fe2O3 ≤ 0.5%, Al2O3 ≥ 96%, SiO2 ≥ 0.5% Main performance indicators: Bulk density ≥ 3.0 g / cm³ 3 Flexural strength ≥11Mpa (110℃×24h), flexural strength ≥15Mpa (1250℃×5h), compressive strength ≥100Mpa (110℃×24h), compressive strength ≥120Mpa (1250℃×5h). Flow value ≥200mm, linear change rate ≤0.8% (1250℃×5h), water addition 5±0.4 (%). Main Components and Performance Indicators of Ceramic Fiber Blanket for S6 and SCR Vertical Furnaces Main components: Al2O3 + SiO2 ≥ 80% Main performance indicators: thermal conductivity ≤0.2W / mK (1100℃), maximum operating temperature 1260℃ Main Components and Performance Indicators of S7, SCR Vertical Furnace Silicon Carbide High-Temperature Lining Mu Main composition: SiC ≥ 78%, Fe2O3 ≤ 0.5%, Al2O3 ≤ 7%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤1.0% (1450℃×5h) Main Components and Performance Indicators of Low-Temperature Silicon Carbide Lining for S8 and SCR Vertical Furnaces Main components: SiC ≥ 75%, Fe2O3 ≤ 0.5%, Al2O3 ≤ 7%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤1.0% (1450℃×5h) Main components and performance indicators of high-alumina lining mud for S9 and SCR vertical shaft furnaces Main components: Fe2O3 ≤ 1.0%, Al2O ≥ 60%, SiO2 ≥ 20% Key performance indicators: linear change rate ≤ 1.0% (1200℃ × 5h) Main components and performance indicators of S10 silicon carbide ramming mix for SCR vertical shaft furnace Main components: SiC ≥ 78%, Fe2O3 ≤ 0.5%, Al2O ≤ 6%, SiO2 ≤ 5% Main performance indicators: linear change rate ≤ 0.5% (1450℃×5h), bulk density ≥ 2.6g / cm³ 3 Flexural strength ≥10 MPa (1250℃×5h), compressive strength ≥60 MPa (1250℃×5h) S11, the SCR vertical furnace has a shock-proof block below the charging port. The shock-proof block is composed of 309 stainless steel at the bottom and a copper surface layer. S12, Method for laying bricks in layers 1-4: The third and fourth rings of bricks in layers 1-4 are all made of high-alumina bricks; the third ring of layer 1 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 1 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the third ring of layer 2 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 2 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the third ring of layer 3 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 3 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the third ring of layer 4 is entirely made of D-3 type high-alumina bricks; the fourth ring of layer 4 uses D-3 and D-4 type high-alumina bricks in a 1:3 ratio; the brick joints between each layer are staggered to avoid straight joints; S13, Method for laying the 5th layer of bricks: The fifth layer is made entirely of high-alumina bricks, starting from the side directly opposite the copper outlet (11). The first ring uses D-1 type bricks; the second ring uses D-3 and D-4 type bricks, laid in a 1:2 ratio; the third ring uses D-3 type bricks; the fourth ring uses D-3 and D-4 type bricks, laid in a 1:3 ratio; standard wide bricks and standard straight bricks are used at the copper outlet (11). In the center of the first ring of bricks from the 5th to the 8th layer, there is a cylindrical inclined surface (20) of refractory material. This refractory material is cast using high-strength corundum castable for SCR vertical furnace. After casting and drying for 24 hours, the furnace bottom bricks (21) are used for vertical construction. The copper outlet (11) end above the furnace bottom brick (21) is on the same straight line as the copper liquid flow channel of the copper outlet (11) brick. In the opposite end of the copper outlet (11), the furnace bottom brick (21) is 38mm below the A4 burner brick, which finally forms a straight slope. S14, Method for laying the 6th layer of bricks: The copper outlet (11) is vertically constructed on both sides using standard straight bricks of high alumina material, with a distance of 355mm between the bricks; in the first ring, the semicircle on the side of the copper outlet (11) uses D-1 silicon carbide material bricks, and the other semicircle uses D-1 high alumina material bricks; the second ring uses D-3 and D-4 type bricks, constructed in a ratio of 1:2; the third ring uses D-3 type high alumina material bricks; the fourth ring uses D-3 and D-4 type bricks, constructed in a ratio of 1:

3. S15, Method for laying the 7th layer of bricks: The outermost edges of the copper outlet (11) are vertically constructed using standard straight bricks of high alumina material; in the first ring, D-1 silicon carbide bricks are used; in the second ring, D-3 and D-2 type bricks are used, constructed in a ratio of 1:2; in the third ring, D-3 type high alumina material bricks are used; in the fourth ring, D-3 and D-4 type bricks are used, constructed in a ratio of 1:

3. S16, Method for laying the 8th layer of bricks: The outermost edges of both sides of the copper outlet (11) are vertically constructed using standard straight bricks of high alumina material; in the first ring, D-1 silicon carbide material bricks and standard straight bricks on the sides of the copper outlet (11) are used, with silicon carbide standard straight bricks used on both sides of the copper outlet (11); in the second ring, D-3 and D-2 type bricks are used, constructed in a 1:2 ratio; in the third ring, D-3 type high alumina material bricks are used; in the fourth ring, D-3 and D-4 type bricks are used, constructed in a 1:3 ratio. S17, Method for laying the 9th layer of bricks; The outermost edges of the copper outlet (11) are vertically constructed using standard straight bricks of high alumina material, with a distance of 355mm between the bricks; in the first ring, D-1 silicon carbide bricks are used; in the second ring, D-3 and D-2 bricks are used in a 1:2 ratio; in the third ring, D-3 high alumina bricks are used; and in the fourth ring, D-3 and D-4 bricks are used in a 1:3 ratio. S18, Method for laying the 10th layer of bricks; The outermost edges of the copper outlet (11) are vertically constructed using standard straight bricks of high alumina material, with a distance of 355mm between the bricks; in the first ring, silicon carbide ultra-thin bricks and D-1 type silicon carbide bricks are used; in the second ring, standard thin bricks of high alumina material, D-3 type high alumina material bricks, and D-2 type high alumina material bricks are used; in the third ring, standard thin bricks of high alumina material and D-3 type silicon carbide bricks are used; in the fourth ring, standard thin bricks of high alumina material, D-3 type high alumina material bricks, and D-4 type high alumina material bricks are used. S19, Method for laying the 11th layer of bricks: The outermost edges of the copper outlet (11) are vertically constructed using standard straight bricks of high alumina material, with a distance of 355mm between the bricks; in the first ring, standard straight bricks of silicon carbide, ultra-thin silicon carbide bricks, and D-1 type silicon carbide bricks are used; in the second ring, standard thin bricks of high alumina material, D-3 type high alumina bricks, and D-2 type high alumina bricks are used; in the third ring, standard thin bricks of high alumina material and D-3 type silicon carbide bricks are used; in the fourth ring, standard thin bricks of high alumina material and D-4 type high alumina bricks are used. S20, Method for laying the 12th layer of bricks: The first ring uses silicon carbide shaped bricks, and the upper part of the copper outlet (11) uses cover bricks, straight bricks, large bricks, and lintel bricks for the copper outlet (11), D-1 type bricks; the second ring uses D-2 type high alumina bricks; the third ring uses D-3 type high alumina bricks; the fourth ring uses D-4 type high alumina bricks. S21, Method for laying the 13th layer of bricks: The first lap used D-1 type silicon carbide bricks; the second lap used D-2 type high-alumina bricks; the third lap used D-3 type high-alumina bricks; and the fourth lap used D-4 type high-alumina bricks. S22, Method for laying the 14th layer of bricks: The copper outlet (11) uses standard straight bricks made of silicon carbide; the first ring uses D-1 type silicon carbide bricks; the second ring uses D-2 type high alumina bricks; the third ring uses D-3 type high alumina bricks; the fourth ring uses D-4 type high alumina bricks. S23, Method for laying the 15th layer of bricks: The first round uses D-1 type silicon carbide bricks and standard thin silicon carbide bricks; the second round uses D-2 type high-alumina bricks, D-3 type high-alumina bricks, and thin high-alumina bricks; the third round uses D-3 type high-alumina bricks and thin high-alumina bricks; the fourth round uses D-3 type high-alumina bricks, D-4 type high-alumina bricks, and thin high-alumina bricks. S24, Method for laying the 16th layer of bricks: The first lap uses D-2S type silicon carbide bricks and D-1S type silicon carbide bricks; the second lap uses D-3 type high-alumina bricks and D-2 type high-alumina bricks. S25, Method for laying the 17th layer of bricks: The first lap uses D-2S type silicon carbide bricks and D-1S type silicon carbide bricks; the second lap uses D-3 type high-alumina bricks and D-2 type high-alumina bricks. S26, Method for laying the 18th layer of bricks: The first lap uses D-2S and D-1S silicon carbide bricks; the second lap uses D-3 and D-2 high-alumina bricks. S27, Method for laying the 19th layer of bricks: The first lap uses D-2S and D-1S silicon carbide bricks; the second lap uses D-3 and D-2 high-alumina bricks. S28, Method for laying the 20th layer of bricks: The first lap uses D-2S type silicon carbide bricks, and the second lap uses D-3 type high-alumina bricks and D-2 type high-alumina bricks. S29, Method for laying the 21st layer of bricks: The first lap uses D-2S and D-3S silicon carbide bricks; the second lap uses D-3 and D-2 high-alumina bricks. S30, Method for laying the 22nd layer of bricks: The first lap used D-2S and D-3S silicon carbide bricks; the second lap used D-3 high-alumina bricks. S31, Method for laying the 23rd layer of bricks: The first lap uses D-2 and D-3 silicon carbide bricks; the second lap uses D-3 and D-4 high-alumina bricks. S32, Method for laying the 24th layer of bricks: The first lap uses D-3 type silicon carbide bricks, and the second lap uses D-3 type high alumina bricks. S33, Method for laying the 25th layer of bricks: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks. S34, Method for laying the 26th layer of bricks: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks. S35, Method for laying the 27th layer of bricks: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks. S36, Method for laying the 28th layer of bricks: The first round used D-3 type silicon carbide bricks and standard thin silicon carbide bricks; the second round used D-3 type high-alumina bricks and standard thin high-alumina bricks. S37, Method for laying the 29th layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S38, Method for laying the 30th layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S39, Method for laying the 31st layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S40, Method for laying the 32nd layer of bricks: The first lap used D-3S and D-2S silicon carbide bricks; the second lap used D-3 and D-4 high-alumina bricks. S41, Method for laying bricks in layers 33 to 36: The first lap used D-3 type silicon carbide bricks; the second lap used D-3 type high-alumina bricks and D-4 type high-alumina bricks. S42, Method for laying bricks in layers 37 to 40: The first lap used D-3 type silicon carbide bricks; the second lap used D-4 type high-alumina bricks. S43, Method for laying the 41st layer of bricks: The first round used D-3 type silicon carbide bricks and standard silicon carbide thin bricks; the second round used D-4 type high-alumina bricks and standard high-alumina thin bricks. S44, Method for laying bricks from layer 42 to layer 106: The first ring of each layer uses D-3 type silicon carbide bricks; the second ring uses D-3 type high-alumina bricks and D-4 type high-alumina bricks. S45, Method for laying bricks in layers 107 to 109: There are three layers of bricks in total, each layer of which uses PN-2 and PN-3 type bricks made of silicon carbide material, laid in a 1:1 ratio; S46, Installation of anti-collision devices on layers 110 to 111: The anti-collision device uses stainless steel and copper ingots cast from copper. The stainless steel is on the back of the copper ingot, which is mounted on a steel plate with a certain shape for easy removal and hoisting.

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