Unfired sliding plate brick and preparation method thereof

Abstract

The invention discloses an unfired sliding plate brick and a preparation method thereof, and belongs to the field of preparation of refractory materials. The unfired sliding plate brick comprises the following components in percentage by mass: 65-70% of granular aggregate and 30-35% of co-grinding powder, and the total percentage of the granular aggregate and the co-grinding powder is 100%. The granular aggregate comprises the following components in percentage by mass: 55%-60% of fused magnesia particles and 40%-45% of fused magnesium-zirconium sand particles. The co-grinding powder comprises the following components in percentage by mass in the unfired sliding plate brick: 10%-15% of fused magnesia powder, 8%-12% of fused magnesium zirconium sand powder, 5%-10% of alpha-Al2O3 micro powder, 5%-10% of aluminum-silicon alloy powder and 1%-3% of boron carbide powder. The preparation method adopts an unfired process. Under the condition that an inorganic binding agent is used, the unfired sliding plate brick with the characteristics of excellent slag corrosion resistance, thermal shock resistance, high strength, high hardness and the like can be prepared, so that the increasingly stringent use requirements of the sliding plate brick are met.

Description

Technical Field

[0001] This invention belongs to the field of refractory materials technology, and more specifically, relates to a non-fired sliding plate brick and its preparation method. Background Technology

[0002] With the rapid development of my country's equipment manufacturing industry and the continuous advancement of steelmaking processes, the requirements for slide block bricks are becoming increasingly stringent, especially the need for slide block bricks that are resistant to thermal shock, erosion from high-temperature molten steel and slag, and have a long service life. Currently, the magnesia-carbon and alumina-zirconium-carbon slide block bricks commonly used in continuous casting all suffer from varying degrees of cracking, roughening, and oxidation, affecting further improvements in service life and thus failing to better meet the requirements of new continuous casting technologies. Furthermore, magnesia-carbon and alumina-zirconium-carbon slide block bricks employ a sintering process, resulting in high energy consumption and severe environmental pollution.

[0003] In recent years, a series of new sliding plate bricks have been prepared using a non-fired process, which has certain energy-saving and environmental protection effects. However, the binder of non-fired sliding plate bricks is phenolic resin, which decomposes during application to produce volatile organic compounds (VOCs). These VOCs pollute the air and are harmful to human health. The carbon dioxide produced by the carbon oxidation of the resin contributes to global warming. In addition, the decomposition and oxidation of phenolic resin in the mid-temperature range (300-700℃) significantly reduces the mid-temperature strength of the sliding plate, reaching a strength trough around 600℃. This makes the sliding surface of the sliding plate prone to roughening, breakage, and poor erosion resistance of the casting holes during use. Furthermore, the anti-slip area of ​​the sliding plate (around 600℃) is prone to chipping, posing a potential safety hazard to steelmaking continuous casting, thus limiting the widespread application of non-fired sliding plate bricks.

[0004] Chinese patent application number CN202111205147.0, published on December 7, 2021, discloses an environmentally friendly low-carbon aluminum-carbon non-fired sliding plate brick and its preparation method, belonging to the technical field of refractory materials for steelmaking continuous casting. The environmentally friendly low-carbon aluminum-carbon non-fired sliding plate brick comprises the following raw materials by weight percentage: 65-70% corundum aggregate, 5-15% fine corundum powder, 10-15% aluminum-silicon alloy powder, 5-8% activated alumina micro powder, 2-4% carbon, 1-4% boron-containing additives, and 5-6% inorganic binder. The preparation process involves pressing the mixed raw materials under 150 MPa, drying at 110-200℃, drilling holes, drying again at 100-120℃ to remove moisture from the holes, and then grinding, binding, shelling, and coating processes to produce the environmentally friendly low-carbon aluminum-carbon non-fired sliding plate brick. Although this invention uses an environmentally friendly inorganic binder to replace phenolic resin and solves the problems caused by the use of phenolic resin in traditional processes, it mainly uses corundum as the raw material for the preparation of non-fired sliding plate bricks. When corundum and inorganic binder are used together to prepare non-fired sliding plate bricks, the performance of the prepared non-fired sliding plate bricks often fails to meet the requirements for use, and there are problems such as insufficient resistance to slag erosion and insufficient strength. Summary of the Invention

[0005] 1. The problem to be solved

[0006] To address the problem that the performance of unfired slide block bricks prepared using inorganic binders in existing technologies is difficult to meet the requirements for use, this invention provides an unfired slide block brick and its preparation method. This method can produce unfired slide block bricks with excellent slag erosion resistance, thermal shock resistance, high strength, and high hardness by using inorganic binders to reduce carbon content, thereby meeting the increasingly stringent requirements for slide block operation.

[0007] 2. Technical Solution

[0008] To solve the above problems, the present invention adopts the following technical solution.

[0009] A non-fired sliding plate brick includes granular aggregate and co-ground powder, wherein the mass percentage of granular aggregate is 65% to 70%, the mass percentage of co-ground powder is 30% to 35%, and the total percentage of the two is 100%.

[0010] The composition of the granular aggregate and its mass percentage in the granular aggregate are: 55% to 60% fused magnesia sand particles and 40% to 45% fused magnesia zircon sand particles.

[0011] The composition of the co-ground powder and its mass percentage in the unfired slide block brick are as follows: 10%–15% fused magnesia powder, 8%–12% fused magnesia-zirconium powder, 5%–10% α-Al2O3 micro powder, 5%–10% aluminum-silicon alloy powder and 1%–3% boron carbide powder.

[0012] In one optional embodiment, the binder is further comprising liquid aluminum dihydrogen phosphate, wherein the liquid aluminum dihydrogen phosphate contains: 9% ≥ Al2O3 content ≥ 7%, 34% ≥ P2O5 content ≥ 32%, and R2O content ≤ 0.12%, and the mass of the binder is 5% to 6% of the total mass of the granular aggregate and the co-ground powder.

[0013] In one optional embodiment, the fused magnesia particles have three particle sizes: 3-1 mm, 1-0.5 mm, and 0.5-0 mm. The mass fractions of the fused magnesia particles of each particle size are: 10-15 parts of fused magnesia particles with a particle size of 3-1 mm, 8-12 parts of fused magnesia particles with a particle size of 1-0.5 mm, and 5-10 parts of fused magnesia particles with a particle size of 0.5-0 mm.

[0014] In one optional embodiment, the fused silica sand particles contain MgO content ≥ 96.3%, CaO content ≤ 1.5%, SiO2 content ≤ 1.3%, and the content of CaO+SiO2+Al2O3+Fe2O3 ≤ 3.4%.

[0015] In one optional embodiment, the particle size of the fused magnesium zircon sand particles includes three types: 3-1 mm, 1-0.5 mm, and 0.5-0 mm. The mass fractions of the fused magnesium zircon sand particles of each particle size are: 8-12 parts of fused magnesium zircon sand particles with a particle size of 3-1 mm, 8-12 parts of fused magnesium zircon sand particles with a particle size of 1-0.5 mm, and 5-10 parts of fused magnesium zircon sand particles with a particle size of 0.5-0 mm.

[0016] In one optional embodiment, the fused magnesium zirconium sand particles contain: MgO content ≥90%, ZrO2 content ≥4%, SiO2 content ≤2.5%, Fe2O3 content ≤0.6%, and CaO content ≤1.2%.

[0017] In one optional embodiment, the aluminum-silicon alloy powder contains: Al content ≥79.2%, active Al content ≥75.5%, Fe content ≤0.2%, Al+Si content ≥99.2%, and Cu content ≤0.1%.

[0018] In one optional embodiment, the boron carbide contains: B4C content ≥ 95%, B... 总 The content of C is ≥75%. 总 The content of free carbon is ≥21%, the content of B2O3 is ≤0.15%, the content of free carbon is ≤3%, and the content of free carbon is ≤0.3%.

[0019] In one optional embodiment, the α-Al2O3 micro powder contains: Al2O3 content ≥ 99.5%, SiO2 content ≤ 0.1%, Fe2O3 content ≤ 0.8%, and R2O content ≤ 0.2%.

[0020] A method for preparing the above-mentioned non-fired sliding plate brick includes the following steps:

[0021] Step 1: Preparation of co-milled powder: The co-milled powder is prepared by uniformly mixing fused magnesia powder, fused magnesia-zirconium powder, aluminum-silicon alloy powder, boron carbide and α-Al2O3 micro powder according to the mass parts.

[0022] Step 2: Preparation of granular aggregate: The fused magnesia sand particles and fused magnesia zircon sand particles are uniformly mixed according to the mass fraction to obtain granular aggregate;

[0023] Step 3: Mixing: Dry mix the granular aggregate for 1-3 minutes, then add the binder and wet mix for 6-8 minutes, and finally add the co-ground powder and mix for 25-35 minutes to obtain the mixture;

[0024] Step 4: Molding: Press the mixture into shape to obtain brick blanks, and let them cool naturally for 8 hours;

[0025] Step 5: Drying: Place the brick blanks in a drying kiln. The initial temperature upon entering the kiln is 60℃, and drying at this temperature should last for at least 2 hours. Increase the temperature to 120℃ and dry for at least 2 hours. Increase the temperature to 150℃ and dry for at least 4 hours. Increase the temperature to 180℃ and dry for at least 4 hours. Increase the temperature to between 200 and 230℃ and dry for at least 15 hours. The total drying time should be at least 27 hours. After removing the bricks from the kiln, select qualified semi-finished products.

[0026] Step Six: Applying a hoop;

[0027] Step 7: Grinding;

[0028] Step 8: Apply a veneer, coat the surface, inspect and package the product to obtain the finished product.

[0029] 3. Beneficial effects

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] (1) The present invention provides a non-fired sliding plate brick, which introduces fused magnesium zircon sand and fused magnesium sand as raw materials. This allows the non-fired sliding plate brick to still have excellent slag erosion resistance, thermal shock resistance, high strength, and high hardness even when using inorganic binders. This increases the erosion resistance of the sliding plate, improves the strength of the sliding plate, and extends the service life of the sliding plate brick.

[0032] (2) The present invention provides a non-fired sliding plate brick, which uses an inorganic binder and does not introduce a large amount of carbon source, thus greatly reducing the carbon content and reducing the carbon content introduced into the molten steel during the steel casting process, so as to meet the needs of steel plants to produce low-carbon steel and ultra-clean steel.

[0033] (3) The present invention provides a method for preparing non-fired skateboard bricks, which eliminates the firing stage of skateboard bricks, shortens the production cycle of skateboard bricks, and reduces production costs. Detailed Implementation

[0034] Exemplary embodiments of the present invention are described in detail below. While these exemplary embodiments have been described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be implemented and various changes may be made to the invention without departing from its spirit and scope. The more detailed description of embodiments of the invention below is not intended to limit the scope of the claimed invention, but is merely illustrative and does not limit the description of the features and characteristics of the invention, in order to suggest the best mode for carrying out the invention and to enable those skilled in the art to practice it. Therefore, the scope of the invention is defined only by the appended claims.

[0035] A non-fired sliding plate brick comprises granular aggregate and co-ground powder, wherein the mass percentage of granular aggregate is 65% to 70%, the mass percentage of co-ground powder is 30% to 35%, and the total percentage of both is 100%.

[0036] The composition of the granular aggregate and its mass percentage in the granular aggregate are: 55% to 60% fused magnesia sand particles and 40% to 45% fused magnesia zircon sand particles.

[0037] The particle size of fused magnesia includes three types: 3-1 mm, 1-0.5 mm, and 0.5-0 mm. The mass fractions of fused magnesia particles of each particle size are: 10-15 parts for fused magnesia particles with a particle size of 3-1 mm, 8-12 parts for fused magnesia particles with a particle size of 1-0.5 mm, and 5-10 parts for fused magnesia particles with a particle size of 0.5-0 mm.

[0038] The particle size of fused magnesium zircon sand includes three types: 3-1 mm, 1-0.5 mm, and 0.5-0 mm. The mass fractions of fused magnesium zircon sand particles of each particle size are: 8-12 parts for 3-1 mm, 8-12 parts for 1-0.5 mm, and 5-10 parts for 0.5-0 mm.

[0039] By using the above-mentioned reasonable particle size distribution to make the particles pack in a density-packed manner, the density of the resulting material can be improved, thereby improving the performance of the final unfired sliding plate brick.

[0040] The composition of the co-ground powder and its mass percentage in the unfired slide block bricks are as follows: 10%–15% fused magnesia powder, 8%–12% fused magnesia-zirconium powder, 5%–10% α-Al₂O₃ micro powder, 5%–10% aluminum-silicon alloy powder, and 1%–3% boron carbide powder. The particle size of the fused magnesia powder, fused magnesia-zirconium powder, and aluminum-silicon alloy powder is 0–0.075 mm, the particle size of the boron carbide powder is 0–0.023 mm, and the particle size of the α-Al₂O₃ micro powder is 0.002 mm–0.003 mm.

[0041] The binder used in the non-fired sliding plate bricks is liquid aluminum dihydrogen phosphate. In the liquid aluminum dihydrogen phosphate: 9% ≥ Al2O3 content ≥ 7%, 34% ≥ P2O5 content ≥ 32%, and R2O content ≤ 0.12%. The mass of the binder is 5%–6% of the total mass of the granular aggregate and co-ground powder. This binder is inorganic, does not introduce a large amount of carbon source, greatly reduces the carbon content, and reduces the carbon content introduced into the molten steel during the casting process, thus meeting the requirements of steel mills for producing low-carbon steel and ultra-clean steel.

[0042] In fused magnesia granules and fused magnesia powder, the content of MgO is ≥96.3%, the content of CaO is ≤1.5%, the content of SiO2 is ≤1.3%, and the content of CaO+SiO2+Al2O3+Fe2O3 is ≤3.4%.

[0043] In fused magnesium zircon sand particles and powders: MgO content ≥90%, ZrO2 content ≥4%, SiO2 content ≤2.5%, Fe2O3 content ≤0.6%, and CaO content ≤1.2%.

[0044] In aluminum-silicon alloy powder: Al content ≥79.2%, active Al content ≥75.5%, Fe content ≤0.2%, Al+Si content ≥99.2%, and Cu content ≤0.1%.

[0045] In boron carbide: the content of B4C is ≥95%, B 总 The content of C is ≥75%. 总 The content of free carbon is ≥21%, the content of B2O3 is ≤0.15%, the content of free carbon is ≤3%, and the content of free carbon is ≤0.3%.

[0046] In α-Al2O3 micro powder: Al2O3 content ≥99.5%, SiO2 content ≤0.1%, Fe2O3 content ≤0.8%, and R2O content ≤0.2%.

[0047] The aforementioned unburned sliding plate bricks, by introducing fused magnesia-zirconium sand and fused magnesia sand as raw materials, enable the unburned sliding plate bricks to still have excellent slag erosion resistance, thermal shock resistance, high strength, and high hardness even when using inorganic binders. This increases the erosion resistance and strength of the sliding plate, thereby extending the service life of the sliding plate bricks.

[0048] The preparation method of non-fired sliding plate bricks includes the following steps:

[0049] Step 1: Preparation of co-milled powder: The co-milled powder is prepared by uniformly mixing fused magnesia powder, fused magnesia-zirconium powder, aluminum-silicon alloy powder, boron carbide and α-Al2O3 micro powder according to the mass fractions.

[0050] Step 2: Preparation of granular aggregate: The fused magnesia sand particles and fused magnesia zircon sand particles are uniformly mixed according to the mass fraction to obtain granular aggregate.

[0051] Step 3: Mixing: Dry mix the granular aggregate with a mixer for 1-3 minutes, then slowly add the binder and wet mix for 6-8 minutes, and finally add the co-milling powder and mix for 25-35 minutes to obtain the mixture.

[0052] Step 4: Molding: Press the mixture into shape on a 1200t electric screw press to obtain brick blanks, and let them cool naturally for 8 hours.

[0053] Step 5: Drying: Place the brick blanks in a drying kiln. The initial temperature upon entering the kiln is 60℃, and the bricks are dried at this temperature for at least 2 hours. The temperature is then increased to 120℃, and the bricks are dried at this temperature for at least 2 hours. The temperature is then increased to 150℃, and the bricks are dried at this temperature for at least 4 hours. The temperature is then increased to 180℃, and the bricks are dried at this temperature for at least 4 hours. The temperature is then increased to between 200℃ and 230℃, and the bricks are dried for at least 15 hours. The total drying time is at least 27 hours. After the bricks are removed from the kiln, qualified semi-finished products are selected.

[0054] Step Six: Stirring: The iron hoop is located in the middle, the weld of the iron hoop must not exceed 1mm, and the gap between the iron hoop and the sliding plate must not exceed 1mm.

[0055] Step 7: Grinding: Grind on a CNC vertical spindle rotary table surface grinder. The flatness of the working surface of the slide plate is less than 0.05mm. The moisture generated during the grinding process of the slide plate is dried using an infrared dryer.

[0056] Step 8: Apply a veneer, coat the surface, inspect and package the product to obtain the finished product.

[0057] This preparation method uses a non-firing process, which eliminates the firing stage of the sliding bricks, shortens the production cycle of the sliding bricks, and reduces production costs.

[0058] Specific implementation examples are given below.

[0059] Example 1

[0060] The preparation method of non-fired sliding plate bricks includes the following steps, and the various components and their mass fractions are shown in Table 1:

[0061] Step 1: Preparation of co-milled powder: The co-milled powder is prepared by uniformly mixing fused magnesia powder, fused magnesia-zirconium powder, aluminum-silicon alloy powder, boron carbide and α-Al2O3 micro powder according to the mass fractions.

[0062] Step 2: Preparation of granular aggregate: The fused magnesia sand particles and fused magnesia zircon sand particles are uniformly mixed according to the mass fraction to obtain granular aggregate.

[0063] Step 3: Mixing: Dry mix the granular aggregate with a mixer for 1-3 minutes, then slowly add the binder and wet mix for 6-8 minutes, and finally add the co-milling powder and mix for 25-35 minutes to obtain the mixture.

[0064] Step 4: Molding: Press the mixture into shape on a 1200t electric screw press to obtain brick blanks, and let them cool naturally for 8 hours.

[0065] Step 5: Drying: Place the brick blanks in a drying kiln. The initial temperature upon entering the kiln is 60℃, and the bricks are dried at this temperature for at least 2 hours. The temperature is then increased to 120℃, and the bricks are dried at this temperature for at least 2 hours. The temperature is then increased to 150℃, and the bricks are dried at this temperature for at least 4 hours. The temperature is then increased to 180℃, and the bricks are dried at this temperature for at least 4 hours. The temperature is then increased to between 200℃ and 230℃, and the bricks are dried for at least 15 hours. The total drying time is at least 27 hours. After the bricks are removed from the kiln, qualified semi-finished products are selected.

[0066] Step Six: Stirring: The iron hoop is located in the middle, the weld of the iron hoop must not exceed 1mm, and the gap between the iron hoop and the sliding plate must not exceed 1mm.

[0067] Step 7: Grinding: Grind on a CNC vertical spindle rotary table surface grinder. The flatness of the working surface of the slide plate is less than 0.05mm. The moisture generated during the grinding process of the slide plate is dried using an infrared dryer.

[0068] Step 8: Apply a veneer, coat the surface, inspect and package the product to obtain the finished product.

[0069] This preparation method uses a non-firing process, which eliminates the firing stage of the sliding bricks, shortens the production cycle of the sliding bricks, and reduces production costs.

[0070] Example 2

[0071] In this embodiment, the composition and mass fraction of the non-fired sliding plate bricks are as shown in Table 1, and the preparation method is the same as in Example 1.

[0072] Example 3

[0073] In this embodiment, the composition and mass fraction of the non-fired sliding plate bricks are as shown in Table 1, and the preparation method is the same as in Example 1.

[0074] Table 1. Mass parts of each component in unfired sliding plate bricks of Examples 1-3

[0075]

[0076] Table 2 Performance parameters of existing products and products in Examples 1-3

[0077]

[0078] Table 2 shows that the non-fired sliding plate bricks of this invention were tested on large steel ladles. After the test, the surface conditions of the low-carbon magnesium-zirconium-carbon non-fired sliding plate bricks and existing magnesium-carbon steel ladle sliding plate bricks were analyzed, including corrosion, roughening, and cracking. The service life was 1-2 cycles, and the average diameter expansion of the casting holes was 4mm, which is comparable to the corrosion efficiency of existing magnesium-carbon steel ladle sliding plates. During use, the non-fired sliding plate bricks of this invention showed good cracking performance on the lower sliding plate, with only radial micro-cracks in the casting holes. No abnormal corrosion of the casting holes or abnormal roughening of the surface was observed, thus demonstrating excellent corrosion resistance and thermal shock resistance.

[0079] The examples described herein are merely preferred embodiments of the invention and are not intended to limit the concept and scope of the invention. Any modifications and improvements made by those skilled in the art to the technical solutions of the invention without departing from the design concept of the invention should fall within the protection scope of the invention.

Claims

1. A non-fired sliding plate brick, characterized in that: It includes granular aggregate and co-ground powder, wherein the mass percentage of granular aggregate is 65% to 70%, the mass percentage of co-ground powder is 30% to 35%, and the total percentage of both is 100%. The composition of the granular aggregate and its mass percentage in the granular aggregate are: 55% to 60% fused magnesia sand particles and 40% to 45% fused magnesia zircon sand particles. The composition of the co-ground powder and its mass percentage in the unfired slide block brick are as follows: 10%–15% fused magnesia powder, 8%–12% fused magnesia-zirconium powder, 5%–10% α-Al2O3 micro powder, 5%–10% aluminum-silicon alloy powder and 1%–3% boron carbide powder.

2. The non-fired sliding plate brick according to claim 1, characterized in that: It also includes a binder, which is liquid aluminum dihydrogen phosphate, wherein the liquid aluminum dihydrogen phosphate contains: 9% ≥ Al2O3 content ≥ 7%, 34% ≥ P2O5 content ≥ 32%, and R2O content ≤ 0.12%, and the mass of the binder is 5% to 6% of the total mass of the granular aggregate and the co-ground powder.

3. The non-fired sliding plate brick according to claim 1, characterized in that: The fused magnesia particles have three particle sizes: 3-1 mm, 1-0.5 mm, and 0.5-0 mm. The mass fractions of each particle size are as follows: 10-15 parts of fused magnesia particles with a particle size of 3-1 mm, 8-12 parts of fused magnesia particles with a particle size of 1-0.5 mm, and 5-10 parts of fused magnesia particles with a particle size of 0.5-0 mm.

4. The non-fired sliding plate brick according to claim 3, characterized in that: The fused silica sand particles contain MgO content ≥ 96.3%, CaO content ≤ 1.5%, SiO2 content ≤ 1.3%, and the content of CaO+SiO2+Al2O3+Fe2O3 ≤ 3.4%.

5. The non-fired sliding plate brick according to claim 1, characterized in that: The fused magnesium zircon sand particles have three particle sizes: 3-1 mm, 1-0.5 mm, and 0.5-0 mm. The mass fractions of each particle size are as follows: 8-12 parts of fused magnesium zircon sand particles with a particle size of 3-1 mm, 8-12 parts of fused magnesium zircon sand particles with a particle size of 1-0.5 mm, and 5-10 parts of fused magnesium zircon sand particles with a particle size of 0.5-0 mm.

6. The non-fired sliding plate brick according to claim 5, characterized in that: The fused magnesium zircon sand particles contain the following contents: MgO content ≥90%, ZrO2 content ≥4%, SiO2 content ≤2.5%, Fe2O3 content ≤0.6%, and CaO content ≤1.2%.

7. A non-fired sliding plate brick according to any one of claims 1-6, characterized in that: The aluminum-silicon alloy powder contains: Al content ≥79.2%, active Al content ≥75.5%, Fe content ≤0.2%, Al+Si content ≥99.2%, and Cu content ≤0.1%.

8. A non-fired sliding plate brick according to any one of claims 1-6, characterized in that: In the boron carbide: the content of B4C is ≥95%, B 总 The content of C is ≥75%. 总 The content of free carbon is ≥21%, the content of B2O3 is ≤0.15%, the content of free carbon is ≤3%, and the content of free carbon is ≤0.3%.

9. A non-fired sliding plate brick according to any one of claims 1-6, characterized in that: The α-Al2O3 micro powder contains: Al2O3 content ≥ 99.5%, SiO2 content ≤ 0.1%, Fe2O3 content ≤ 0.8%, and R2O content ≤ 0.2%.

10. A method for preparing non-fired sliding plate bricks according to any one of claims 1-9, characterized in that, Includes the following steps: Step 1: Preparation of co-milled powder: The co-milled powder is prepared by uniformly mixing fused magnesia powder, fused magnesia-zirconium powder, aluminum-silicon alloy powder, boron carbide and α-Al2O3 micro powder according to the mass parts. Step 2: Preparation of granular aggregate: The fused magnesia sand particles and fused magnesia zircon sand particles are uniformly mixed according to the mass fraction to obtain granular aggregate; Step 3: Mixing: Dry mix the granular aggregate for 1-3 minutes, then add the binder and wet mix for 6-8 minutes, and finally add the co-ground powder and mix for 25-35 minutes to obtain the mixture; Step 4: Molding: Press the mixture into shape to obtain brick blanks, and let them cool naturally for 8 hours; Step 5: Drying: Place the brick blanks in a drying kiln. The initial temperature upon entering the kiln is 60℃, and drying at this temperature should last for at least 2 hours. Increase the temperature to 120℃ and dry for at least 2 hours. Increase the temperature to 150℃ and dry for at least 4 hours. Increase the temperature to 180℃ and dry for at least 4 hours. Increase the temperature to between 200 and 230℃ and dry for at least 15 hours. The total drying time should be at least 27 hours. After removing the bricks from the kiln, select qualified semi-finished products. Step Six: Applying a hoop; Step 7: Grinding; Step 8: Apply a veneer, coat the surface, inspect and package the product to obtain the finished product.

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