Preparation process of high-air-temperature-resistant pipeline brick

Abstract

The invention belongs to the technical field of high-temperature-resistant bricks. The invention provides a preparation process of a high-air-temperature-resistant pipeline brick, which comprises the following steps: S1, putting 64-67 parts by weight of sintered mullite, 8-10 parts by weight of white corundum, 6-8 parts by weight of andalusite, 1-2 parts by weight of silicon dioxide micro powder, 5-6 parts by weight of aluminum oxide micro powder, 3-4 parts by weight of cobalt-doped sodium titanate and 2.5-3.5 parts by weight of plasma activated yttrium oxide into a mixer for dry mixing, 4-5 parts of water is added for wet mixing, and a mixture is obtained; s2, the mixture obtained in S1 is put into a mold to be pressed, then the mixture is taken out and naturally dried for 36-48 h, then the mixture is put into a dryer to be dried, and a green brick is obtained; and S3, putting the green brick obtained in the S2 into a kiln, calcining, and cooling to obtain the high-air-temperature-resistant pipeline brick. The apparent porosity of the prepared pipeline brick is effectively reduced, the alkali corrosion resistance of the pipeline brick is improved, and the service life is prolonged.

Description

Technical Field

[0001] The invention belongs to the technical field of high-temperature resistant bricks, and particularly relates to a preparation process of high-wind-temperature resistant pipe bricks. Background Art

[0002] As the core equipment in blast furnace ironmaking systems, the hot blast furnace's hot blast duct lining material (duct bricks) must withstand temperatures exceeding 1200°C and periodic thermal stress shocks. Currently, high-alumina bricks and clay bricks are widely used in the industry. Their complementary material properties balance refractory and thermal insulation requirements, achieving efficient and durable hot blast delivery.

[0003] Hot air contains alkaline substances such as K2O and Na2O. When hot air is transported by a hot blast furnace, its hot air ducts operate for long periods of time at high temperatures (1200-1300°C) and are corroded by alkaline substances. Due to the pores in the pipe bricks of the hot air ducts, alkaline oxides in the hot air can penetrate into the pipe bricks through the pores and react with the alumina component of the pipe bricks to form low-melting-point minerals such as nepheline. This destroys the crystal structure and causes the surface to melt and flake off, which in turn reduces the pipe bricks' resistance to alkali corrosion and shortens their service life. Summary of the Invention

[0004] In order to solve the problems existing in the background technology, the present invention provides a preparation process of high wind temperature resistant pipe bricks, which can effectively reduce the apparent porosity of the prepared pipe bricks, improve their alkali corrosion resistance, and extend their service life.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: A preparation process of high wind temperature resistant pipe bricks comprises the following steps: S1. Put 64-67 parts of sintered mullite, 8-10 parts of white corundum, 6-8 parts of andalusite, 1-2 parts of silica powder, 5-6 parts of alumina powder, 3-4 parts of cobalt-doped sodium titanate and 2.5-3.5 parts of plasma-activated yttrium oxide into a mixer, dry mix them, and then add 4-5 parts of water for wet mixing to obtain a mixture; S2, placing the mixture obtained in S1 into a mold for pressing, then taking it out and drying it naturally for 36-48 hours, and then placing it in a dryer for drying to obtain a brick; S3. Place the bricks obtained in S2 into a kiln for calcination and cooling to obtain the high wind and temperature resistant pipe bricks.

[0006] Furthermore, the plasma-activated yttrium oxide is prepared by treating nano-yttrium oxide powder with Ar / O2 mixed plasma activation.

[0007] Furthermore, the preparation method of the cobalt-doped sodium titanate is as follows: A1. Add 150-165 g of titanium tetrachloride to 554-562 g of a 22% hydrochloric acid solution to obtain a first solution; add the first solution dropwise into distilled water to obtain a precipitate, add aqueous ammonia while stirring, adjust the pH to 7, and then filter, wash, and calcine the precipitate to obtain anatase titanium oxide; A2. Take 0.5 g of anatase titanium oxide obtained in A1, 0.074 g of cobalt chloride hexahydrate, and 50 mL of 2 mol / L sodium hydroxide solution, place them in an autoclave, stir for 2-3 h, and then seal and store to obtain a solid; A3. Wash and air-dry the solid obtained in A2 to obtain cobalt-doped sodium titanate.

[0008] Furthermore, in A1, the calcination temperature is 300-350° C., and the calcination time is 2-3 h.

[0009] Furthermore, in A2, the sealed storage temperature is 140-148°C, and the sealed storage time is 12-24 hours.

[0010] Furthermore, in A3, the specific operation of washing is: the solid matter is washed three times each with 0.1 mol / L hydrochloric acid solution, distilled water and anhydrous ethanol.

[0011] Furthermore, in S1, the mixer is a conical mixer; dry mixing is performed at 25-30 r / min for 3-5 min; and wet mixing is performed at 12-15 r / min for 5-7 min.

[0012] Furthermore, in S2, the drying temperature in the dryer is 110±5°C, and the drying time is 22-25h.

[0013] Furthermore, in S3, the calcination temperature is 1550°C-1650°C, and the calcination time is 13-15 hours.

[0014] This application has the following beneficial effects: 1. In the preparation of plasma activated yttrium oxide of the present invention, Ar / O2 mixed plasma is used to treat nano yttrium oxide powder to form oxygen vacancy defects on its surface. Oxygen vacancies reduce Y 3+ Diffusion barrier, improves its migration rate, accelerates migration and fills the pores generated by the high-temperature decomposition of cobalt-doped sodium titanate, and reacts with alumina in the brick body through high-temperature diffusion to form yttrium aluminum garnet. On the one hand, its crystal growth can close the interconnected pores with a pore size greater than 5μm, directly reducing the apparent porosity; on the other hand, the thermal expansion coefficient of yttrium aluminum garnet is similar to that of mullite, which alleviates the lattice distortion stress caused by the decomposition of sodium titanate after cobalt doping, inhibits the expansion of microcracks, and indirectly reduces the apparent porosity; it prevents alkaline oxides from penetrating into the interior of the pipe brick through pores / cracks, thereby improving the pipe brick's resistance to alkali corrosion.

[0015] 2. Plasma-activated yttrium oxide can react with alkaline steam (K2O / Na2O) to generate yttrium silicate (melting point 1770℃) and yttrium aluminate (melting point 1950℃), which covers the surface of the pipe brick to form a dense layer, reduces the apparent porosity, blocks the contact between alkaline substances and Al2O3 / SiO2 of the pipe brick, and improves the alkali corrosion resistance of the pipe brick.

[0016] 3. Cobalt doping reduces the decomposition temperature of sodium titanate to 800°C, making the pore generation stage earlier than the reaction period of nano yttrium oxide powder, reserving a time window for subsequent filling; the decomposition product cobalt oxide acts as a mineralizer to reduce the reaction activation energy of nano yttrium oxide powder and alumina to synthesize yttrium aluminum garnet, accelerate the kinetic process of nano yttrium oxide powder and alumina to synthesize yttrium aluminum garnet, so that it can more effectively inhibit the expansion of microcracks and reduce the apparent porosity; thereby preventing alkaline oxides from penetrating into the interior of the pipe brick through cracks, and improving the alkali corrosion resistance of the pipe brick. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 , a comparative trend chart of the apparent porosity test data of the pipe bricks prepared in Examples 1 to 3 and Comparative Examples 1 to 4 in the test examples of the present invention. DETAILED DESCRIPTION

[0018] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0019] Unless otherwise specified, the raw materials used in the examples and comparative examples of the present application are all commercially available.

[0020] Example 1: (I) Preparation of plasma-activated yttrium oxide, which is prepared by treating nano-yttrium oxide powder with Ar / O2 mixed plasma activation. The specific preparation method is as follows: B1. Place nano-yttrium oxide powder (particle size ≤ 100 nm) in anhydrous ethanol and ultrasonically disperse it for 30 minutes (power 300 W) to form a uniform suspension (solid content 10 wt%). After vacuum filtration, dehydrate in an 80°C drying oven for 12 hours to obtain a loose, non-agglomerated pretreated powder.

[0021] B2, using parallel plate electrode plasma equipment (electrode spacing 50mm), pre-evacuate the chamber to ≤10 -3The substrate is a porous alumina tray (5μm pore size) to ensure a monolayer of pretreated powder (≤1mm thick). The working gas is an Ar / O₂ mixture (85% Ar, 15% O₂), with a gas flow rate of 50sccm, a chamber pressure of 50Pa, and an RF power of 300W (13.56MHz frequency) to avoid excessive power that could cause powder melting. The treatment time is 10 minutes; exceeding this time may cause surface flaking. The substrate temperature is water-cooled and controlled to ≤80°C to prevent nanoparticle sintering. High-energy electrons (5-15eV) impinge on the Y₂O₃ surface, dislodging lattice oxygen to form oxygen vacancies (VO). O₂ dissociates to produce reactive oxygen atoms that fill some of the vacancies, creating a controllable defect concentration.

[0022] B3. After activation, high-purity N2 is introduced into the cavity to atmospheric pressure, and the powder is transferred to a nitrogen-filled glove box (O2 ≤ 0.1 ppm). It is sealed and stored in a moisture-proof aluminum bag for later use to prevent oxygen vacancies from being deactivated due to adsorption of water vapor.

[0023] (2) Preparation of cobalt-doped sodium titanate. The specific preparation method is as follows: A1. Add 160g of titanium tetrachloride (TiCl4) to 560g of 22% hydrochloric acid solution and stir at 320 rpm until completely dissolved to obtain the first solution. Add the first solution dropwise to 500mL of distilled water at a rate of approximately 3mL / min while maintaining vigorous stirring (800 rpm) and an ice-water bath (0-5°C) to prevent localized oversaturation and uneven precipitation. After the addition is complete, continue stirring for 30 minutes to ensure complete hydrolysis and form a white precipitate.

[0024] Add 25% ammonia dropwise to the precipitate to adjust the pH to 7.0 while maintaining stirring at 500 rpm. The pH adjustment should be slow, taking approximately 10 minutes, to avoid a vigorous reaction that could cause the precipitate to agglomerate. Then, collect the precipitate by suction filtration using a Buchner funnel.

[0025] The precipitate was washed four times with 100 mL of deionized water each time, stirring for 5 minutes to remove chloride ions. It was then washed once with 50 mL of anhydrous ethanol to dehydrate and reduce the risk of agglomeration during subsequent calcination. The washed precipitate was then placed in a crucible and heated to 320°C at a rate of 5°C / min in an air atmosphere. The temperature was maintained for 2.5 hours (the calcination furnace must be preheated to 100°C). The temperature was then cooled to room temperature at a rate of 2°C / min to obtain a white anatase titanium oxide powder.

[0026] A2: Place 0.5 g of anatase titanium oxide from A1, 0.074 g of cobalt chloride hexahydrate (CoCl2·6H2O), and 50 mL of 2 mol / L sodium hydroxide solution in a Teflon-lined autoclave. Stir at 400 rpm for 2 hours at room temperature to ensure a homogeneous suspension. Then, purge with nitrogen for 2 minutes to remove residual oxygen and prevent the formation of oxidative impurities. Seal the container and heat it to 145°C at 3°C / min. Hold the temperature for 20 hours (temperature fluctuation <±2°C). Cool the container naturally to room temperature before opening the autoclave to prevent pressure surges that could cause material rupture. Upon opening the autoclave, a blue-green solid was obtained, indicating successful cobalt doping.

[0027] A3. Wash the solid obtained in A2 with 0.1 mol / L hydrochloric acid solution, distilled water, and anhydrous ethanol three times each. Then, air-dry in a fume hood (25 ± 5°C, approximately 35% humidity) for 36 hours. The final product is a light blue powder, which is cobalt-doped sodium titanate.

[0028] (3) A process for preparing high-wind-temperature-resistant pipe bricks, comprising the following steps: S1. Place 65 parts by weight of sintered mullite, 9 parts of white corundum, 7 parts of andalusite, 1.5 parts of silica powder, 5.5 parts of alumina powder, 3.5 parts of cobalt-doped sodium titanate, and 3 parts of plasma-activated yttrium oxide into a conical mixer and dry-mix at 28 rpm for 4 minutes, pausing every 1 minute for 30 seconds to scrape the wall to avoid stratification. Add 4.5 parts of water and wet-mix at 14 rpm for 6 minutes to obtain a mixture.

[0029] Before use, sintered mullite was crushed to a particle size ≤0.5 mm, with approximately 60% of the particles being 0.1-0.3 mm and approximately 40% being 0.3-0.5 mm, to enhance particle size density. Cobalt-doped sodium titanate was ball-milled (ball-to-material ratio 5:1, ethanol medium, 300 rpm, 2 h) to reduce agglomeration and ensure a particle size D50 ≤2 μm. White corundum (0.1-1 mm) was purchased from Shandong Yingge Ceramics Sisha Taishan Abrasive Co., Ltd. Andalusite (<1 mm) was purchased from Henan Yuchen Refractory Materials Co., Ltd. Silica micropowder (400 mesh) was purchased from Hunan Qilu New Materials Technology Co., Ltd. Alumina micropowder (260 mesh) was purchased from Jiangfeng Mineral Products Processing Plant in Lingshou County.

[0030] S2. Place the mixture obtained in S1 into a mold and press it in both directions using a hydraulic press (pressure 85 MPa), holding the pressure for 30 seconds. Spray the inner wall of the mold with zinc stearate release agent. After pressing, let it rest for 2 hours before demolding to reduce cracking. After removal, naturally dry it for 40 hours at a temperature of 25±3°C and a humidity of 50-60%. Then, dry it in a dryer, heating it at a rate of 5°C / hour to 110°C, and drying it for 24 hours to obtain the green bricks.

[0031] S3. Place the bricks obtained in S2 into a kiln for calcination at a temperature of 1600° C. for 14 hours, and cool to obtain high-wind-temperature-resistant pipe bricks.

[0032] Specifically, the oxidizing atmosphere (air flow rate 10m 3 / h), and heated to 600℃ at a heating rate of 3℃ / min; then nitrogen (5m 3 / h) to prevent cobalt oxidation, the temperature was raised to 1200°C at a rate of 5°C / min; then, in a weak reducing atmosphere (CO content 1%), the temperature was raised to 1600°C at a rate of 2°C / min and held at that temperature for 14 hours. The product was then slowly cooled to 800°C at a rate of 2°C / min to prevent stress cracking caused by mullite phase transformation; then, it was naturally cooled to 200°C before being discharged from the kiln.

[0033] Example 2: This example differs from Example 1 in that a process for preparing a high-temperature-resistant pipe brick comprises the following steps: S1. Place 64 parts of sintered mullite, 8 parts of white corundum, 6 parts of andalusite, 1 part of silica powder, 5 parts of alumina powder, 3 parts of cobalt-doped sodium titanate, and 2.5 parts of plasma-activated yttrium oxide into a conical mixer, dry-mix at 25 rpm for 5 min, then add 4 parts of water and wet-mix at 12 rpm for 7 min to obtain a mixture.

[0034] S2. Place the mixture obtained in S1 into a mold for pressing, then take it out and dry it naturally for 36 hours, and then place it in a dryer for drying. The drying temperature in the dryer is 110°C and the drying time is 22 hours to obtain bricks.

[0035] S3. Place the bricks obtained in S2 into a kiln for calcination at a temperature of 1550°C for 15 hours, and cool to obtain high-wind-temperature-resistant pipe bricks.

[0036] Example 3: This example differs from Example 1 in that a process for preparing a high-temperature-resistant pipe brick comprises the following steps: S1. Put 67 parts of sintered mullite, 10 parts of white corundum, 8 parts of andalusite, 2 parts of silica powder, 6 parts of alumina powder, 4 parts of cobalt-doped sodium titanate and 3.5 parts of plasma-activated yttrium oxide into a conical mixer, dry-mix at 30 r / min for 3 min, then add 5 parts of water and wet-mix at 15 r / min for 5 min to obtain a mixture.

[0037] S2. Place the mixture obtained in S1 into a mold for pressing, then take it out and dry it naturally for 48 hours, and then place it in a dryer for drying. The drying temperature in the dryer is 110°C and the drying time is 25 hours to obtain a brick.

[0038] S3. Place the bricks obtained in S2 into a kiln for calcination at a temperature of 1650°C for 13 hours, and cool to obtain high-wind-temperature-resistant pipe bricks.

[0039] Comparative Example 1: The difference between this comparative example and Example 1 is that in the preparation of high wind temperature resistant pipe bricks, cobalt-doped sodium titanate and plasma-activated yttrium oxide are replaced by sintered mullite.

[0040] Comparative Example 2: The difference between this comparative example and Example 1 is that in the preparation of high wind temperature resistant pipe bricks, plasma activated yttrium oxide is replaced by sintered mullite.

[0041] Comparative Example 3: The difference between this comparative example and Example 1 is that: in the preparation of high wind temperature resistant pipe bricks, cobalt-doped sodium titanate is replaced by sintered mullite; and plasma-activated yttrium oxide is replaced by nano yttrium oxide powder.

[0042] Comparative Example 4: The difference between this comparative example and Example 1 is that in the preparation of high wind temperature resistant pipe bricks, plasma activated yttrium oxide is replaced by nano yttrium oxide powder.

[0043] Test Example: The apparent porosity test data of the pipe bricks obtained in Examples 1 to 3 and Comparative Examples 1 to 4 are shown in Table 1.

[0044] Table 1. Test data of experimental example

[0045] Result analysis: Analyze Example 1-Example 3 and combine the data in Table 1 and Figure 1 It can be seen that the apparent porosity of the pipe bricks prepared by the present invention (Example 1-Example 3) is as low as below 13.5%.

[0046] Analyze Example 1 and Comparative Examples 1-4 and combine the data in Table 1 and Figure 1 Specifically, by comparing Comparative Example 1 and Comparative Example 2, it can be seen that compared with Comparative Example 1, Comparative Example 2 introduces cobalt-doped sodium titanate alone, and the apparent porosity of the resulting pipe brick is increased from 15.3% (Comparative Example 1) to 15.9% (Comparative Example 2). This shows that the introduction of cobalt-doped sodium titanate alone will cause the apparent porosity of the resulting pipe brick to increase instead of decrease. This is mainly because, after cobalt doping, sodium titanate decomposes into Na2O and Co-TiO2 composite phases at high temperatures (>1270°C), and sodium oxide (Na2O) volatilizes to form pores, which increases the apparent porosity; Co 2+ The ions occupying TiO2 lattice sites cause lattice distortion and generate microcracks, which further increase the apparent porosity by increasing the open pore volume.

[0047] Comparing Comparative Examples 1 and 3, we can see that the addition of nano-yttrium oxide powder alone in Comparative Example 3 reduced the apparent porosity of the resulting pipe brick from 15.3% (Comparative Example 1) to 14.5% (Comparative Example 3). This indicates that the introduction of nano-yttrium oxide powder alone can reduce the apparent porosity of the resulting pipe brick. This is primarily because nano-yttrium oxide powder reacts with alkaline vapor (K2O / Na2O) to form yttrium silicate (melting point 1770°C) and yttrium aluminate (melting point 1950°C), which cover the surface of the pipe brick to form a dense layer, reducing the apparent porosity.

[0048] Comparison with Comparative Example 4 shows that the simultaneous introduction of nano-yttrium oxide powder and cobalt-doped sodium titanate can produce a synergistic effect, synergistically reducing the apparent porosity of the resulting pipe brick. This is mainly because the nano-yttrium oxide powder can migrate and fill the pores generated by the high-temperature decomposition of cobalt-doped sodium titanate, reacting with the alumina in the brick body through high-temperature diffusion to form yttrium aluminum garnet. On the one hand, its crystal growth can close the interconnected pores with a pore size greater than 5μm, directly reducing the apparent porosity; on the other hand, the thermal expansion coefficient of yttrium aluminum garnet is similar to that of mullite, which alleviates the lattice distortion stress caused by the decomposition of cobalt titanate, inhibits the propagation of microcracks, and indirectly reduces the apparent porosity. Cobalt doping reduces the decomposition temperature of sodium titanate to 800°C, making the pore generation stage earlier than the reaction period of nano-yttrium oxide powder, reserving a time window for subsequent filling; the decomposition product cobalt oxide acts as a mineralizer, reducing the reaction activation energy of nano-yttrium oxide powder and alumina to synthesize yttrium aluminum garnet, accelerating the kinetic process of the synthesis of yttrium aluminum garnet by nano-yttrium oxide powder and alumina, so that it can more efficiently inhibit the expansion of microcracks and reduce the apparent porosity.

[0049] By comparison with Example 1, it can be seen that the synergistic effect is further enhanced by preparing the plasma-activated yttrium oxide of the present invention from nano-yttrium oxide powder and then introducing it together with cobalt-doped sodium titanate, and the apparent porosity of the obtained pipe brick is further reduced. This is mainly because, in the preparation of plasma-activated yttrium oxide, Ar / O2 mixed plasma is used to treat the nano-yttrium oxide powder, forming oxygen vacancy defects on its surface, and oxygen vacancies reduce Y 3+ Diffusion barrier, increasing its migration rate, accelerating migration and filling into the pores generated by the high-temperature decomposition of cobalt-doped sodium titanate; oxygen vacancies can also promote the reactivity of Y2O3 and Al2O3, lowering the formation temperature of yttrium aluminum garnet, sealing the pores in advance, and improving the sealing effect.

[0050] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A process for preparing high-temperature resistant pipe bricks, characterized in that: The following steps are involved: S1. Put 64-67 parts of sintered mullite, 8-10 parts of white corundum, 6-8 parts of andalusite, 1-2 parts of silica powder, 5-6 parts of alumina powder, 3-4 parts of cobalt-doped sodium titanate and 2.5-3.5 parts of plasma-activated yttrium oxide into a mixer, dry mix them, and then add 4-5 parts of water for wet mixing to obtain a mixture; S2, placing the mixture obtained in S1 into a mold for pressing, then taking it out and drying it naturally for 36-48 hours, and then placing it in a dryer for drying to obtain a brick; S3. Place the bricks obtained in S2 into a kiln for calcination and cooling to obtain the high wind and temperature resistant pipe bricks.

2. The preparation process of the high wind temperature resistant pipe brick according to claim 1, characterized in that: The plasma-activated yttrium oxide is prepared by subjecting nano-yttrium oxide powder to an Ar / O2 mixed plasma activation treatment.

3. The preparation process of high wind temperature resistant pipe brick according to claim 1, characterized in that: The preparation method of the cobalt-doped sodium titanate is as follows: A1. Add 150-165 g of titanium tetrachloride to 554-562 g of a 22% hydrochloric acid solution to obtain a first solution; add the first solution dropwise into distilled water to obtain a precipitate, add ammonia water while stirring, adjust the pH to 7, and then filter, wash, and calcine the precipitate to obtain anatase titanium oxide; A2. Take 0.5 g of anatase titanium oxide obtained in A1, 0.074 g of cobalt chloride hexahydrate, and 50 mL of 2 mol / L sodium hydroxide solution, place them in an autoclave, stir for 2-3 h, and then seal and store to obtain a solid; A3. Wash and air-dry the solid obtained in A2 to obtain cobalt-doped sodium titanate.

4. The preparation process of the high wind temperature resistant pipe brick according to claim 3, characterized in that: In A1, the calcination temperature is 300-350°C and the calcination time is 2-3h.

5. The process for preparing high wind and temperature resistant pipe bricks according to claim 3, characterized in that: In A2, the sealed storage temperature is 140-148°C and the sealed storage time is 12-24 hours.

6. The process for preparing high wind and temperature resistant pipe bricks according to claim 3, characterized in that: In A3, the specific washing operation is: the solid matter is washed three times with 0.1 mol / L hydrochloric acid solution, distilled water and anhydrous ethanol respectively.

7. The process for preparing high wind and temperature resistant pipe bricks according to claim 1, characterized in that: In S1, the mixer is a conical mixer; dry mixing is performed at 25-30 r / min for 3-5 min; and wet mixing is performed at 12-15 r / min for 5-7 min.

8. The process for preparing high wind and temperature resistant pipe bricks according to claim 1, characterized in that: In S2, the drying temperature in the dryer is 110±5°C, and the drying time is 22-25h.

9. The process for preparing high wind and temperature resistant pipe bricks according to claim 1, characterized in that: In S3, the calcination temperature is 1550° C.-1650° C., and the calcination time is 13-15 hours.

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