Wear-resistant refractory material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of functional materials, and particularly relates to a wear-resistant refractory material as well as a preparation method and application thereof. According to the wear-resistant refractory material provided by the invention, the black silicon carbide and the compact fused white corundum are used as aggregates, the green silicon carbide micro powder, the aluminum oxide micro powder and the zirconite micro powder are used as base materials, the aluminum chromium phosphate and the nano aluminum sol are used as binding agents, the coagulant and the anti-stripping fibers are added, and the raw materials are naturally cured at normal temperature, so that the curing speed is high; chemical bonding occurs under the medium temperature condition, and ceramic complex phase bonding occurs under the high temperature condition, so that the wear-resistant refractory material provided by the invention is high in strength, resistant to coal cinder scouring under the high-temperature and high-pressure conditions and long in service life.

Description

Technical Field

[0001] The present invention belongs to the technical field of functional materials, and in particular relates to a wear-resistant refractory material and a preparation method and application thereof. Background Art

[0002] When a pulverized coal or water-coal slurry water-cooled wall gasifier is in operation, the furnace is exposed to high temperature (1350-1500°C), high pressure (3-5 MPa) and a strong reducing atmosphere (CO, H2, H2S, etc.), and the furnace temperature fluctuates greatly. At the same time, it faces high-speed erosion of substances such as coal slag. These factors will cause serious erosion and damage to the lining of the water-cooled wall, and therefore put forward higher performance requirements for the lining material.

[0003] The existing water-cooled wall lining is mainly made of aluminum phosphate, aluminum chromium phosphate, pure calcium aluminate cement and alumina powder as binders, and silicon carbide, fused white corundum, chromium corundum, zirconium corundum and polypropylene fiber as main raw materials. It has low strength at medium and high temperatures and cannot withstand the long-term erosion of high-temperature and high-pressure coal slag. It has a short service life and requires regular maintenance, which seriously affects the utilization rate of the gasifier. Summary of the Invention

[0004] The purpose of the present invention is to provide a wear-resistant refractory material and a preparation method and application thereof. The wear-resistant refractory material provided by the present invention has high strength, is resistant to coal slag erosion under high temperature and high pressure conditions, and has a long service life.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a wear-resistant refractory material, which is made of the following raw materials in parts by mass:

[0007] 50-65 parts of black silicon carbide, 7-20 parts of green silicon carbide powder, 1-11 parts of dense fused white corundum, 1-10 parts of zircon powder, 1-5 parts of alumina powder, 6-10 parts of aluminum chromium phosphate, 1.2-6 parts of nano aluminum sol, 0.5-3 parts of coagulant and 0.5-4.5 parts of anti-stripping fiber.

[0008] Preferably, the black silicon carbide is spherical in shape; and the particle size of the black silicon carbide is not greater than 3 mm.

[0009] Preferably, the green silicon carbide micropowder is spherical in shape; and the particle size of the green silicon carbide micropowder is 45 to 75 microns.

[0010] Preferably, the particle size of the dense fused white corundum is 30 to 50 microns.

[0011] Preferably, the alumina powder is α-alumina powder; the particle size of the alumina powder is 2 to 3 microns.

[0012] Preferably, the coagulant comprises one or both of aluminum hydroxide fine powder and magnesium oxide fine powder; the particle size of the aluminum hydroxide fine powder is 2 to 3 microns; the particle size of the magnesium oxide fine powder is 3 to 5 microns.

[0013] Preferably, the anti-stripping fibers include one or both of low-temperature decomposable fibers and high-temperature resistant fibers; the anti-stripping fibers have a diameter of 5 to 30 microns and a length of 2 to 5 millimeters.

[0014] The present invention also provides a method for preparing the wear-resistant refractory material according to the above scheme, comprising the following steps:

[0015] Black silicon carbide, green silicon carbide powder, dense fused white corundum, zircon powder, alumina powder, aluminum chromium phosphate, nano aluminum sol, coagulant and anti-stripping fiber are mixed and then molded, solidified and heat-treated in sequence to obtain the wear-resistant refractory material.

[0016] Preferably, the heat treatment is a staged heat treatment; the staged heat treatment includes a first heating, a first heat treatment, a second heating and a second heat treatment performed in sequence; the first heating rate is 7 to 9°C / h; the temperature of the first heat treatment is 100 to 120°C, and the insulation time is 6 to 8 hours; the second heating rate is 7 to 9°C / h; the temperature of the second heat treatment is 215 to 245°C, and the insulation time is 6 to 8 hours.

[0017] The present invention also provides the use of the wear-resistant refractory material described in the above scheme or the wear-resistant refractory material obtained by the preparation method described in the above scheme in coal chemical equipment or petrochemical equipment.

[0018] The present invention provides a wear-resistant refractory material. The wear-resistant refractory material provided by the present invention has high strength, is resistant to coal slag erosion under high temperature and high pressure conditions, has a long service life, has small heating line changes, and is chemically stable. The mechanism involved is as follows:

[0019] The wear-resistant refractory material provided by the present invention uses black silicon carbide and dense fused white corundum as aggregates, green silicon carbide micropowder, alumina micropowder and zircon micropowder as base materials, aluminum chromium phosphate and nano-aluminum sol as binders, and is added with a coagulant and anti-stripping fiber. The above raw materials undergo natural solidification at room temperature with a fast solidification speed. During operation, chemical bonding occurs under medium temperature conditions (950-1200°C) and ceramic composite bonding occurs under high temperature conditions (1201-1500°C). The specific mechanism under medium and high temperature conditions is as follows:

[0020] The anti-stripping fibers rapidly decompose and volatilize upon heating, forming nano-scale capillaries. Free water and structural water in the raw material slurry can be quickly discharged through the capillaries, preventing the slurry from bursting and shortening the shedding furnace drying time. The aluminum chromium phosphate is dehydrated, concentrated, and polymerized upon heating, producing chemical bonding. The highly active alumina powder reacts with zircon powder and binder to form dense, short rod-shaped zirconium mullite and spherical aluminum chromium phosphate grains. The nano-aluminum sol begins to transform into high-temperature α-Al2O3 crystals, undergoing multi-polymerization and solid-phase reaction to form polycrystalline composite phase crystals, which fill or encapsulate the black silicon carbide and dense fused white corundum, forming a wear-resistant refractory material with a three-dimensional network structure. This improves the density and strength of the wear-resistant refractory material, reduces its apparent porosity, enhances its erosion resistance and wear resistance, and significantly improves its resistance to coal slag erosion and fly ash scouring. When used in water-cooled wall linings, the service life is extended by more than three months compared to existing water-cooled wall linings.

[0021] The present invention also provides a method for preparing the wear-resistant refractory material of the above scheme. The preparation method provided by the present invention has simple steps, convenient operation, good feasibility and good economic benefits.

[0022] The present invention also provides for the use of the wear-resistant refractory material described in the above embodiment, or the wear-resistant refractory material obtained by the preparation method described in the above embodiment, in coal chemical or petrochemical equipment. The wear-resistant refractory material provided by the present invention can be used in gasifiers, such as pulverized coal gasifiers and improved water-coal slurry gasifiers, as a lining material for the water-cooled walls of gasifiers. It can also be used around burners or in wall boxes. It has excellent wear resistance, a long service life, reduces maintenance frequency, and improves the overall utilization rate of the gasifier. DETAILED DESCRIPTION

[0023] The present invention provides a wear-resistant refractory material, which is made of the following raw materials in parts by mass:

[0024] 50-65 parts of black silicon carbide, 7-20 parts of green silicon carbide powder, 1-11 parts of dense fused white corundum, 1-10 parts of zircon powder, 1-5 parts of alumina powder, 6-10 parts of aluminum chromium phosphate, 1.2-6 parts of nano aluminum sol, 0.5-3 parts of coagulant and 0.5-4.5 parts of anti-stripping fiber.

[0025] Calculated by weight, the raw materials of the wear-resistant refractory material provided by the present invention include 50 to 65 parts of black silicon carbide, specifically 55 parts or 60 parts.

[0026] In the present invention, the black silicon carbide can be spherical in shape; the particle size of the black silicon carbide can be no greater than 3 mm, specifically 2.5 mm, 2 mm, 1.5 mm, 1 mm, or 0.5 mm. The spherical particles used in the present invention provide low resistance and easy sliding during construction, ensuring the density of the water wall lining and facilitating construction.

[0027] In the present invention, the black silicon carbide can be black hexagonal spherical silicon carbide; the purity of the black silicon carbide can be 98.5% (special grade). The black silicon carbide used in the present invention has strong resistance to high-temperature oxidation, high density, a Mohs hardness of 9.5, excellent wear resistance, and a heat transfer coefficient of up to 120-150 MPa, making it an ideal high-temperature resistant material for gasifier water-cooled walls.

[0028] Based on the mass fraction of the black silicon carbide, the raw materials of the wear-resistant refractory material provided by the present invention include 7 to 20 parts of green silicon carbide powder, specifically 9 parts, 14 parts or 17 parts.

[0029] In the present invention, the shape of the green silicon carbide micropowder can be spherical; the particle size of the green silicon carbide micropowder can be 45 to 75 microns, specifically 55 microns or 65 microns, preferably 45 microns and 75 microns; when the particle size of the green silicon carbide micropowder is 45 microns (denoted as small micropowder) and 75 microns (denoted as large micropowder), the weight ratio of the small micropowder to the large micropowder can be 2:3.

[0030] In the present invention, the green silicon carbide powder can have a purity of over 99%. Green silicon carbide powder has higher purity and hardness than black silicon carbide and can be orderly filled into the gaps between black silicon carbide and dense fused white corundum, forming a "densely packed" structure that ensures the strength of the wear-resistant and refractory material.

[0031] Based on the mass fraction of the black silicon carbide, the raw materials of the wear-resistant refractory material provided by the present invention include 1 to 11 parts of dense fused white corundum, specifically 2 parts, 4 parts, 6 parts, 8 parts or 10 parts.

[0032] In the present invention, the particle size of the dense fused white corundum may be 30 to 50 microns, specifically 35 microns, 40 microns or 45 microns.

[0033] Based on the mass fraction of the black silicon carbide, the raw materials of the wear-resistant refractory material provided by the present invention include 1 to 10 parts of zircon powder, specifically 3 parts, 5 parts, 7 parts or 9 parts.

[0034] In the present invention, the particle size of the zircon powder may be 20 to 35 microns, specifically 25 microns or 30 microns.

[0035] Based on the mass fraction of the black silicon carbide, the raw material of the wear-resistant refractory material provided by the present invention may include 1 to 5 parts of α-alumina powder, specifically 2 parts, 3 parts or 4 parts.

[0036] In the present invention, the alumina powder may be α-alumina powder; the particle size of the alumina powder may be 2 to 3 microns, specifically 2.2 microns, 2.5 microns or 2.8 microns.

[0037] Based on the mass fraction of the black silicon carbide, the raw materials of the wear-resistant refractory material provided by the present invention include 6 to 10 parts of chromium aluminum phosphate, specifically 7 parts, 8 parts or 9 parts.

[0038] In the present invention, the content of Al2O3 and Cr2O3 in the aluminum chromium phosphate may be no less than 35 wt%, specifically 40 wt%, 45 wt% or 50 wt%.

[0039] In the present invention, the aluminum chromium phosphate can be Al-35 aluminum chromium phosphate. After solidification, aluminum chromium phosphate has a strong bonding strength, forming a P2O5-Al2O3-Cr2O3 complex that wraps around the surface of other raw materials, firmly bonding them together. P2O5 easily decomposes at high temperatures, which can lower the melting point of oxides and the decomposition temperature of non-oxides.

[0040] Based on the mass fraction of the black silicon carbide, the raw materials of the wear-resistant refractory material provided by the present invention include 1.2 to 6 parts of nano-aluminum sol, specifically 1.5 parts, 2 parts, 3 parts, 4 parts or 5 parts.

[0041] In the present invention, the Al2O3 content in the nano-alumina sol can be no less than 30wt%, specifically 35wt%, 40wt%, 45wt%, or 50wt%. The nano-alumina sol can be nano-alumina sol MAL-2050. Nano-alumina sol forms a stable crystalline phase under high-temperature conditions, offering superior heat resistance to aluminum chromium phosphate, but exhibits slightly inferior bonding strength at low temperatures. The present invention utilizes a composite binder to complement the properties of aluminum chromium phosphate and nano-alumina sol. Under high-temperature conditions, the aluminum chromium phosphate and nano-alumina sol dehydrate and concentrate, resulting in a corresponding increase in strength.

[0042] Based on the mass fraction of the black silicon carbide, the raw materials of the wear-resistant refractory material provided by the present invention include 0.5 to 3 parts of a coagulant, specifically 1 part or 2 parts.

[0043] In the present invention, the coagulant can include one or both of aluminum hydroxide powder and magnesium oxide powder; the aluminum hydroxide powder can be highly active γ-type aluminum hydroxide powder; the particle size of the aluminum hydroxide powder can be 2 to 3 microns, specifically 2.5 microns; the magnesium oxide powder can be dead-burned magnesium oxide powder; the particle size of the magnesium oxide powder can be 3 to 5 microns, specifically 4 microns. Dead-burned magnesium oxide powder has a good coagulant effect at room temperature, reacting with the acidic substances in the colloid of the wear-resistant and refractory material, causing the colloid to begin to solidify; the γ-type aluminum hydroxide powder has a large specific surface area and reacts with the colloid above 60°C, promoting the solidification of the colloid and avoiding the presence of the low-melting-point dead-burned magnesium oxide powder.

[0044] Based on the mass fraction of the black silicon carbide, the raw materials of the wear-resistant refractory material provided by the present invention include 0.5 to 4.5 parts of anti-stripping fiber, specifically 1 part, 2 parts, 3 parts or 4 parts.

[0045] In the present invention, the anti-stripping fiber may have a diameter of 5 to 30 microns, specifically 7 microns, 8 microns, 10 microns, 15 microns, 20 microns or 25 microns, and a length of 2 to 5 millimeters, specifically 3 millimeters or 4 microns.

[0046] In the present invention, the anti-stripping fiber may include low-temperature decomposable fiber and high-temperature resistant fiber; the low-temperature decomposable fiber may be a vinylon ultra-short fiber, specifically C-70 vinylon ultra-short fiber; the high-temperature resistant fiber may be a high-temperature resistant ceramic alumina short fiber; the Al2O3 content in the high-temperature resistant ceramic alumina short fiber may be not less than 90wt%.

[0047] The raw materials of the wear-resistant refractory material provided by the present invention adopt the above-mentioned gradation and dosage to achieve optimal accumulation of raw material particles, thereby further improving density and mechanical strength.

[0048] The present invention also provides a method for preparing the wear-resistant refractory material according to the above scheme, comprising the following steps:

[0049] Black silicon carbide, green silicon carbide powder, dense fused white corundum, zircon powder, alumina powder, aluminum chromium phosphate, nano aluminum sol, coagulant and anti-stripping fiber are mixed and then molded, solidified and heat-treated in sequence to obtain the wear-resistant refractory material.

[0050] The present invention mixes black silicon carbide, green silicon carbide powder, dense fused white corundum, zircon powder, alumina powder, aluminum chromium phosphate, nano-aluminum sol, a coagulant, and anti-stripping fiber (referred to as a first mixing process) to obtain a mixed product. In the present invention, the first mixing process can be stirring; the stirring mixing can be performed at a speed of 70 to 110 rpm, for a mixing time of more than 3 minutes, and the stirring mixing device can be a planetary stainless steel stirrer.

[0051] After mixing, the present invention sequentially shapes, solidifies and heat-treats the mixed product to obtain the wear-resistant refractory material. In the present invention, the shaping may be: coating the mixed product on the surface of the water-cooled wall of the gasifier.

[0052] In the present invention, the curing temperature can be 5 to 35°C, specifically 15°C or 25°C, the air humidity can be less than 50%, specifically 40% or 30%, and the curing time can be 12 to 24 hours, specifically 15 hours, 18 hours or 21 hours; the curing atmosphere can be air; and the curing method can be natural curing.

[0053] In the present invention, the heat treatment may be performed in the form of a baking furnace; the heat treatment may be a staged heat treatment; the staged heat treatment may include a first temperature rise, a first heat treatment, a second temperature rise, and a second heat treatment performed in sequence.

[0054] In the present invention, the first heating rate can be 7-9°C / h, specifically 8°C / h; the temperature of the first heat treatment can be 100-120°C, specifically 110°C, and the holding time can be 6-8 hours, specifically 7 hours; the second heating rate can be 7-9°C / h, specifically 8°C / h; the temperature of the second heat treatment can be 215-245°C, specifically 220°C, 230°C or 240°C, and the holding time can be 6-8 hours, specifically 7 hours. In the present invention, during the above-mentioned heat treatment process, when the temperature reaches 60-110°C, the anti-stripping fiber quickly decomposes and volatilizes, forming nano-scale capillaries, and free water and structural water can be quickly discharged from the capillaries, preventing the slurry from bursting, and the shedding oven time is shortened by 30% compared to the original.

[0055] The present invention also provides the use of the wear-resistant refractory material described in the above scheme or the wear-resistant refractory material obtained by the preparation method described in the above scheme in coal chemical equipment or petrochemical equipment.

[0056] In the present invention, the application method may include the following steps: mixing the raw materials of the wear-resistant refractory material and ramming them on the water-cooled wall of the gasifier to perform solidification and heat treatment in sequence.

[0057] In the present invention, the ramming can be completed within 30 minutes after mixing; and the ramming can also include compacting and leveling with a trowel and a micro vibrator.

[0058] In the present invention, other parameters of the application method can be the same as those of the preparation method of the wear-resistant refractory material, and will not be repeated here. The present invention removes all free water in the water-cooled wall lining through heat treatment, so that the gasifier can operate normally.

[0059] In order to further illustrate the present invention, the scheme of the present invention is described in detail below with reference to the embodiments, but they should not be understood as limiting the scope of protection of the present invention.

[0060] In a specific embodiment of the present invention, the mass of the raw materials can be g or kg; the purity of the green silicon carbide micropowder is 99.0%; the binder is prepared from Al-35 aluminum chromium phosphate and nano-aluminum sol MAL-2050; the coagulant is γ-type aluminum hydroxide micropowder; the Al2O3 content of the high-temperature resistant ceramic alumina short fiber is 90%, the diameter is 20 to 30 microns, and the length is 2 to 4 mm.

[0061] Example 1

[0062] Weigh 56 parts of special black silicon carbide, 17 parts of green silicon carbide powder, 8 parts of dense fused white corundum, 3 parts of zircon powder, 4 parts of α-alumina powder, 8 parts of aluminum chromium phosphate, 2 parts of nano aluminum sol, 0.5 parts of coagulant and 1.5 parts of anti-stripping fiber.

[0063] The weighed raw materials (excluding the binder) were mixed in a planetary mixer at 80 rpm. Mix dry for 1 minute, then slowly add the binder and mix for 2 minutes until the mixture reaches a dough-like or putty-like consistency to form the ramming material. The ramming material was manually filled and compacted using a mold, and the surface of the ramming material lining was smoothed using a vibrating trowel. The ramming material was then rammed onto the gasifier water-cooled wall within 30 minutes. The material was naturally cured for 24 hours at a temperature of 15-25°C and an air humidity of less than 50% to concentrate, dehydrate, and solidify the binder. When the gasifier was heated to 70°C, the C-70 vinylon ultra-short fibers began to decompose, leaving moisture-draining channels in the ramming material lining. This accelerated the escape of water vapor and other gases from the lining and reduced thermal stress caused by thermal expansion. Utilizing heat from the water-cooling pipes in the gasifier's newly opened furnace wall, the temperature was raised at 7°C / hour to 110°C, held for 8 hours, and then further raised to 230°C and held for 6 hours. As the furnace temperature rises, the binder continues to concentrate, dehydrate, and undergo polymerization reactions, generating high-temperature-resistant, high-strength composite crystals. The surface of the silicon carbide particles oxidizes to form a SiO2 film layer, which reacts with the alumina powder in the ramming material to form mullite, which wraps around the surface of the black silicon carbide, creating a chemical-ceramic bond and resulting in a wear-resistant refractory material, designated BCS-75.

[0064] Example 2

[0065] Weigh 51 parts of special black silicon carbide, 18 parts of green silicon carbide powder, 7 parts of dense fused white corundum, 7 parts of zircon powder, 3 parts of α-alumina powder, 9 parts of aluminum chromium phosphate, 2.5 parts of nano aluminum sol, 0.5 parts of coagulant and 2.0 parts of anti-stripping fiber.

[0066] The weighed raw materials (excluding the binder) were stirred and mixed in a planetary mixer at 80 rpm. Two-thirds of the total binder was added and stirred for 2 minutes. The remaining one-third was then slowly added and stirred to obtain a ramming material. The ramming material was manually filled using a mold and repeatedly rammed and compacted with a plastic hammer. The surface of the ramming material lining was smoothed using a non-metallic polishing block. The resulting ramming material was rammed onto the water-cooled wall of the gasifier within 30 minutes. It was naturally cured for 24 hours at a temperature of 15-25°C and an air humidity of less than 50% to concentrate, dehydrate, and solidify the binder. When the gasifier was heated to 70°C, the C-70 vinylon ultra-short fibers began to decompose, leaving microporous moisture-draining channels in the ramming material lining. Using the heat from the water-cooling pipes of the gasifier's newly opened furnace wall, the temperature was raised to 110°C at a rate of 7°C / h, held for 8 hours, and then further raised to 230°C and held for 6 hours to obtain a wear-resistant and refractory material.

[0067] Example 3

[0068] Weigh 49 parts of special black silicon carbide, 19 parts of green silicon carbide powder, 9 parts of dense fused white corundum, 5 parts of zircon powder, 4.5 parts of α-alumina powder, 10 parts of aluminum chromium phosphate, 1.2 parts of nano aluminum sol, 0.8 parts of coagulant and 1.5 parts of anti-stripping fiber.

[0069] The weighed raw materials (excluding the binder) were stirred and mixed in a planetary mixer at a speed of 90 rpm. The mixture was mixed in a dry state for 2 minutes, and the binder was added and stirred for 3 minutes until it reached a dough or putty-like state to obtain a ramming material. The ramming material was filled and compacted manually using a mold, and mechanically worked using an air hammer. The surface of the ramming material lining was smoothed using a wooden smoothing block. The ramming material was rammed onto the water-cooled wall of the gasifier within 25 minutes. It was naturally cured for 15 hours at a temperature of 20-30°C and an air humidity of less than 45%. The temperature was then raised to 110°C at a rate of 8°C / h using the heat in the water-cooling pipes of the gasifier wall just after it was opened. The temperature was then kept at this temperature for 7 hours. The temperature was then further raised to 250°C and kept at this temperature for 8 hours to obtain a wear-resistant and refractory material.

[0070] Example 4

[0071] Weigh 65 parts of special black silicon carbide, 20 parts of green silicon carbide powder, 1 part of dense fused white corundum, 2 parts of zircon powder, 1 part of α-alumina powder, 7 parts of aluminum chromium phosphate, 2 parts of nano aluminum sol, 1 part of coagulant and 1 part of anti-stripping fiber.

[0072] The weighed raw materials (excluding the binder) were stirred and mixed in a planetary mixer at 70 rpm for 1.5 minutes. The binder was then added and stirred for 2 minutes. The stirring speed was increased to 100 rpm, and a coagulant was added and stirred for 2 minutes until the mixture reached a dough or putty-like consistency. The ramming material was manually filled and compacted using a mold, and the surface of the ramming material lining was smoothed using wooden polishing blocks. The ramming material was rammed onto the water-cooled wall of the gasifier within 30 minutes. The material was naturally cured for 18 hours at 5°C and with an air humidity of less than 50%. The material was then heated to 110°C at a rate of 8°C / h using the heat from the water-cooling pipes of the gasifier wall immediately after it was opened. The temperature was then held at this temperature for 7 hours. The temperature was then further raised to 230°C and held at this temperature for another 7 hours to obtain a wear-resistant and refractory material designated BCS-85.

[0073] Test Example 1

[0074] The physical parameters, chemical composition, and wear performance of the wear-resistant refractory materials prepared in Examples 1 and 4 of the present invention were tested. CN102417360A was used as a control. According to the YB / T 5200 method for preparing amorphous refractory samples, the ramming material was made into a 160×40×40 mm test block. The room temperature wear amount was tested according to the standard specification. The results are shown in Table 1.

[0075] Table 1 Performance test of wear-resistant refractory materials prepared in Examples 1 and 4 and the control group

[0076]

[0077] As can be seen from Table 1, the embodiment of the present invention uses black silicon carbide and dense fused white corundum as aggregates, green silicon carbide micropowder, alumina micropowder and zircon micropowder as base materials, aluminum chromium phosphate and nano-aluminum sol as binders, and adds a coagulant and anti-stripping fiber. Compared with the control group, the present invention gives the material a higher working temperature through nano-aluminum sol, improves its bonding ability under high temperature conditions, and makes it more able to withstand the erosion of high-temperature and high-pressure coal slag; aluminum chromium phosphate will decompose and produce P2O5 gas during the heating process. The present invention can also achieve good bonding performance by using a smaller amount of aluminum chromium phosphate, achieving the dual effects of improving material performance and protecting the ecological environment.

[0078] The present invention further improves the wear-resistant refractory material's resistance to high-temperature, high-pressure coal slag erosion by combining specific amounts of black silicon carbide with green silicon carbide micropowder and zircon micropowder. The present invention utilizes granular materials of varying particle sizes, along with micropowder and nano-glue, to achieve an optimal particle size combination, resulting in a "densely packed" structure. The bulk density of the raw material is significantly increased, the apparent porosity on the surface is correspondingly reduced, and the rate of change of the heating line at 1100°C is 30% to 50% lower than that of the control group. The present invention improves the material's high-temperature anti-stripping performance through the use of high-temperature resistant fibers. Low-temperature decomposable fibers begin to decompose at 70°C, leaving micropores for moisture drainage, facilitating the rapid discharge of free water. The heat treatment temperature is halved compared to the control group, which not only extends the device's operating time but also saves heat treatment costs.

[0079] Application Example 1

[0080] The wear-resistant refractory material prepared in Example 1 of the present invention was put to practical use, using the same method as in Example 1, in the water-cooled walls of the Shell gasifier at the 300kt / a ammonia synthesis unit of Guizhou Tianfu Chemical Co., Ltd. The results showed that the wear-resistant refractory material of the present invention achieved a service life of 15,000 hours in the water-cooled walls of the Shell gasifier at the 300kt / a ammonia synthesis unit of Guizhou Tianfu Chemical Co., Ltd., representing a service life increase of more than 25% compared to the original material.

[0081] Application Example 2

[0082] The wear-resistant refractory material prepared in Example 1 of the present invention was put to practical use, using the same method as in Example 1, on the water-cooled walls of the Hangtian-brand gasifier at the Henan Energy Puyang Zhongyuan Dahua Methanol Division. The results showed that the wear-resistant refractory material of the present invention achieved a service life of 13,000 hours in the water-cooled walls of the Hangtian-brand gasifier at the Henan Energy Puyang Zhongyuan Dahua Methanol Division, representing a service life increase of over 25% compared to the original design.

[0083] Test Example 2

[0084] The wear-resistant refractory materials prepared in Examples 1 and 4 of the present invention were tested in terms of physical parameters, mechanical properties, thermal properties, and chemical composition. Commercially available products were used as controls. According to the YB / T 5200 method for preparing amorphous refractory samples, the ramming materials were made into 160×40×40 mm test blocks. The room temperature wear amount was tested according to standard specifications. The results are shown in Table 2.

[0085] Table 2 Performance comparison of wear-resistant refractory materials prepared in Examples 1 and 4 and the control group

[0086]

[0087]

[0088] It can be seen from Table 2 that the wear-resistant refractory material of the present invention has a strength increased by more than 20% compared with the imported material, a heating line change rate of only about 10% of that of the imported material, and good volume stability at high temperatures.

[0089] It can be seen from the above embodiments that the wear-resistant refractory material provided by the present invention has high strength, is resistant to coal slag erosion under high temperature and high pressure conditions, has good thermal stability and a long service life.

[0090] Although the above embodiment provides a detailed description of the present invention, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the scope of protection of the present invention.

Claims

1. A wear-resistant refractory material, characterized in that: The invention is made of the following raw materials in parts by weight: 50-65 parts of black silicon carbide, 7-20 parts of green silicon carbide powder, 1-11 parts of dense fused white corundum, 1-10 parts of zircon powder, 1-5 parts of alumina powder, 6-10 parts of aluminum chromium phosphate, 1.2-6 parts of nano aluminum sol, 0.5-3 parts of coagulant and 0.5-4.5 parts of anti-stripping fiber.

2. The wear-resistant refractory material according to claim 1, characterized in that: The black silicon carbide is spherical in shape; and the particle size of the black silicon carbide is no greater than 3 mm.

3. The wear-resistant refractory material according to claim 1 or 2, characterized in that: The green silicon carbide micropowder is spherical in shape and has a particle size of 45 to 75 microns.

4. The wear-resistant refractory material according to claim 1, characterized in that: The particle size of the dense fused white corundum is 30 to 50 microns.

5. The wear-resistant refractory material according to claim 1 or 4, characterized in that: The alumina powder is α-alumina powder; the particle size of the alumina powder is 2 to 3 microns.

6. The wear-resistant refractory material according to claim 1, characterized in that: The coagulant comprises one or both of aluminum hydroxide micropowder and magnesium oxide micropowder; the particle size of the aluminum hydroxide micropowder is 2 to 3 microns; the particle size of the magnesium oxide micropowder is 3 to 5 microns.

7. The wear-resistant refractory material according to claim 1 or 6, characterized in that: The anti-stripping fibers include one or both of low-temperature decomposable fibers and high-temperature resistant fibers; the anti-stripping fibers have a diameter of 5 to 30 microns and a length of 2 to 5 millimeters.

8. The method for preparing the wear-resistant refractory material according to any one of claims 1 to 7, characterized in that: The following steps are involved: Black silicon carbide, green silicon carbide powder, dense fused white corundum, zircon powder, alumina powder, aluminum chromium phosphate, nano aluminum sol, coagulant and anti-stripping fiber are mixed and then molded, solidified and heat-treated in sequence to obtain the wear-resistant refractory material.

9. The preparation method according to claim 8, characterized in that The heat treatment is a staged heat treatment; the staged heat treatment includes a first heating, a first heat treatment, a second heating and a second heat treatment performed in sequence; the first heating rate is 7 to 9°C / h; the temperature of the first heat treatment is 100 to 120°C, and the holding time is 6 to 8 hours; the second heating rate is 7 to 9°C / h; the temperature of the second heat treatment is 215 to 245°C, and the holding time is 6 to 8 hours.

10. Use of the wear-resistant refractory material according to any one of claims 1 to 7 or the wear-resistant refractory material obtained by the preparation method according to any one of claims 8 to 9 in coal chemical equipment or petrochemical equipment.

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