A repair material for a self-flowing blast furnace tapping trough, its preparation method and use

Abstract

The present invention discloses a self-flowing repair material for blast furnace tapping troughs, its preparation method and uses. The repair material comprises the following raw materials in parts by weight: 40-60 parts of a base material, 5-8 parts of a firing promoter, 10-20 parts of graphite powder, 15-30 parts of a binder, 4-8 parts of organic fiber, 0.05-1 part of an expansion agent, and 0.01-1 part of a hardening promoter. The repair material of the present invention has good fluidity, can enter deep into cracks, and it is difficult to ensure that all small gaps are filled with gunning material. In addition, the repair body formed by the repair material has good bonding with the original matrix and can be used for a long time.

Description

Technical Field

[0001] The invention relates to the technical field of materials, and in particular to a repairing material for a gravity-flow blast furnace tapping channel, a preparation method and application thereof. Background Art

[0002] With the continuous progress of blast furnace metallurgical technology, blast furnaces are gradually developing towards large-scale and long-life. In today's increasingly fierce market competition, longer tapping time and higher molten iron flow rate are the inevitable development direction of the tapping ditch. However, the tapping ditch of a blast furnace is prone to damage after long-term use.

[0003] At present, most blast furnace iron troughs are made of Al 2 O 3 -SiC-C refractory material is used as the lining. Since the iron tapping trough is eroded by molten iron for a long time, the refractory lining is easily damaged. In order to increase the service life of the iron tapping trough and reduce the steelmaking cost, the damaged position of the iron tapping trough is usually hot-repaired so that it can continue to be used.

[0004] Japanese Patent Sho 54-56619 discloses a "blast furnace iron channel gunning material". The finished gunning material contains 5-15% SiC, 2-10% SiO 2 The remainder is Al 2 O 3 The above technical scheme mainly has the following two problems: 1. Since the damaged shape of the refractory lining is irregular, the gunning material itself has no fluidity and cannot enter the deep cracks. It is difficult to ensure that all the small gaps are filled with gunning material when using the gunning machine to repair the damaged position, which makes it difficult to form an effective repair; 2. The repair material contains water, which will produce water vapor during high-temperature sintering, thereby reducing the bonding force between the repair body and the original matrix.

[0005] In order to solve the above problems, the conventional practice in this field is to increase the strength of the castable to extend the service life of the iron ditch. For example, Chinese patent CN202010488415.3 discloses a blast furnace iron ditch with mullite fiber toughened Al 2 O 3-SiC-C refractory castable, which uses 55-65 parts by mass of brown corundum, 20-30 parts by mass of silicon carbide, 6-10 parts by mass of α-alumina powder, 2-4 parts by mass of pure calcium aluminate cement as raw materials, 0.3-0.9 parts by mass of mullite fiber, 0.5-1.5 parts by mass of silicon powder, 1-3 parts by mass of spherical asphalt and 0.05-0.15 parts by mass of water reducing agent as additives, but it can only meet the requirements of casting and still cannot be used as a repair material. Chinese patent CN1059414 discloses a self-flowing hot repair material and its manufacturing method, which has poor fluidity and easy shrinkage and solidification problems.

[0006] Therefore, there is an urgent need for a self-flowing special repair material for a blast furnace tapping ditch. Summary of the invention

[0007] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a repairing material for a gravity-flow blast furnace tapping channel and a preparation method thereof.

[0008] The iron outlet groove of a blast furnace is easily damaged after long-term use. The existing technology generally uses high-strength castables to cast the iron outlet groove in order to extend the service life of the iron outlet groove, and there are few methods that can directly repair the damaged position of the iron outlet groove; the existing method that can directly repair the iron outlet groove is to use gunning materials to repair the damaged position, but this method is difficult to effectively repair deep gaps, resulting in poor repair effect, poor bonding between the repair body and the original matrix, and cannot be used for a long time.

[0009] The first aspect of the present invention protects a repair material for a self-flowing blast furnace tapping channel, comprising the following raw materials in parts by weight:

[0010]

[0011] The repair material for the blast furnace iron outlet groove of the present application is a solid-liquid mixture, which has very low fluidity at room temperature. The ambient temperature during hot repair is high, the material has good high-temperature fluidity, and the amount used each time is small. It can perform rapid self-flowing hot repairs on the penetrating cracks formed locally in the iron outlet groove or the cracks generated at the connection parts of the grooves, thereby extending the service life of the lining refractory material.

[0012] In certain embodiments of the present application, the base material is selected from one or more of alumina powder, magnesia and attapulgite.

[0013] Preferably, the particle size of the alumina powder is less than 2 μm.

[0014] Preferably, based on the total mass of the alumina powder, the Al 2 O 3 Content ≥98.5wt%, K 2O and Na 2 The total content of O is ≤0.05wt%. 2 O 3 , K 2 O and Na 2 The detection method of O refers to "GB / T21114-2019 Refractory Material X-ray Fluorescence Spectrochemical Analysis Cast Glass Sheet Method".

[0015] Preferably, the particle size of the magnesia is 1 to 3 mm.

[0016] Preferably, the magnesia sand includes magnesia sand with a particle size of 1 to 2.2 mm and magnesia sand with a particle size of 2.2 to 3 mm.

[0017] More preferably, the mass ratio of the magnesia with a particle size of 1 to 2.2 mm to the magnesia with a particle size of 2.2 to 3 mm is (60 to 80): (20 to 40).

[0018] Preferably, based on the total mass of the magnesia, the content of MgO in the magnesia is greater than 94.3wt%, and the content of CaO, SiO 2 , Fe 2 O 3 The total content of MgO, CaO, SiO in the magnesia of the present application is ≤5.7wt%. 2 , Fe 2 O 3 The detection method is referred to GB T2273-1997 Sintered Magnesia. Preferably, the rod crystal length of the attapulgite is 1 to 5 μm and the diameter is 20 to 70 nm.

[0019] Preferably, the base material is a mixture of alumina powder, magnesia and attapulgite.

[0020] More preferably, the mass ratio of the alumina powder, magnesia and attapulgite is (12-18): (8-12): (20-30).

[0021] In certain embodiments of the present application, the sintering promoter is selected from silicon carbide powder.

[0022] Preferably, the particle size of the silicon carbide powder is 325 mesh.

[0023] Preferably, based on the total mass of the silicon carbide powder, the content of SiC in the silicon carbide powder is ≥ 98 wt %.

[0024] In certain embodiments of the present application, the graphite powder has a particle size of 20 to 75 μm. Preferably, the graphite powder is selected from flake graphite and artificial electrode graphite.

[0025] More preferably, the mass ratio of the flake graphite to the artificial electrode graphite is 1:1.

[0026] In certain embodiments of the present application, the binder includes a phenolic resin and an organic solvent.

[0027] Preferably, the organic solvent is selected from one or more of ethanol, propanol, glycerol and ethylene glycol.

[0028] Preferably, the weight ratio of the phenolic resin to the organic solvent is (25-50):(50-75).

[0029] In certain embodiments of the present application, the organic fiber is selected from polyethylene staple fibers or polypropylene staple fibers.

[0030] Preferably, the length of the organic fiber is 1 to 8 mm, and the linear density of the organic fiber is 1 to 2.5 Ttex.

[0031] In certain embodiments of the present application, the expansion agent is selected from one or both of kyanite and quartz.

[0032] Preferably, the expansion agent is selected from kyanite.

[0033] More preferably, the particle size of the kyanite is 35 mesh to 65 mesh, Al 2 O 3 Content ≥59wt%, Fe 2 O 3 Content ≤1.0wt%.

[0034] In certain embodiments of the present application, the hardening accelerator is selected from one or more of aluminum hydroxide, talc, and magnesium oxide.

[0035] The second aspect of the present invention protects a method for preparing a repairing material for a self-flowing blast furnace tapping channel as described above, comprising the following steps:

[0036] Mixing the base material and the graphite powder in parts by weight to obtain a first premix;

[0037] The first premix, the organic fiber and the binder are mixed for a second time to obtain a second premix;

[0038] The second premix, the sintering agent, the expansion agent and the hardening agent are mixed for the third time to obtain the repairing material for the iron outlet channel of the self-flowing blast furnace.

[0039] In certain embodiments of the present application, the first mixing time is 5 to 15 minutes.

[0040] In certain embodiments of the present application, the second mixing time is 30 to 45 minutes.

[0041] In certain embodiments of the present application, the third mixing time is 5 to 10 minutes.

[0042] A third aspect of the present invention protects the use of the repairing material for a gravity-flow blast furnace tapping channel as described above in a blast furnace tapping channel.

[0043] First, remove the residue on the surface of the blast furnace tapping channel that needs to be repaired, and then throw the repair material in the packaging bag directly to the part that needs to be repaired at high temperature. The repair material will enter the deep of the crack by itself to complete the repair, and it will be sintered after 15-30 minutes.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] 1) The present invention adopts alumina powder, magnesia and attapulgite as base materials. Alumina powder is mainly used to improve strength. Magnesia can play a skeleton role in the sintering process, which can improve the sintering process and improve the permeability of the material layer. At the same time, it can optimize the sintering quality of the repair material and improve the fluidity, thereby improving the bonding strength and compressive and flexural strength of the sintered layer, and improving the anti-scouring ability; the rod crystal length of attapulgite is 1-5 microns, the diameter is between 20-70 nanometers, and it has a unique three-dimensional space chain structure and a special needle and rod-shaped crystal structure, so it has unusual colloid and adsorption properties, has certain thickening properties, stable chemical properties, and strong bonding force; the base material makes the repair material have higher strength and scouring resistance, which can ensure long-term use after repair.

[0046] 2) The present invention adds silicon carbide powder and graphite powder. Silicon carbide powder as a sintering promoter can reduce the sintering time as much as possible and improve the high-temperature strength of the material; graphite powder can form a carbon skeleton after carbonization and sintering, thereby enabling other components to jointly form a high-strength repair body.

[0047] 3) The present invention uses thermoplastic, non-water-soluble phenolic resin and organic solution as binders, which not only avoids moisture in the repair material, but also the phenolic resin has thermoplasticity, which can improve plasticity and enhance fluidity as the temperature rises. Phenolic resin decomposes at about 350-600°C as the temperature rises, so the sintering time is short and can be completed within 15-30 minutes. After the phenolic resin decomposes, its residual carbon content can reach 50-60%, forming a carbon chain network structure at high temperature, improving the sintering strength and anti-scouring and anti-erosion capabilities.

[0048] 4) The present invention also adds organic fiber, expansion agent and hardening accelerator. The organic fiber mainly prevents solid-liquid separation and improves product viscosity. At the same time, it can be quickly melted during high-temperature sintering, which helps to improve high-temperature fluidity. The addition of the expansion agent can prevent the material from shrinking during the sintering process and avoid the separation of the repair body from the original matrix. The hardening accelerator can make the repair material solidify quickly after sintering, reduce the sintering molding time, and improve the strength of the repair body.

[0049] 5) The preparation process of the present invention is simple and easy to use, and is suitable for large-scale promotion and application. DETAILED DESCRIPTION

[0050] After a lot of exploration and experiments, the inventors have found a solid-liquid mixture, that is, a self-flowing blast furnace tapping channel repair material. It has very low fluidity at room temperature and high fluidity at high temperature. When it is placed on the crack of the blast furnace tapping channel, it can quickly self-flow to repair, and the formed repair body has good adhesion with the original matrix and high strength, which prolongs the service life of the blast furnace tapping channel.

[0051] The first aspect of the present invention protects a repair material for a self-flowing blast furnace tapping channel, comprising the following raw materials in parts by weight:

[0052]

[0053]

[0054] The repair material for the self-flowing blast furnace iron channel of the present application has a flow value of about 160-170mm at room temperature and a flow value of more than 290mm at 1000°C. It has a compressive strength of more than 40MPa and a flexural strength of more than 14MPa. It has low shrinkage and fast curing, and the formed repair body has a strong bonding force with the original matrix.

[0055] In the repair material of the present invention, the weight of the base material can be 40-60 parts, 40-48 parts, 46-54 parts, 52-56 parts, 54-60 parts by weight. In some embodiments, the base material is selected from one or more of alumina powder, magnesia, and attapulgite. In some specific embodiments, the base material is a mixture of alumina powder, magnesia and attapulgite, and the mass ratio of alumina powder, magnesia and attapulgite is (12-18): (8-12): (20-30). Alumina powder is mainly used to improve strength; magnesia sand can play a role of skeleton in the sintering process, which can improve the sintering process, improve the air permeability of the material layer, and optimize the sintering quality of the repair material and improve the fluidity, thereby improving the bonding strength and compressive and flexural strength of the sintered layer, and improving the anti-scouring ability; attapulgite has a unique three-dimensional chain structure and a special needle and rod-shaped crystal structure, so it has unusual colloid and adsorption properties, has a certain thickening property, stable chemical properties, and strong bonding force; alumina powder, magnesia sand and attapulgite as base materials make the repair material have higher strength and anti-scouring effect, which can ensure long-term use after repair. In a specific embodiment, the mass ratio of alumina powder, magnesia sand and attapulgite in the base material is 12:8:20, 15:10:25, 18:12:30; the weight of the base material is 40 parts, 50 parts and 60 parts.

[0056] In some embodiments, the particle size of the aluminum oxide powder is less than 2 μm. 2 O 3 Content ≥98.5wt%, K 2 O and Na 2 The total content of O is ≤0.05wt%. Alumina has a porous structure and a high specific surface area; its microporous surface has properties such as adsorption performance, surface activity, and excellent thermal stability. 2 O 3 , K 2 O and Na 2 The detection method of O refers to "GB / T 21114-2019 Refractory Materials X-ray Fluorescence Spectrochemical Analysis Cast Glass Sheet Method".

[0057] In some embodiments, the particle size of the magnesia is 1 to 3 mm. Wherein, the magnesia includes magnesia with a particle size of 1 to 2.2 mm and magnesia with a particle size of 2.2 to 3 mm. Preferably, the mass ratio of the magnesia with a particle size of 1 to 2.2 mm and the magnesia with a particle size of 2.2 to 3 mm is (60 to 80): (20 to 40). Using magnesia of different particle sizes for grading can fill more gaps, making the material denser, thereby improving its durability and stability. Preferably, based on the total mass of the magnesia, the content of MgO in the magnesia is >94.3wt%, and the content of CaO, SiO 2 and Fe 2 O 3 The total content of MgO, CaO, SiO in the magnesia of the present application is ≤5.7wt%. 2 and Fe 2 O 3 The detection method refers to GB T 2273-1997 Sintered Magnesia. In a specific embodiment, the mass ratio of magnesia with a particle size of 1 to 2.2 mm to magnesia with a particle size of 2.2 to 3 mm is 70:30.

[0058] In some embodiments, the rod crystal length of the attapulgite is 1 to 5 μm and the diameter is 20 to 70 nm. The rod crystal length of the attapulgite is 1 to 5 microns and the diameter is between 20 and 70 nanometers. It has a unique three-dimensional chain structure and a special needle and rod-shaped crystal structure, so it has unusual colloid and adsorption properties, certain thickening properties, stable chemical properties, and strong bonding force.

[0059] In the repair material described in the present invention, the weight of the sintering agent can be 5-8 parts, 5-6.4 parts, 5.8-7.1 parts, 6.7-7.6 parts, and 7.4-8 parts by weight. In some embodiments, the binder is selected from silicon carbide powder, and the particle size of the silicon carbide powder is 325 mesh; based on the total mass of the silicon carbide powder, the content of SiC in the silicon carbide powder is ≥98wt%. Silicon carbide powder as a sintering agent can reduce the sintering time as much as possible and improve the high temperature strength of the material. In a specific embodiment, the sintering agent is silicon carbide powder, and the particle size is 0.05-1mm; the weight parts are 7 parts, 7 parts and 5 parts.

[0060] In the repair material of the present invention, the weight of the graphite powder can be 10-20 parts, 10-16 parts, 14-18 parts, 16-20 parts by weight. In some embodiments, the particle size of the graphite powder is 20-75 μm, and the graphite powder is selected from one or both of flake graphite and artificial electrode graphite. Preferably, it is a mixture of flake graphite and artificial electrode graphite, and the mass ratio of the flake graphite to the artificial electrode graphite is (0.5-1):1. After carbonization and sintering, the graphite powder can form a carbon skeleton, so that other components can form a high-strength repair body together; flake graphite, which is shaped like fish phosphorus, belongs to the hexagonal crystal system, has a layered structure, is thin and has good toughness, has excellent physical and chemical properties, has extremely high refractory properties, and can form a fine "buffer zone" between the refractory grains and silicon carbide powder to absorb thermal stress. In a specific embodiment, the mass ratio of flake graphite to artificial electrode graphite is 1:1, the particle size of graphite powder is 0.2-0.8 mm, and the weight portions are 20 parts, 15 parts, and 10 parts.

[0061] In the repair material described in the present invention, the weight of the binder can be 15-30 parts, 10-19 parts, 16-27 parts, 19-28 parts, and 22-30 parts by weight. In some embodiments, the binder includes phenolic resin and an organic solvent. The organic solvent is selected from one or more of ethanol, propanol, glycerol and ethylene glycol; the weight ratio of the phenolic resin to the organic solvent is (25-50): (50-75). The phenolic resin in the present application has thermoplasticity, and its plasticity can be improved and its fluidity can be enhanced as the temperature rises. Phenolic resin decomposes at about 350-600°C as the temperature rises, so the sintering time is short and sintering can be completed within 15-30 minutes. After the phenolic resin is decomposed, its residual carbon content can reach 50-60%, and a carbon chain network structure is formed at high temperature to improve the sintering strength and the ability to resist scouring and erosion. In a specific embodiment, the organic solvent is ethanol, the mass ratios of the phenolic resin and the organic solvent are 12:12, 11:10 and 10:10; and the weight proportions of the binder are 24 parts, 24 parts and 20 parts.

[0062] In the repair material described in the present invention, the weight of the organic fiber can be 4-8 parts, 4-5.4 parts, 5-6.2 parts, 5.5-7.3 parts, 7.1-8 parts by weight. In some embodiments, the organic fiber is selected from polyethylene staple fibers or polypropylene staple fibers. The length of the organic fiber is 1-8 mm, and the linear density of the organic fiber is 1-2.5 Ttex. In the present application, the organic fiber can prevent solid-liquid separation and increase the viscosity of the product. At the same time, it can be quickly melted during high-temperature sintering, which helps to improve high-temperature fluidity. In a specific embodiment, the organic fiber is a polyethylene staple fiber with a length of 4 mm, a linear density of 1.56 Ttex, and the weight portions are 8 parts, 6.2 parts, and 4 parts.

[0063] In the repair material of the present invention, the weight of the expansion agent can be 0.05-1 part, 0.05-0.12 part, 0.11-0.61 part, 0.20-0.82 part, 0.46-1 part by weight. In some embodiments, the expansion agent is selected from one or both of kyanite and quartz, preferably kyanite, and the more preferred particle size specification of the kyanite is 35 mesh to 65 mesh, Al 2 O 3 Content ≥59wt%, Fe 2 O 3 Content ≤ 1.0wt%. The expansion agent in this application can partially eliminate the problem of cracks and peeling caused by shrinkage of the repair material during high temperature and cooling. Kyanite is usually a natural refractory raw material mineral with high refractoriness and large high-temperature volume expansion. It has parallel stripes on its crystal surface and its color is light blue or cyan, bright gray, etc. Kyanite has high refractoriness and irreversibly transforms into mullite and SiO at high temperature. 2 In a specific embodiment, the expansion agent is kyanite with a particle size of 35 mesh to 65 mesh, Al 2 O 3 Content ≥59wt%, Fe 2 O 3 The content is ≤1.0wt%; the weight portions are 0.7, 0.3 and 0.5.

[0064] In the repair material described in the present invention, the weight of the hardening accelerator can be 0.01-1 parts, 4-5.4 parts, 5-6.2 parts, 5.5-7.3 parts, 7.1-8 parts by weight. In some embodiments, the hardening accelerator is selected from one or more of aluminum hydroxide, talc, and magnesium oxide. The hardening accelerator in this application can shorten the coagulation and hardening time of the repair material. In a specific embodiment, the hardening accelerator is aluminum hydroxide; the weight parts are 0.5 parts, 0.3 parts and 0.5 parts.

[0065] In a specific embodiment, the repair material for the iron ditch of a gravity-flow blast furnace comprises the following raw materials in parts by weight:

[0066]

[0067] The second aspect of the present invention protects a method for preparing a repairing material for a self-flowing blast furnace tapping channel as described above, comprising the following steps:

[0068] Mixing the base material and the graphite powder in parts by weight to obtain a first premix;

[0069] The first premix, the organic fiber and the binder are mixed for a second time to obtain a second premix;

[0070] The second premix, the sintering agent, the expansion agent and the hardening agent are mixed for the third time to obtain the repairing material for the iron outlet channel of the self-flowing blast furnace.

[0071] In the preparation method of the present invention, the time of the first mixing is 5 to 15 minutes.

[0072] In the preparation method of the present invention, the second mixing time is 30 to 45 minutes.

[0073] In the preparation method of the present invention, the time of the third mixing is 5 to 10 minutes.

[0074] A third aspect of the present invention protects the use of the repairing material for a gravity-flow blast furnace tapping channel as described above in repairing a blast furnace tapping channel.

[0075] First, remove the residue on the surface of the blast furnace tapping channel that needs to be repaired, and then throw the repair material in the packaging bag directly to the part that needs to be repaired at high temperature. The repair material will enter the deep of the crack by itself to complete the repair, and it will be sintered after 15-30 minutes.

[0076] The specific effects are as follows: 1) The present invention uses alumina powder, magnesia and attapulgite as base materials. Alumina powder is mainly used to improve strength. Magnesia can play a skeleton role in the sintering process, which can improve the sintering process and improve the permeability of the material layer. At the same time, it can optimize the sintering quality of the repair material and improve the fluidity, thereby improving the bonding strength and compressive and flexural strength of the sintered layer, and improving the anti-scouring ability; the attapulgite powder stone rod crystal length is 1-5 microns, the diameter is between 20-70 nanometers, and it has a unique three-dimensional space chain structure and a special needle and rod-shaped crystal structure, so it has unusual colloid and adsorption properties, has certain thickening properties, stable chemical properties, and strong bonding force; the base material makes the repair material have higher strength and anti-scouring effect, which can ensure long-term use after repair. 2) The present invention adds silicon carbide powder and graphite powder. Silicon carbide powder as a sintering promoter can reduce the sintering time as much as possible and improve the high-temperature strength of the material; graphite powder can form a carbon skeleton after carbonization sintering, so that other components can form a high-strength repair body together. 3) The present invention uses thermoplastic, non-water-soluble phenolic resin and organic solution as binders, which not only avoids moisture in the repair material, but also the phenolic resin is thermoplastic, which can improve plasticity and enhance fluidity as the temperature rises. Phenolic resin decomposes at about 350-600°C as the temperature rises, so the sintering time is short and can be completed within 15-30 minutes. After the phenolic resin decomposes, its residual carbon content can reach 50-60%, forming a carbon chain network structure at high temperature, improving the sintering strength and anti-scouring and anti-erosion capabilities. 4) The present invention also adds organic fiber, expansion agent and hardening accelerator. The organic fiber mainly plays the role of preventing solid-liquid separation and improving the viscosity of the product. At the same time, it can be quickly melted during high-temperature sintering, which helps to improve high-temperature fluidity; the addition of expansion agent can prevent the material from shrinking during the sintering process and avoid the repair body from separating from the original matrix; the hardening accelerator can make the repair material quickly solidify after sintering, reduce the sintering molding time, and improve the strength of the repair body. 5) The preparation process of the present invention is simple and easy to use, suitable for large-scale promotion and application.

[0077] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0078] Before further describing the specific embodiments of the present invention, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments described below; it should also be understood that the terms used in the examples of the present invention are for describing the specific embodiments rather than for limiting the scope of protection of the present invention; in the present specification and claims, unless otherwise expressly stated herein, the singular forms "a", "an" and "the" include plural forms.

[0079] When the embodiments give numerical ranges, it should be understood that, unless otherwise specified in the present invention, both endpoints of each numerical range and any numerical value between the two endpoints can be selected. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meaning as those generally understood by those skilled in the art. In addition to the specific methods, equipment, and materials used in the embodiments, according to the grasp of the prior art by those skilled in the art and the record of the present invention, any methods, equipment, and materials of the prior art similar or equivalent to the methods, equipment, and materials described in the embodiments of the present invention can also be used to realize the present invention.

[0080] In the following embodiments of the present application, the particle size of the aluminum oxide powder is 0.2 to 1 mm, and the aluminum oxide powder contains Al 2 O 3 Content ≥98.5wt%, K 2 O and Na 2 The total content of O is ≤0.05wt%.

[0081] The particle size of the magnesia is 1 to 3 mm, the mass ratio of the magnesia with a particle size of 1 to 2.2 mm to the magnesia with a particle size of 2.2 to 3 mm is 70:30, and based on the total mass of the magnesia, the content of MgO in the magnesia is greater than 94.3 wt%, and the content of CaO, SiO 2 , Fe 2 O 3 The total content is ≤5.7wt%.

[0082] The rod crystal length of attapulgite is 1 to 5 μm and the diameter is 20 to 70 nm.

[0083] The particle size of the silicon carbide powder is 0.05-1 mm. Based on the total mass of the silicon carbide powder, the content of SiC in the silicon carbide powder is ≥98wt%.

[0084] The particle size of the graphite powder is 0.2-0.8 mm, and the graphite powder is selected from flake graphite and artificial electrode graphite, and the mass ratio of flake graphite to artificial electrode graphite is 1:1. The fluidity is higher at high temperature.

[0085] In the following embodiments of the present application, the phenolic resin was purchased from Wuxi Mingyang Adhesive Material Co., Ltd., with a viscosity of 120-250°, a solid content of 75±3, and free phenol %≤14%.

[0086] In the following examples of the present application, ethanol is used as the representative of the organic solvent.

[0087] In the following examples of the present application, the organic fiber was purchased from Liaoyang Huaying Fiber Co., Ltd., with a length of 4 mm and a linear density of 1.56 Ttex.

[0088] Examples 1-3

[0089] In the present embodiment 1-3, raw materials for repairing materials for self-flowing blast furnace tapping channels are provided, and the repairing materials for self-flowing blast furnace tapping channels are prepared and used to repair the tapping channels of blast furnaces. The materials include the following:

[0090] Raw material formula: refer to Table 1, weigh the base material, sintering agent, graphite powder, binder, organic fiber, expansion agent, and hardening agent.

[0091] The preparation method of the repair material for the blast furnace tapping channel is as follows:

[0092] The base material and graphite powder were added into a stirrer and stirred for 10 minutes to obtain a first premix.

[0093] The first premix, the organic fiber and the binder were continuously mixed in the mixer for 40 minutes until they were uniform, to obtain a second premix.

[0094] The second premix, the sintering agent, the expansion agent and the hardening agent are mixed in the agitator for 10 minutes until they are uniform, and the repair material for the blast furnace tapping channel is obtained, which is then packaged and stored in a greenhouse.

[0095] Applicable formula for repair materials for blast furnace iron outlet groove: first remove the surface residue of the blast furnace iron outlet groove to be repaired, and then directly throw the repair material with packaging bag (PE plastic bag) to the part to be repaired at high temperature. The repair material will enter the deep of the crack by itself to complete the repair, and it can be sintered after 15-30 minutes.

[0096] Table 1 (parts by weight)

[0097]

[0098] Comparative Examples 1-8

[0099] The formulations of Comparative Examples 1-8 refer to Table 1, and the preparation methods also refer to Example 1.

[0100] The self-flowing blast furnace tapping channel repair materials in Examples 1-3 and Comparative Examples 1-8 were tested respectively, and the test contents included room temperature flow value, compressive strength, flexural strength, hot flow value, etc. Among them,

[0101] Room temperature flow value: Tested according to the self-flow method in 5.4 of GB / T 4513.4-2017 "Monomorphous Refractory Materials Part 4: Determination of Castable Fluidity".

[0102] Compressive strength: The test is carried out according to the dense refractory material compressive strength liner test method in 7.2 of GB / T 5072-2008 "Test method for compressive strength of refractory materials at room temperature".

[0103] Flexural strength: Tested in accordance with GB / T 3001-2017 Test method for flexural strength of refractory materials at room temperature.

[0104] Hot flow value: The test method is to place the refractory brick (400mm*400mm*30mm) in a high-temperature electric furnace and burn it to 1000℃, take it out after keeping it warm for 1h, put a cylindrical mold with an inner diameter of 100mm on the brick, put in 0.5kg of mixed blast furnace tapping groove repair material, and quickly take out the mold. When the blast furnace tapping groove repair material loses fluidity, select 2-3 points to measure the diameter of the flow surface, and take the average value as the hot flow value of the test material. The test indicators and results are shown in Table 2.

[0105] Table 2

[0106]

[0107] It can be seen from Table 2 that the flow value of the blast furnace iron outlet groove repair material of the present application is more than 162mm at room temperature and more than 292mm at high temperature, and the compressive and flexural strengths are high after sintering. The use of the repair material to repair the blast furnace iron outlet groove can extend the iron-out days to more than 9 days, and the iron throughput reaches more than 2.25w, indicating that the repair body formed by the repair material has a strong bonding force with the original matrix; while Comparative Example 1 reduces the content of the base material relative to Example 3, Comparative Example 2 increases the content of the base material relative to Example 3, Comparative Example 3 reduces the graphite powder relative to Example 3, Comparative Example 4 reduces the organic fiber relative to Example 3, Comparative Example 5 reduces the thermoplastic and non-water-soluble phenolic resin relative to Example 3, Comparative Example 6 reduces magnesia relative to Example 3, Comparative Example 7 reduces attapulgite relative to Example 3, and Comparative Example 8 is a repair material formed according to CN1059414. From the above table, it can be seen that the increase or decrease of the above raw materials has different degrees of influence on the hot flow value, flow end time, compressive strength and flexural strength. It can be seen that Examples 1-3 are better solutions than Comparative Examples 1-5.

[0108] The above examples are for the purpose of illustrating the embodiments disclosed by the present invention and are not to be construed as limitations of the present invention. In addition, the various modifications listed herein and the variations of methods and compositions in the invention are obvious to those skilled in the art without departing from the scope and spirit of the present invention. Although the present invention has been specifically described in conjunction with various specific preferred embodiments of the present invention, it should be understood that the present invention should not be limited to these specific embodiments. In fact, various modifications obvious to those skilled in the art as described above to obtain the invention should be included within the scope of the present invention.

Claims

1. A repair material for the self-flowing blast furnace taphole, characterized in that, it comprises raw materials in the following parts by weight: Base material 40 - 60 parts Promoting sintering agent 5 - 8 parts Graphite powder 10 - 20 parts Binder 15 - 30 parts Organic fiber 4 - 8 parts Expansion agent 0.05 - 1 part Hardening accelerator 0.01 - 1 part; The base material is selected from alumina powder, magnesite and attapulgite, and the mass ratio of the alumina powder, magnesite and attapulgite is (12 - 18):(8 - 12):(20 - 30); the organic fiber is selected from polyethylene short fiber or polypropylene short fiber; the expansion agent is selected from one or both of kyanite and quartz; the hardening accelerator is selected from one or more of aluminum hydroxide, talc and magnesia.

2. The repair material according to claim 1, characterized in that, it includes at least one of the following technical features: A1) The particle size of the alumina powder is less than 2μm; A2) Based on the total mass of the alumina powder, the content of Al 2 O 3 in the alumina powder is ≥ 98.5 wt%, and the total content of K 2 O and Na 2 O is ≤ 0.05 wt%; A3) The particle size of the magnesite is 1 - 3mm; A4) Based on the total mass of magnesite, the content of MgO in the magnesite > 94.3 wt%, and the total content of CaO, SiO 2 and Fe 2 O 3 ≤ 5.7 wt%; A5) The rod crystal length of the attapulgite is 1 - 5μm, and the diameter is 20 - 70nm.

3. The repair material according to claim 1, characterized in that, the base material is a mixture of alumina powder, magnesite and attapulgite.

4. The repair material according to claim 1, characterized in that, the promoting sintering agent is selected from silicon carbide powder and / or, the particle size of the graphite powder is 20 - 75μm.

5. The repair material according to claim 4, characterized in that, it includes at least one of the following technical features: B1) The particle size of the silicon carbide powder is 325 mesh; B2) Based on the total mass of the silicon carbide powder, the content of SiC in the silicon carbide powder is ≥98wt%; B3) The graphite powder is selected from flake graphite and artificial electrode graphite.

6. The repair material according to claim 5, characterized in that, the mass ratio of the flake graphite and the artificial electrode graphite is (0.5 - 1):

1.

7. The repair material according to claim 1, characterized in that, the binder includes phenolic resin and organic solvent.

8. The repair material according to claim 7, characterized in that, the weight ratio of the phenolic resin and the organic solvent is (25 - 50):(50 - 75); and / or, the organic solvent is selected from one or more of ethanol, propanol, glycerol and ethylene glycol; and / or, the length of the organic fiber is 1 - 8mm, and the linear density of the organic fiber is 1 - 2.5Ttex.

9. The preparation method of the self-flowing blast furnace taphole repair material according to any one of claims 1 - 8, characterized in that, it includes the following steps: First mix the base material and the graphite powder according to the parts by weight to obtain a first premix; Second mix the first premix, the organic fiber and the binder to obtain a second premix; Third mix the second premix, the promoting sintering agent, the expansion agent and the hardening accelerator to obtain the blast furnace taphole repair material.

10. The preparation method according to claim 9, characterized in that, it includes at least one of the following technical features: D1) The time of the first mixing is 5 - 15min; D2) The time of the second mixing is 30 - 45min; D3) The time of the third mixing is 5 to 10 minutes.

11. Use of the repair material for blast furnace tapping troughs according to any one of claims 1-8 in blast furnace tapping troughs.

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