Energy-saving furnace lining ore heat self-baking carbon brick and preparation method thereof

Abstract

The invention belongs to the technical field of refractory materials, and particularly relates to an energy-saving furnace lining ore heat self-baking carbon brick and a preparation method thereof. The phosphorus-doped graphite, the electrically calcined anthracite, the silicon carbide and the silica powder are selected as main components, the asphalt, the lignite and the carbon fibers are used for forming a composite binder, meanwhile, the silica powder and the asphalt are subjected to modification treatment, the energy-saving furnace lining ore heat self-baking carbon brick is prepared, the heat conductivity coefficient and the compression strength of the carbon brick are effectively improved, and the service life of the furnace lining ore heat self-baking carbon brick is prolonged. And meanwhile, excellent erosion resistance is obtained.

Description

Technical Field

[0001] The invention belongs to the technical field of refractory materials, and particularly relates to an energy-saving furnace lining mineral heat self-baked carbon brick and a preparation method thereof. Background Art

[0002] A calcium carbide furnace is an industrial furnace used to produce calcium carbide (calcium carbide). This is usually achieved by heating coke (or metallurgical coke) and quicklime to approximately 2000°C in an electric arc furnace. Calcium carbide is one of the basic raw materials for the organic synthetic chemical industry and is mainly used to produce acetylene gas, which is then used to manufacture plastics, solvents, and other chemicals. As an important equipment for the production of calcium carbide, the calcium carbide furnace has high energy consumption, and the refractory materials in the high-temperature environment of the furnace are easily damaged. Carbon bricks are an important component of the calcium carbide furnace and are mainly used for lining to protect the furnace body and improve thermal efficiency. Carbon bricks have good high-temperature resistance and slag resistance. They can work stably in extremely high-temperature environments, reduce heat loss, and extend the service life of the furnace. Choosing suitable carbon bricks is crucial to the operating efficiency and economy of the calcium carbide furnace.

[0003] A Chinese patent (publication number CN118791313A) discloses a nanoporous blast furnace carbon brick comprising the following raw materials by weight: 1-2 parts of a graphene alcohol dispersion or aqueous graphene slurry, 55-67 parts of electrocalcined coal aggregate particles, 20-30 parts of graphite aggregate particles, 4-8 parts of silicon powder, 2-5 parts of alumina powder, and a resin. The preparation method comprises the following steps: S1, preparing a graphene alcohol dispersion or aqueous graphene slurry, and mixing the raw materials to form a paste; S2, pressing and curing the paste to form a brick; S3, loading the brick into a ring-type roasting furnace for high-temperature roasting, and deburring to obtain a finished nanoporous blast furnace carbon brick. However, existing carbon bricks used in calcium carbide furnaces suffer from insufficient thermal conductivity, insufficient compressive strength, and improved corrosion resistance, which seriously affect their practical use.

[0004] Therefore, how to screen suitable components and perform functional modification to prepare energy-saving furnace lining mineral thermal self-baked carbon bricks, effectively improve thermal conductivity and compressive strength, and obtain excellent corrosion resistance has become a direction that needs to be focused on. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to provide an energy-saving furnace lining mineral heat self-baked carbon brick and a preparation method thereof, aiming to solve the problems of insufficient thermal conductivity, insufficient compressive strength, and corrosion resistance when carbon bricks are used in calcium carbide furnaces in the existing technology.

[0006] The present invention selects phosphorus-doped graphite, electric-calcined anthracite, silicon carbide, and silicon micropowder as main components, and uses asphalt, lignin, and carbon fiber to form a composite binder. At the same time, the silicon micropowder and asphalt are modified to prepare energy-saving furnace lining mineral heat self-baked carbon bricks, which effectively improve the thermal conductivity and compressive strength of the carbon bricks and obtain excellent corrosion resistance.

[0007] The technical solutions adopted by the present invention to solve the above technical problems are as follows:

[0008] In a first aspect of the present invention, there is provided an energy-saving furnace lining mineral heat self-baked carbon brick comprising the following components in parts by weight:

[0009] 16-20 parts of phosphorus-doped graphite, 16-20 parts of electrocalcined anthracite, 18-22 parts of silicon carbide, 4-8 parts of silicon micropowder, 17-21 parts of asphalt, 4-8 parts of lignin and 3-5 parts of carbon fiber;

[0010] The preparation method of phosphorus-doped graphite includes: uniformly mixing 26 to 28 parts of phosphoric acid and 12 to 16 parts of acetic acid, and then adding 50 to 60 parts of graphite for pre-reaction to obtain a precursor; and transferring the precursor to a tubular furnace for calcination to obtain phosphorus-doped graphite.

[0011] As a preferred technical solution of the present invention, the pre-reaction conditions include: first ultrasonic shaking for 30 to 40 minutes, and then reacting at 170 to 180° C. for 12 to 16 hours.

[0012] As a preferred technical solution of the present invention, the calcination treatment conditions include: placing in a nitrogen atmosphere, heating from room temperature to 700-720°C at a heating rate of 5°C / min, keeping warm for 100-120 minutes, and cooling to room temperature.

[0013] Phosphorus-doped graphite regulates the pore structure of carbon materials by introducing phosphorus, reducing the number of micropores and increasing the pore size, thereby providing a more efficient heat conduction path. At the same time, phosphorus doping may produce new covalent bond networks in the carbon skeleton. These newly formed structures can serve as additional heat conduction channels, promote the rapid diffusion of heat, and effectively improve the thermal conductivity of carbon bricks.

[0014] As a preferred technical solution of the present invention, the silicon micropowder is modified silicon micropowder;

[0015] The preparation method of the modified silicon micropowder comprises: dispersing 2 to 4 parts of commercially available silicon micropowder in 240 to 260 parts of anhydrous ethanol, adding 4 to 6 parts of tetrabutyl titanate and uniformly dispersing the mixture by ultrasonication, adding 140 to 160 parts of deionized water and stirring the mixture to obtain a mass, grinding the mass into powder and then subjecting the powder to high-temperature treatment to obtain the modified silicon micropowder.

[0016] As a preferred technical solution of the present invention, the stirring treatment conditions include: stirring at a speed of 80-100 r / min for 4-6 hours, filtering, and drying at 80-90°C for 10-12 hours.

[0017] As a preferred technical solution of the present invention, the particle size of the commercially available silicon micropowder is 2 to 5 μm.

[0018] As a preferred technical solution of the present invention, the conditions for the high-temperature treatment include: heat treatment at 580-600° C. for 4-6 hours, and cooling to room temperature.

[0019] The titanium dioxide introduced by modified silicon powder has excellent acid and alkali resistance and oxidation resistance, and can effectively resist the erosion of slag and chemical substances. At the same time, titanium dioxide is evenly covered on the surface of silicon dioxide to form a dense protective layer and reduce pores, reducing the penetration of corrosive media, thereby improving the corrosion resistance of carbon bricks.

[0020] As a preferred technical solution of the present invention, the asphalt is an asphalt composite material.

[0021] The preparation method of the asphalt composite material comprises: adding 6 to 8 parts of carbon nanotubes to 90 to 100 parts of commercially available asphalt, performing a first high-speed shearing treatment, and then adding 8 to 10 parts of SBS rubber and performing a second high-speed shearing treatment to obtain the asphalt composite material.

[0022] As a preferred technical solution of the present invention, the conditions of the first high-speed shearing treatment include: a rotation speed of 2800-3000 r / min, a temperature of 160-170° C., and a time of 60-80 min.

[0023] As a preferred technical solution of the present invention, the conditions of the second high-speed shear treatment include: shearing at a speed of 4000-4200 r / min for 50-60 minutes at a temperature of 170-180°C, and then developing at 150-160°C for 30-40 minutes.

[0024] During the high-temperature sintering process of asphalt composite materials, the asphalt undergoes a carbonization reaction to generate a high-strength carbon-based skeleton structure, and SBS partially pyrolyzes at high temperature and combines with the asphalt carbonization products to further enhance the interfacial bonding force. Carbon nanotubes can be embedded in the carbonized asphalt matrix to form a three-dimensional reinforced network. The combined effect improves the compressive strength of the carbon brick.

[0025] The second aspect of the present invention provides a method for preparing the energy-saving furnace lining mineral heat self-baked carbon bricks as described in the first aspect, comprising the following steps:

[0026] Step S1: uniformly mixing 16 to 20 parts by weight of phosphorus-doped graphite, 16 to 20 parts of electrocalcined anthracite, 18 to 22 parts of silicon carbide, and 4 to 8 parts of silicon micropowder, and then adding 17 to 21 parts of asphalt, 4 to 8 parts of lignin, and 3 to 5 parts of carbon fiber, and ball milling to obtain a mixture;

[0027] Step S2: transferring the mixture into a forming mold and maintaining it at a pressure of 10 to 20 MPa for 4 to 6 minutes to obtain a carbon brick blank;

[0028] Step S3: keeping the carbon brick blank at 140-160° C. for 16-20 hours, and then calcining at 1100-1200° C. for 12-16 hours to obtain energy-saving furnace lining mineral heat self-baked carbon bricks.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] (1) During the high-temperature sintering process of the carbon bricks of the present invention, the diffusion rate of phosphorus atoms in phosphorus-doped graphite is accelerated, and some of them will migrate from the graphite to the surface of the modified silicon micropowder and form a titanium phosphate structure with titanium dioxide to enhance the interface bonding. At the same time, the carbon nanotubes have a highly conjugated hybrid carbon network, and the surface π electron cloud can be coupled with the electronic structure of the doped graphite, thereby improving the compressive strength and corrosion resistance through the synergistic effect of multiple components. At the same time, the carbon network formed at high temperature has good thermal conductivity, which can improve the thermal conductivity coefficient of the carbon bricks.

[0031] (2) The phosphorus-doped graphite of the present invention regulates the pore structure of the carbon material by introducing phosphorus, reduces the number of micropores, increases the pore size, and thus provides a more efficient heat conduction path. At the same time, phosphorus doping may produce a new covalent bond network in the carbon skeleton. These newly formed structures can serve as additional heat conduction channels, promote the rapid diffusion of heat, and effectively improve the thermal conductivity of carbon bricks.

[0032] (3) The titanium dioxide introduced into the modified silicon micropowder of the present invention has excellent acid and alkali resistance and oxidation resistance, and can effectively resist the erosion of slag and chemical substances. At the same time, the titanium dioxide is evenly covered on the surface of the silicon dioxide to form a dense protective layer and reduce the porosity, thereby reducing the penetration of the corrosive medium, thereby improving the corrosion resistance of the carbon brick.

[0033] (4) During the high-temperature sintering process of the asphalt composite material of the present invention, the asphalt undergoes a carbonization reaction to generate a high-strength carbon-based skeleton structure, and the SBS is partially pyrolyzed at high temperature and combined with the asphalt carbonization product to further enhance the interfacial bonding force. The carbon nanotubes can be embedded in the carbonized asphalt matrix to form a three-dimensional reinforced network. The combined effect improves the compressive strength of the carbon brick. DETAILED DESCRIPTION

[0034] For the convenience of understanding the present invention, the present invention is given below with examples. It should be understood by those skilled in the art that the examples are only for the purpose of helping to understand the present invention and should not be regarded as specific limitations of the present invention.

[0035] The sources of some components in the Examples and Comparative Examples are as follows:

[0036] Commercially available graphite, product number G434784, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0037] Electric calcined anthracite, Tianjin Dongli District Yueyang Industry and Trade Co., Ltd.

[0038] Silicon carbide, CAS No. 409-21-2, was purchased from Shanghai MacLean Biochemical Technology Co., Ltd.;

[0039] Commercially available silica powder I, product number S131652, with a particle size of 2.5 μm, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0040] Commercially available silica powder II, product number S305533, with a particle size of 35 μm, was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0041] Commercially available asphalt, product number WB93918, was purchased from Guangdong Wengjiang Chemical Reagent Co., Ltd.;

[0042] Lignin, guaiac lignin, CAS No. 9000-29-7, was purchased from Wuhan Fengzhulin Chemical Technology Co., Ltd. Carbon fiber, model SYT45, was purchased from Zhongfu Shenying Carbon Fiber Co., Ltd.;

[0043] Phosphoric acid, CAS No. 7664-38-2, was purchased from Sinopharm Chemical Reagent Co., Ltd.;

[0044] Acetic acid, CAS No. 141-78-6, was purchased from Sinopharm Chemical Reagent Co., Ltd.;

[0045] Tetrabutyl titanate, CAS No. 5593-70-4, was purchased from Shanghai MacLean Biochemical Technology Co., Ltd.;

[0046] Carbon nanotubes, product number C434649, were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.;

[0047] SBS rubber, brand SBSYH-796E, was purchased from Sinopec Baling Petrochemical Company.

[0048] Example 1

[0049] This embodiment provides a method for preparing energy-saving furnace lining mineral heat self-baked carbon bricks, comprising the following steps:

[0050] Step S1: 20 parts by weight of phosphorus-doped graphite, 20 parts of electrocalcined anthracite, 22 parts of silicon carbide, and 8 parts of modified silicon micropowder are mixed uniformly, and then 21 parts of asphalt composite material, 8 parts of guaiac, and 5 parts of carbon fiber are added and ball-milled to obtain a mixture;

[0051] Step S2: transferring the mixture into a forming mold and maintaining it under a pressure of 20 MPa for 4 minutes to obtain a carbon brick blank;

[0052] Step S3: keeping the carbon brick blank at 160° C. for 16 hours, and then calcining at 1200° C. for 12 hours to obtain energy-saving furnace lining mineral heat self-baked carbon bricks.

[0053] The phosphorus-doped graphite is prepared by uniformly mixing 28 parts of phosphoric acid and 16 parts of acetic acid, then adding 60 parts of graphite for a pre-reaction, first ultrasonically vibrating for 40 minutes, and then reacting at 180°C for 12 hours to obtain a precursor. The precursor is transferred to a tubular furnace for calcination treatment, placed in a nitrogen atmosphere, and heated from room temperature to 720°C at a rate of 5°C / min, kept warm for 100 minutes, and cooled to room temperature to obtain phosphorus-doped graphite.

[0054] Preparation of the modified silicon micropowder: In parts by weight, 4 parts of commercially available silicon micropowder I (article number S131652, particle size 2.5 μm) are dispersed in 260 parts of anhydrous ethanol, and then 6 parts of tetrabutyl titanate are added for ultrasonic dispersion, and then 160 parts of deionized water are added for stirring. The mixture is stirred at a speed of 100 r / min for 4 hours, filtered, and dried at 90° C. for 10 hours to obtain a block. The block is ground into powder and then subjected to high-temperature treatment, heat treatment at 600° C. for 4 hours, and cooling to room temperature to obtain modified silicon micropowder.

[0055] Preparation of the asphalt composite material: in parts by weight, 8 parts of carbon nanotubes are added to 100 parts of commercially available asphalt and subjected to a first high-speed shearing treatment (rotation speed of 3000 r / min, temperature of 170°C, time of 60 min), and then 10 parts of SBS rubber are added and subjected to a second high-speed shearing treatment, at a temperature of 180°C, at a rotation speed of 4200 r / min for 60 min, and then developed at 160°C for 30 min to obtain an asphalt composite material.

[0056] Example 2

[0057] This embodiment provides a method for preparing energy-saving furnace lining mineral heat self-baked carbon bricks, comprising the following steps:

[0058] Step S1: 16 parts by weight of phosphorus-doped graphite, 16 parts of electrocalcined anthracite, 18 parts of silicon carbide, and 4 parts of modified silicon micropowder are mixed uniformly, and then 17 parts of asphalt composite material, 4 parts of guaiac, and 3 parts of carbon fiber are added and ball-milled to obtain a mixture;

[0059] Step S2: transferring the mixture into a forming mold and maintaining it under a pressure of 10 MPa for 6 minutes to obtain a carbon brick blank;

[0060] Step S3: keeping the carbon brick blank at 140° C. for 20 hours, and then calcining at 1100° C. for 16 hours to obtain energy-saving furnace lining mineral heat self-baked carbon bricks.

[0061] The phosphorus-doped graphite is prepared by uniformly mixing 26 parts of phosphoric acid and 12 parts of acetic acid, then adding 50 parts of graphite for a pre-reaction, first ultrasonically vibrating for 30 minutes, and then reacting at 170°C for 16 hours to obtain a precursor. The precursor is transferred to a tubular furnace for calcination treatment, placed in a nitrogen atmosphere, and heated from room temperature to 700°C at a rate of 5°C / min, kept warm for 120 minutes, and cooled to room temperature to obtain phosphorus-doped graphite.

[0062] Preparation of the modified silicon micropowder: In parts by weight, 2 parts of commercially available silicon micropowder I (article number S131652, particle size 2.5 μm) are dispersed in 240 parts of anhydrous ethanol, and then 4 parts of tetrabutyl titanate are added for ultrasonic dispersion, and then 140 parts of deionized water are added for stirring, and the mixture is stirred at a speed of 80 r / min for 6 hours, filtered, and dried at 80° C. for 12 hours to obtain a block. The block is ground into powder and then subjected to high-temperature treatment, heat treatment at 580° C. for 6 hours, and cooled to room temperature to obtain modified silicon micropowder.

[0063] Preparation of the asphalt composite material: in parts by weight, 6 parts of carbon nanotubes are added to 90 parts of commercially available asphalt and subjected to a first high-speed shearing treatment (rotation speed of 2800 r / min, temperature of 160°C, time of 80 min), and then 8 parts of SBS rubber are added and subjected to a second high-speed shearing treatment, at a temperature of 170°C, at a rotation speed of 4000 r / min for 60 min, and then developed at 150°C for 40 min to obtain an asphalt composite material.

[0064] Example 3

[0065] This embodiment provides a method for preparing energy-saving furnace lining mineral heat self-baked carbon bricks, comprising the following steps:

[0066] Step S1: 18 parts by weight of phosphorus-doped graphite, 18 parts of electrocalcined anthracite, 20 parts of silicon carbide, and 6 parts of modified silicon micropowder are mixed uniformly, and then 19 parts of asphalt composite material, 6 parts of guaiac, and 4 parts of carbon fiber are added and ball-milled to obtain a mixture;

[0067] Step S2: transferring the mixture into a forming mold and maintaining it under a pressure of 15 MPa for 5 minutes to obtain a carbon brick blank;

[0068] Step S3: keeping the carbon brick blank at 150° C. for 18 hours, and then calcining at 1150° C. for 14 hours to obtain energy-saving furnace lining mineral heat self-baked carbon bricks.

[0069] The phosphorus-doped graphite is prepared by uniformly mixing 27 parts of phosphoric acid and 14 parts of acetic acid, then adding 55 parts of graphite for a pre-reaction, first ultrasonically vibrating for 35 minutes, and then reacting at 175°C for 14 hours to obtain a precursor. The precursor is transferred to a tubular furnace for calcination treatment, placed in a nitrogen atmosphere, and heated from room temperature to 710°C at a rate of 5°C / min, kept warm for 110 minutes, and cooled to room temperature to obtain phosphorus-doped graphite.

[0070] Preparation of the modified silicon micropowder: In parts by weight, 3 parts of commercially available silicon micropowder I (article number S131652, particle size 2.5 μm) are dispersed in 250 parts of anhydrous ethanol, and then 5 parts of tetrabutyl titanate are added for ultrasonic dispersion, followed by adding 150 parts of deionized water for stirring, stirring at a speed of 90 r / min for 5 hours, filtering, and drying at 85° C. for 11 hours to obtain a block, grinding the block into powder and then performing high-temperature treatment, heat treatment at 590° C. for 5 hours, and cooling to room temperature to obtain modified silicon micropowder.

[0071] Preparation of the asphalt composite material: in parts by weight, 7 parts of carbon nanotubes are added to 95 parts of commercially available asphalt and subjected to a first high-speed shearing treatment (rotation speed of 2900 r / min, temperature of 165°C, time of 70 min), and then 9 parts of SBS rubber are added and subjected to a second high-speed shearing treatment, at a temperature of 175°C, at a rotation speed of 4100 r / min for 55 min, and then developed at 155°C for 35 min to obtain an asphalt composite material.

[0072] Example 4

[0073] This embodiment provides a method for preparing a carbon brick, which differs from Example 1 in that commercially available silicon micropowder I (article number S131652, particle size 2.5 μm) is used instead of modified silicon micropowder.

[0074] Example 5

[0075] This embodiment provides a method for preparing a carbon brick, which differs from Example 1 in that commercially available silicon powder II (article number S305533, particle size 35 μm) is used instead of commercially available silicon powder I (article number S131652, particle size 2.5 μm) to prepare modified silicon powder.

[0076] Example 6

[0077] This embodiment provides a method for preparing a carbon brick, which differs from Example 1 in that commercially available asphalt (item number WB93918) is used instead of the asphalt composite material.

[0078] Comparative Example 1

[0079] This comparative example provides a method for preparing a carbon brick, which differs from Example 1 in that 20 parts of phosphorus-doped graphite are not added to the components.

[0080] Comparative Example 2

[0081] This comparative example provides a method for preparing a carbon brick, which differs from Example 1 in that 8 parts of modified silicon powder are not added to the components.

[0082] Comparative Example 3

[0083] This comparative example provides a method for preparing a carbon brick, which differs from Example 1 in that 21 parts of the asphalt composite material are not added to the components.

[0084] The performance of the carbon bricks provided in the above embodiments and comparative examples was tested, and the test methods were as follows: the thermal conductivity and compressive strength tests were tested with reference to the requirements of "YB / T 4666-2018 Silicon carbide carbon bricks for submerged arc furnaces", and the corrosion resistance test was tested with reference to the requirements of "GB / T 8931-2007 Test method for slag resistance of refractory materials".

[0085] The above performance test data is shown in Table 1.

[0086] Table 1 Performance test results

[0087]

[0088] From the above content, it can be seen that the present invention uses phosphorus-doped graphite, modified silicon micropowder and asphalt composite materials as main components to prepare energy-saving furnace lining mineral heat self-baked carbon bricks (Examples 1 to 3), whose thermal conductivity (600°C) is 29.38~29.53W / m·K, compressive strength is 59.04~59.21MPa, and erosion index (1600°C / 3h) is 2.15~2.22%.

[0089] Compared with Example 1, commercially available silicon powder I (article number S131652, particle size of 2.5 μm) is used instead of modified silicon powder, the thermal conductivity is reduced, the compressive strength is reduced, and the erosion resistance is deteriorated (Example 4); Compared with Example 1, commercially available silicon powder II (article number S305533, particle size of 35 μm) is used instead of commercially available silicon powder I (article number S131652, particle size of 2.5 μm) for the preparation of modified silicon powder. Since the particle size of commercially available silicon powder II is too large, the modification effect is not good, the thermal conductivity is reduced, the compressive strength is reduced, and the erosion resistance is deteriorated (Example 5); Compared with Example 1, commercially available silicon powder II (article number S305533, particle size of 35 μm) is used instead of commercially available silicon powder I (article number S131652, particle size of 2.5 μm) for the preparation of modified silicon powder. When asphalt (item number WB93918) is used to replace the asphalt composite material, the thermal conductivity is reduced, the compressive strength is reduced, and the erosion resistance is poor (Example 6); compared with Example 1, 20 parts of phosphorus-doped graphite are not added to the component, the thermal conductivity is reduced, the compressive strength is reduced, and the erosion resistance is poor (Comparative Example 1); compared with Example 1, 8 parts of modified silicon micropowder are not added to the component, the thermal conductivity is reduced, the compressive strength is reduced, and the erosion resistance is poor (Comparative Example 2); compared with Example 1, 21 parts of asphalt composite material are not added to the component, the thermal conductivity is reduced, the compressive strength is reduced, and the erosion resistance is poor (Comparative Example 3).

[0090] In summary, the present invention selects phosphorus-doped graphite, electric-calcined anthracite, silicon carbide, and silicon micropowder as main components, and uses asphalt, lignin and carbon fiber to form a composite binder. At the same time, the silicon micropowder and asphalt are modified to prepare energy-saving furnace lining mineral heat self-baked carbon bricks, which effectively improve the thermal conductivity and compressive strength of the carbon bricks and obtain excellent corrosion resistance.

Claims

1. An energy-saving furnace lining mineral heat self-baked carbon brick, characterized in that: In parts by weight, it comprises the following components: 16-20 parts of phosphorus-doped graphite, 16-20 parts of electrocalcined anthracite, 18-22 parts of silicon carbide, 4-8 parts of silicon micropowder, 17-21 parts of asphalt, 4-8 parts of lignin and 3-5 parts of carbon fiber; The preparation method of phosphorus-doped graphite includes: uniformly mixing 26 to 28 parts of phosphoric acid and 12 to 16 parts of acetic acid, and then adding 50 to 60 parts of graphite for pre-reaction to obtain a precursor; and transferring the precursor to a tubular furnace for calcination to obtain phosphorus-doped graphite.

2. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 1, characterized in that: The pre-reaction conditions include: first ultrasonic shaking for 30 to 40 minutes, and then reacting at 170 to 180° C. for 12 to 16 hours.

3. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 1, characterized in that: The calcination treatment conditions include: placing in a nitrogen atmosphere, heating from room temperature to 700-720° C. at a heating rate of 5° C. / min, keeping the temperature for 100-120 minutes, and cooling to room temperature.

4. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 1, characterized in that: The silicon micropowder is modified silicon micropowder; The preparation method of the modified silicon micropowder comprises: dispersing 2 to 4 parts of commercially available silicon micropowder in 240 to 260 parts of anhydrous ethanol, adding 4 to 6 parts of tetrabutyl titanate and uniformly dispersing the mixture by ultrasonication, adding 140 to 160 parts of deionized water and stirring the mixture to obtain a mass, grinding the mass into powder and then subjecting the powder to high-temperature treatment to obtain the modified silicon micropowder.

5. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 4, characterized in that: The stirring treatment conditions include: stirring at a speed of 80 to 100 r / min for 4 to 6 hours, filtering, and drying at 80 to 90° C. for 10 to 12 hours.

6. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 4, characterized in that: The particle size of the commercially available silicon micropowder is 2 to 5 μm.

7. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 1, characterized in that: The asphalt is an asphalt composite material, The preparation method of the asphalt composite material comprises: adding 6 to 8 parts of carbon nanotubes to 90 to 100 parts of commercially available asphalt, performing a first high-speed shearing treatment, and then adding 8 to 10 parts of SBS rubber and performing a second high-speed shearing treatment to obtain the asphalt composite material.

8. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 7, characterized in that: The conditions of the first high-speed shearing treatment include: a rotation speed of 2800 to 3000 r / min, a temperature of 160 to 170° C., and a time of 60 to 80 min.

9. The energy-saving furnace lining mineral heat self-baked carbon brick according to claim 7, characterized in that: The conditions of the second high-speed shearing treatment include: shearing at a speed of 4000-4200 r / min for 50-60 minutes at a temperature of 170-180° C., and then developing at a temperature of 150-160° C. for 30-40 minutes.

10. The method for preparing energy-saving furnace lining mineral heat self-baked carbon bricks according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step S1: uniformly mixing 16 to 20 parts by weight of phosphorus-doped graphite, 16 to 20 parts of electrocalcined anthracite, 18 to 22 parts of silicon carbide, and 4 to 8 parts of silicon micropowder, and then adding 17 to 21 parts of asphalt, 4 to 8 parts of lignin, and 3 to 5 parts of carbon fiber, and ball milling to obtain a mixture; Step S2: transferring the mixture into a forming mold and maintaining it at a pressure of 10 to 20 MPa for 4 to 6 minutes to obtain a carbon brick blank; Step S3: keeping the carbon brick blank at 140-160° C. for 16-20 hours, and then calcining at 1100-1200° C. for 12-16 hours to obtain energy-saving furnace lining mineral heat self-baked carbon bricks.

Images