Anhydrous foamed mud and its preparation method and use

Abstract

The application discloses anhydrous bubble mud and a preparation method and application thereof. The anhydrous bubble mud comprises the following raw materials in parts by weight: brown corundum 380-490 parts, coke powder 80 parts, silicon carbide 200-230 parts, silicon nitride 88-90 parts, clay 90-95 parts, synthetic resin 18 parts, tar 116-120 parts and additive 67-155 parts. The anhydrous bubble mud has the advantages of high high-temperature resistance, high impact resistance, small dry shrinkage, high stability, fast bonding time, high bonding degree of new and old bubble mud and long service time.

Description

Technical Field

[0001] This invention belongs to the field of ironmaking technology, specifically relating to anhydrous mud, its preparation method, and its uses. Background Technology

[0002] my country is a major iron-producing country with over a thousand blast furnaces, ranging in size from less than 100 cubic meters. 3 The largest exceeds 5000m 3 A blast furnace is equipped with both an iron tapping spout and a slag tapping spout. The iron tapping spout is used to release molten iron. The iron tapping spout is usually opened by drilling, which involves using an impact drill to drill a channel in the iron tapping spout so that the molten iron can be discharged out of the furnace through the channel.

[0003] Taphole clay is a mud-like solid refractory material used to seal the taphole during the blast furnace ironmaking process. It is generally divided into two main categories: water-based taphole clay and waterless taphole clay. Water-based taphole clay is generally used in small and medium-sized blast furnaces, while waterless taphole clay is used in large blast furnaces. Compared with the former, waterless taphole clay has advantages such as high strength, erosion resistance, and high temperature erosion resistance.

[0004] Water-based taphole clay is made primarily from coke powder, clay powder, bauxite clinker, and coal tar pitch, mixed with water and milled in a mixer for a certain period of time to become the taphole clay used in blast furnaces. Water-based taphole clay has a low bulk density and poor resistance to slag and iron corrosion. When used to plug the blast furnace taphole, it easily leads to insufficient taphole length, resulting in coke leakage, incomplete venting during tapping, and incomplete removal of molten slag and iron, thus affecting normal blast furnace production. Resistance to slag-iron erosion includes resistance to mechanical and chemical erosion. Mechanical erosion occurs when the taphole is drilled open during tapping, allowing hot molten iron and slag to flow out, subjecting the taphole clay to temperatures exceeding 1500°C. When the slag is removed and the taphole is re-sealed with taphole clay, the temperature drops rapidly from 1500°C to around 200°C upon contact with the new clay. This repeated action generates significant thermal stress within the old clay, easily leading to arc-shaped cracks centered on the taphole. Chemical erosion occurs when the blast furnace feed contains a large amount of sintered ore and a small amount of pelletized ore and other minerals, resulting in a high slag-to-iron ratio. Prolonged contact between the taphole clay and the molten iron and slag causes a chemical reaction, eroding the clay. This reaction readily produces fir olivine (F₂S), fir cordierite (F₂AS₅), tetracalcium aluminoferrite (C₄AF), and manganese cordierite (2MnO₂Al₂O₃). 35 Low-melting-point mineral phases such as SiO2 tend to form liquid phases during tapping. These phases are washed away by the molten iron slag, causing the tapping hole to enlarge and resulting in molten iron rushing out of the tapping hole rapidly, which affects the stability of the tapping hole.

[0005] The standard YB / T 4196-2009, "Anhydrous Blast Furnace Mud," stipulates that anhydrous taphole mud for blast furnaces is composed of refractory aggregates, fine powder, binders, and liquids, with a moisture content of no more than 2%. After burning, it forms carbon bonds and is used as a refractory material to block the blast furnace taphole.

[0006] In recent years, the automation level of blast furnace ironmaking in China has generally improved, developing towards larger scale (over 5000 cubic meters), intelligentization, and cleaner production. The number of tapping operations at the blast furnace taphole has decreased, while the tapping time has increased, placing increasingly higher demands on the performance of the taphole clay. Compared to 10 years ago, the average tapping time per operation has increased by 15-20%, with some steel plants reaching 150 minutes. This places higher demands on the clay's resistance to erosion, the bonding between new and old clay materials, as well as its filling properties, sintering properties, and stability.

[0007] Poor quality taphole clay can lead to problems such as difficulty in opening the taphole, shallow taphole, and poor resistance to high-temperature erosion, and may even cause a major blowout. High-quality taphole clay ensures stable tapping, resists slag and iron erosion, is easy to apply, protects the hearth, and has low consumption per unit of taphole clay.

[0008] Therefore, a high-quality anhydrous gun clay and its preparation method were developed to improve the production efficiency of blast furnaces, enhance environmental protection, and ensure production safety. Summary of the Invention

[0009] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide anhydrous sludge, its preparation method and uses, to solve the problems in the prior art.

[0010] To achieve the above and other related objectives, the present invention is obtained through the following technical solution.

[0011] One objective of this invention is to provide a waterless foaming mud, which comprises the following raw materials in parts by weight:

[0012]

[0013] In some embodiments, the brown fused alumina includes coarse-grained brown fused alumina, medium-grained brown fused alumina, fine-grained brown fused alumina, and fine powder brown fused alumina. The coarse-grained brown fused alumina has a particle size of 1 to 3 mm, the medium-grained brown fused alumina has a particle size of 0.21 to 1 mm, the fine-grained brown fused alumina has a particle size of less than 0.21 to 0.07 mm, and the fine powder brown fused alumina has a particle size of less than 0.07 mm.

[0014] In some specific embodiments, the mass percentage of the fine brown corundum powder is no more than 5 wt%, based on the total mass of the anhydrous sludge.

[0015] In some specific embodiments, the mass percentage of the coarse-grained brown corundum is 18-25 wt%, based on the total mass of the anhydrous sludge.

[0016] In some specific embodiments, the mass ratio of coarse-grained brown fused alumina, medium-grained brown fused alumina, fine-grained brown fused alumina and fine powder brown fused alumina is (18-25):(6-13):(2-7):(2-7).

[0017] In some embodiments, the silicon carbide includes medium-sized silicon carbide and fine silicon carbide, wherein the medium-sized silicon carbide has a particle size of 0.07 to 0.21 mm, and the fine silicon carbide has a particle size of less than 0.07 mm.

[0018] In some specific embodiments, the mass ratio of medium-sized silicon carbide to fine-powdered silicon carbide is (6-15):(6-15).

[0019] In some embodiments, the particle size of the coke powder is 0.1 to 1 mm.

[0020] In some embodiments, the silicon nitride has a particle size of 0.80 to 0.83 mm.

[0021] In some embodiments, the clay has a particle size of 0.05–0.07 mm. In this application, clay is used as both a dispersant and a binder. The amount of clay added is 6–12%. Too low a concentration will result in poor dispersibility and adhesion, while too high a concentration will lead to loose, unconsolidated clay.

[0022] In some embodiments, the particle size of the synthetic resin is 0.001 to 0.090 mm.

[0023] In some embodiments, the synthetic resin is selected from phenolic resin powder.

[0024] In some specific embodiments, the number-average molecular weight of the synthetic resin is 300 to 700.

[0025] In some embodiments, the tar is sourced from Shanghai Baosteel Chemical Co., Ltd. The tar in this application has better fluidity and is produced by a chemical plant, while traditional coal tar has high viscosity and a long binding time.

[0026] In some embodiments, the particle size of the additive is 0.001 to 0.090 mm.

[0027] In some specific embodiments, the additive is selected from one or more of sericite, titanium dioxide, silicon metal powder, and boron carbide. The additive has better refractoriness than brown fused alumina.

[0028] In some specific embodiments, the sericite has a refractoriness of 1320–1480°C, a SiO2 content of 71–77%, a water content of <2%, an Al2O3 content of 14–18%, an Fe2O3 content of <1.1%, and a K2O content of <4%.

[0029] The second objective of this invention is to provide a method for preparing anhydrous sludge as described above, comprising the following steps:

[0030] Brown fused alumina, coke powder, silicon nitride, clay and additives are mixed in parts by weight, then silicon carbide and synthetic resin are added and the mixture is rolled. Tar is added during rolling, and the mixture is extruded, molded and cured to obtain the anhydrous blister mud.

[0031] In some embodiments, the rolling time is 40 to 70 minutes.

[0032] In some implementations, the curing period is 5 to 7 days.

[0033] In some embodiments, a portion of the total tar is added for the first rolling, followed by the addition of the remaining tar for a second rolling. Preferably, the first rolling time is 30–45 minutes. More preferably, the second rolling time is 10–40 minutes.

[0034] In some specific implementations, one portion of the tar accounts for 95-98 wt% of the total tar.

[0035] The third objective of this invention is to provide the use of anhydrous mud as described above in blast furnace ironmaking.

[0036] This application discovers that tar and resin can replace bitumen, making it more environmentally friendly. The anhydrous blasting mud of this application, through the synergistic combination of various raw materials, exhibits excellent refractory material properties: silicon carbide is resistant to slag and iron erosion, has high temperature resistance, and good wear resistance; corundum also exhibits good slag and iron erosion resistance, wear resistance, and chemical stability. Additives can improve the high-temperature bonding of the blasting mud. Furthermore, the coke powder in the anhydrous blasting mud will burn in the blast furnace to form CO, and silicon nitride will react with CO to precipitate silicon. Silica can enhance the oxidation resistance of the blasting mud.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1) The anhydrous taphole clay of this application is more economical and environmentally friendly, possessing excellent oxidation resistance, high-temperature resistance, and slag-iron erosion resistance. Generally, the tapping pressure at the taphole of a large blast furnace is around 23-30 MPa; pressures exceeding 30 MPa are considered high and unfavorable for tapping the clay. Since furnace conditions are dynamically changing, the taphole clay product can be adapted to different blast furnace operating conditions based on the user's varying tapping pressure requirements.

[0039] 2) The anhydrous taphole clay of this application has a low drying shrinkage rate, high bonding strength between new and old taphole clay, and is resistant to slag and iron erosion, making it suitable for use in large blast furnace tapholes of 5000 cubic meters and above.

[0040] 3) The unit consumption of anhydrous taphole mud in this application has been reduced from 0.8 kg / t to 0.35 kg / t. Unit consumption refers to the number of kilograms of wastewater and taphole mud consumed per ton of molten iron. Taphole mud can maintain the stability of taphole diameter, which is conducive to the clean discharge of molten slag and iron, and can meet the production needs of large blast furnace ironmaking, save energy and protect the environment. Attached Figure Description

[0041] Figure 1 The process flow diagram of the method for preparing the waterless foamed mud of the present invention is shown.

[0042] Figure 1 The attached figures are labeled as follows:

[0043] 1 silo

[0044] 2 horizontal conveyor belts

[0045] 3. Feeding belt

[0046] 4. Fabric feeder

[0047] 5-bucket elevator

[0048] 6 mud rollers

[0049] 7. Disc-type fabric feeder

[0050] 8 molding machine

[0051] 9 Packaging Machines

[0052] 10 Placement Boxes

[0053] 11 Tar Storage Tanks

[0054] 12 Tar delivery pipes. Detailed Implementation

[0055] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0056] Before further describing 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 terminology used in the embodiments of the present invention is for describing specific embodiments and not for limiting the scope of protection of the present invention. Test methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the respective manufacturers.

[0057] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in the present invention, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art. In addition to the specific methods, apparatus, and materials used in the embodiments, based on the knowledge of the prior art possessed by one of ordinary skill in the art and the description of this invention, any prior art methods, apparatus, and materials similar to or equivalent to those described, apparatus, and materials in the embodiments of this invention may be used to implement the present invention.

[0058] The first aspect of this application provides a waterless foaming mud, which comprises the following raw materials in parts by weight:

[0059]

[0060] Preferably, the brown fused alumina can be 380-395 parts by weight, 390-400 parts by weight, or 395-490 parts by weight. In some preferred embodiments, it is 465 parts, 480 parts, or 485 parts by weight.

[0061] Preferably, the silicon carbide can be 200-213 parts by weight, 211-226 parts by weight, or 218-230 parts by weight. In some preferred embodiments, it is 200 parts, 210 parts, or 230 parts by weight.

[0062] Preferably, the silicon nitride can be 88 parts, 89 parts, or 90 parts.

[0063] Preferably, the clay can be 90-92.6 parts by weight, 91.2-94.1 parts by weight, or 93.1-95 parts by weight. In some preferred embodiments, it is 90 parts, 94 parts, and 95 parts by weight.

[0064] Preferably, the tar can be 116-118 parts by weight, 117-119 parts by weight, or 118-120 parts by weight. In some preferred embodiments, it is 116 parts, 118 parts, or 120 parts by weight.

[0065] Preferably, the additive can be 67-82 parts by weight, 79-100 parts by weight, or 85-155 parts by weight. In some preferred embodiments, it is 67 parts, 100 parts, or 155 parts.

[0066] Preferably, the brown fused alumina includes coarse-grained brown fused alumina, medium-grained brown fused alumina, fine-grained brown fused alumina, and fine powder brown fused alumina. The coarse-grained brown fused alumina has a particle size of 1-3 mm, the medium-grained brown fused alumina has a particle size of 0.21-1 mm, the fine-grained brown fused alumina has a particle size of 0.21 mm-0.07 mm, and the fine powder brown fused alumina has a particle size of less than 0.07 mm.

[0067] More preferably, based on the total mass of the anhydrous sludge, the mass percentage of the coarse-grained brown fused alumina is 18-25 wt%. In this application, the amount of coarse-grained brown fused alumina should not be too much or too little; too much will lead to reduced bonding strength and viscosity, while too little will lead to reduced strength. Preferably, the mass percentage of coarse-grained brown fused alumina can be 18-22 wt%, 20-24 wt%, or 22-25 wt%, for example, 18.5%, 19.8%, or 20%.

[0068] More preferably, based on the total mass of the anhydrous sludge, the mass percentage of the fine-powdered brown fused alumina is not higher than 5 wt%. In this application, the amount of fine-powdered brown fused alumina should not be too much or too little; too much will lead to reduced strength, while too little will lead to reduced bonding strength and viscosity. Preferably, the mass percentage of coarse-grained brown fused alumina can be 0.001–1 wt%, 0.5–3 wt%, or 2–5 wt%, for example, 3.1% or 3.2%.

[0069] More preferably, the mass ratio of coarse-grained brown fused alumina, medium-grained brown fused alumina, fine-grained brown fused alumina, and fine powdery brown fused alumina is (6-13):(18-25):(2-7):(2-7). Even more preferably, the mass ratio can be (6-13):(18-21):(2-7):(2-7), (6-13):(19-23):(2-7):(2-7), or (6-13):(20-25):(2-7):(2-7). In some preferred embodiments, the ratios are 8:21:10:4:3.5, 8:22:10:4.5:3.5, and 8:22:10.5:4.5:3.5.

[0070] Preferably, the silicon carbide includes medium-sized silicon carbide and fine silicon carbide, wherein the particle size of the medium-sized silicon carbide is 0.21 to 1 mm, and the particle size of the fine silicon carbide is less than 0.07 mm.

[0071] More preferably, the mass ratio of medium-sized silicon carbide to fine silicon carbide is (6-15):(6-15). Even more preferably, the mass ratio can be (6-9):(6-15), (8-12):(6-15), or (11-15):(6-15). In some preferred embodiments, it is 1:1.

[0072] Preferably, the additive is selected from one or more of sericite, titanium dioxide, silicon metal powder, and boron carbide. In one specific embodiment, the additive is sericite, titanium dioxide, and boron carbide; in another specific embodiment, the additive is titanium dioxide and boron carbide; and in yet another specific embodiment, the additive is sericite and silicon metal powder.

[0073] Preferably, the synthetic resin is selected from phenolic resin powder. More preferably, the number average molecular weight of the synthetic resin is 300-700. The phenolic resin was purchased from Wuxi Baoyi Refractory Materials Co., Ltd.

[0074] Preferably, the particle size of the coke powder is 0.1 to 1 mm.

[0075] Preferably, the silicon nitride has a particle size of 0.80 to 0.83 mm.

[0076] Preferably, the clay has a particle size of 0.05 to 0.07 mm.

[0077] Preferably, the particle size of the synthetic resin is 0.001 to 0.090 mm.

[0078] Preferably, the particle size of the admixture is 0.001 to 0.090 mm.

[0079] A second aspect of the present invention provides a method for preparing anhydrous sludge as described above, comprising the following steps:

[0080] Brown fused alumina, coke powder, silicon nitride, clay and additives are mixed in parts by weight, and then silicon carbide and synthetic resin are added for compaction. Tar is added during compaction, and the mixture is extruded, molded and cured to obtain the anhydrous foam-free mud.

[0081] Preferably, the rolling time is 40 to 70 minutes.

[0082] Preferably, a portion of the total tar is added for the first compaction, followed by the addition of the remaining tar for a second compaction. More preferably, the portion of tar accounts for 95-98% of the total tar. More preferably, the first compaction lasts 30-45 minutes. More preferably, the second compaction lasts 10-40 minutes. In a preferred embodiment, 98% of the total tar is added for the first compaction, lasting 30-45 minutes, followed by the addition of the remaining tar for a second compaction lasting 10 minutes. This results in a more uniform and better-bonded anhydrous clay. Real-time monitoring of the Marshall value is performed after the first compaction, and the second compaction continues without interruption, which helps ensure the anhydrous clay meets the requirements. The Marshall value can be measured using a specialized instrument, such as a Marshall value tester.

[0083] Preferably, the curing time is 5-7 days. The curing method includes autoclaving or open-air natural curing. Preferably, the temperature for open-air natural curing is 20-40℃, more preferably 20-30℃, more preferably 25-35℃, and more preferably 30-40℃; the humidity for open-air natural curing is 60%-75%, more preferably 60%-68%, more preferably 65%-72%, and more preferably 70%-75%; the time for open-air natural curing is 2-6 hours, more preferably 2-4 hours, more preferably 3-5 hours, and more preferably 4-6 hours. Preferably, the pressure for autoclaving is 1.0-2.0 MPa, more preferably 1.0-1.5 MPa, more preferably 1.4-1.8 MPa, and more preferably 1.6-2.0 MPa; the time for autoclaving is 6-10 hours, more preferably 6-8 hours, more preferably 7-9 hours, and more preferably 8-10 hours.

[0084] A third aspect of the invention provides the use of anhydrous sludge as described above in blast furnace ironmaking.

[0085] like Figure 1 The diagram shown is a process flow chart of the preparation method of the present invention. 1 is a silo, 2 is a horizontal conveyor belt, 3 is a feeding belt, 4 is a material distributor, 5 is a bucket elevator, 6 is a sludge mill, 7 is a disc material distributor, 8 is a molding machine, 9 is a packaging machine, 10 is a placement box, 11 is a tar storage tank, and 12 is a tar conveying pipe.

[0086] Brown corundum, coke powder, silicon nitride, clay, and additives are mixed in silo 1 according to their weight proportions. The mixed material is then fed into sludge mill 6 via horizontal conveyor belt 2, feeding belt 3, distributor 4, and bucket elevator 5. Silicon carbide and synthetic resin are then added for crushing. Tar is placed in tar storage tank 11 and fed into sludge mill 6 via tar conveyor pipe 12. After crushing, it is fed into molding machine 8 via disc distributor 7 and extruded. The formed anhydrous sludge is packaged by packaging machine 9 and placed in placement box 10.

[0087] The method for preparing waterless foamed mud in this application is shorter than that of traditional processes. The incoming material is finished powder or raw material that meets the particle size requirements. It eliminates the processing, crushing and grinding steps. The equipment has stable performance and can realize continuous production. The quality of the produced foamed mud product is stable.

[0088] Table 1. Raw material sources and parameters

[0089]

[0090]

[0091] Examples 1-5

[0092] Referring to the formula in Table 2, the raw materials were mixed, rolled, and cured to obtain water-free mud. The flexural strength, compressive strength, shrinkage rate, and setting time were tested, and the results are shown in Table 3.

[0093] Table 2 (parts by weight)

[0094]

[0095]

[0096] As shown in Table 2, the addition of titanium dioxide, boron carbide, and synthetic resin in Example 1 improved the quality of the gunning clay. Combinations of brown corundum with different particle sizes and proportions further improved the high-temperature resistance, wear resistance, and oxidation resistance of the gunning clay. Compared with Examples 2 and 3, the gunning clay produced in Example 2 was slightly softer due to its slightly higher tar content. The gunning clay produced in Example 2 had moderate hardness. The addition of titanium dioxide resulted in good dispersibility and excellent erosion resistance at high temperatures, and the gunning clay was less prone to cracking during the high-temperature drying process. The gunning clay produced in Example 3 was slightly harder. The addition of silicon powder made the gunning clay material more compact, with good high-temperature resistance, strong slag resistance, and high thermal stability.

[0097] Comparative Example 1

[0098] The difference between Comparative Example 1 and Example 3 is that no metallic silicon powder was added, and the amount of tar added was higher than that in Example 1. Everything else is the same as in Example 3. The formulation is shown in Table 2.

[0099] Comparative Example 2

[0100] The difference between Comparative Example 1 and Example 3 is that the amount of coke powder added is lower in Comparative Example 3, specifically 30 parts; all other aspects are the same as in Example 3. The formula is shown in Table 2.

[0101] Comparative Example 3

[0102] The difference between Comparative Example 1 and Example 3 is that the coarse-grained brown fused alumina is less than that in Comparative Example 3, while the medium-grained brown fused alumina is more than that in Comparative Example 3, specifically 110 parts and 205 parts respectively. All other aspects are the same as in Example 3. The formulation is shown in Table 2.

[0103] The anhydrous blister mud obtained in Examples 1-3 and Comparative Examples 1-3 was tested for properties such as flexural strength, room temperature compressive strength, drying shrinkage rate, and setting time. The anhydrous blister mud was then used in a blast furnace, and the results were observed and recorded for one week. The results are shown in Table 3.

[0104] Flexural strength: The test method refers to the room temperature compressive strength test in "YB / T 4196-2009 Anhydrous Soaked Mud for Blast Furnace", specifically the test of the sample after carbonization at 1400℃ for 2h in accordance with GB / T5072.

[0105] Room temperature compressive strength: The test method refers to the room temperature compressive strength test in "YB / T 4196-2009 Anhydrous Soaked Mud for Blast Furnace", specifically the test of the sample after carbonization at 1350℃ for 3h in accordance with GB / T5072.

[0106] Shrinkage rate: ±1% required.

[0107] Setting time: less than or equal to 30 minutes.

[0108] Table 3 Performance Tests

[0109]

[0110]

[0111] As shown in Table 3, the flexural strength and compressive strength of the taphole clay of this application are higher than those of comparative examples 1-3, indicating that the anhydrous taphole clay obtained in this application has strong high-temperature resistance and impact resistance. In addition, the anhydrous taphole clay of this application has a small drying shrinkage rate, and the taphole clay is easy to undergo small thermal expansion and contraction deformation. The smaller the high-temperature shrinkage rate, the better, which ensures safe use in blast furnaces and easy opening. Furthermore, the anhydrous taphole clay of this application has a fast setting time, indicating that the bonding degree between the new and old taphole clay is high after drilling with a room temperature drilling machine.

[0112] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A waterless, foam-free mud, characterized in that, The anhydrous sludge comprises the following raw materials in parts by weight: Brown fused alumina 380-490 parts 80 portions of caramel powder 200-230 parts of silicon carbide 88-90 parts of silicon nitride 90-95 parts clay 18 parts of synthetic resin 116-120 parts tar 67-155 parts of admixture; Brown fused alumina includes coarse-grained, medium-grained, fine-grained, and fine-powdered brown fused alumina. The coarse-grained brown fused alumina has a particle size of 1–3 mm, the medium-grained brown fused alumina has a particle size of 0.21–1 mm, the fine-grained brown fused alumina has a particle size of 0.21 mm–0.07 mm, and the fine-powdered brown fused alumina has a particle size less than 0.07 mm. The mass of the coarse-grained, medium-grained, fine-grained, and fine-powdered brown fused alumina... The ratio is (18-25):(6-13):(2-7):(2-7); the additive is selected from one or more of sericite, titanium dioxide, silicon metal powder, and boron carbide; the synthetic resin is selected from phenolic resin powder; the number average molecular weight of the synthetic resin is 300-700, and the particle size of the synthetic resin is 0.001-0.090 mm; the particle size of the coke powder is 0.1-1 mm; and the particle size of the silicon nitride is 0.80-0.83 mm.

2. The waterless sludge as described in claim 1, characterized in that, The silicon carbide includes medium-sized silicon carbide and fine silicon carbide, wherein the particle size of the medium-sized silicon carbide is 0.21 to 1 mm, and the particle size of the fine silicon carbide is less than 0.07 mm.

3. The waterless sludge as described in claim 2, characterized in that, The mass ratio of medium-sized silicon carbide to fine-powdered silicon carbide is (6-15):(6-15).

4. The waterless sludge as described in claim 1, characterized in that, The clay has a particle size of 0.05–0.07 mm; And / or, the particle size of the admixture is 0.001 to 0.090 mm.

5. The method for preparing anhydrous sludge according to any one of claims 1 to 4, characterized in that, Includes the following steps: Brown fused alumina, coke powder, silicon nitride, clay and additives are mixed in parts by weight, then silicon carbide and synthetic resin are added and the mixture is rolled. Tar is added during rolling, and the mixture is extruded, molded and cured to obtain the anhydrous blister mud.

6. The preparation method according to claim 5, characterized in that, First, add a portion of the total tar volume for the first rolling, and then add the remaining tar for the second rolling. And / or, the rolling time is 40 to 70 minutes.

7. The preparation method according to claim 6, characterized in that, A portion of the tar accounts for 95-98 wt% of the total tar content; And / or, the first compaction time is 30 to 45 minutes; And / or, the second compaction time is 10 to 40 minutes.

8. The preparation method according to claim 5, characterized in that, The maintenance period is 5 to 7 days.

9. The use of the anhydrous mud as described in any one of claims 1 to 4 in blast furnace ironmaking.

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