Preparation method of environment-friendly anhydrous stemming

Abstract

The invention relates to a preparation method of environment-friendly anhydrous stemming. The preparation method comprises the following steps: step 1, preparing materials; step 2, drying; step 3, grinding; step 4, crushing; (5) mixing: adding the mixed material crushed in the step (4) into an anhydrous stemming stirrer, and stirring for 10-15 minutes to fully mix the materials; 6, an expanding agent and 2% of a binding agent are added into the anhydrous stemming stirrer to be mixed with the mixture treated in the step 5, and stirring continues to be conducted for 15-30 min; 7, the prepared pug is ground in a pug grinding machine with the diameter phi of 1200 * 500 mm; step 8; after dry grinding and mixing are conducted for 3-4 minutes, the remaining 98% of the binding agent is added, grinding is conducted again for 35 minutes within the temperature range of 10-30 DEG C, then materials are sampled, and the Marshall value of the materials is detected; and 9, packaging the qualified stemming with a plastic bag by a forming machine, boxing, and feeding to a blast furnace for use. The invention has the advantages of energy conservation, environmental protection, convenience, durability, strong erosion resistance and good plasticity.

Description

Technical Field

[0001] The invention belongs to the technical field of anhydrous taphole mud, and particularly relates to a method for preparing environmentally friendly anhydrous taphole mud. Background Art

[0002] Cannon clay is a refractory material used to plug the iron mouth of an iron-making blast furnace. The quality of its performance is directly related to whether the blast furnace can operate safely. With the large-scale blast furnace, high wind pressure, and the discharge of a large amount of slag iron, the quality requirements for the cannon clay for plugging the iron mouth are getting higher and higher. With the development and progress of society, mankind has long recognized the great harm of traditional coal tar and asphalt combined with blast furnace cannon clay. Although they have excellent plasticity and durability, coal tar and asphalt have complex components and are rich in 16 polycyclic aromatic hydrocarbons with strong carcinogenic effects that are recognized worldwide, the most typical of which is benzo(a)pyrene, with a content of more than 8400ppm; compared with coal tar and asphalt, phenolic resin combined with cannon clay has a fast curing speed and less smoke, but the phenol and formaldehyde monomers contained in it have also been listed as hazardous substances, and practice has proved that it has technical and usage defects; therefore, it is very necessary to provide an environmentally friendly anhydrous cannon clay preparation method that is energy-saving, environmentally friendly, convenient, durable, has strong corrosion resistance, and has good plasticity. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a method for preparing an environmentally friendly anhydrous taphole mud which is energy-saving, environmentally friendly, convenient, durable, has strong corrosion resistance and good plasticity.

[0004] The object of the present invention is achieved in this way: the method for preparing an environmentally friendly anhydrous taphole mud comprises the following steps: Step 1: Prepare materials: weigh the granular aggregate, aggregate filler, fine powder, additives and binder according to the proportions. The weighing error shall not exceed 1%. Step 2: Drying: Heat the granular aggregate, aggregate filler, fine powder, additive, and binder, stir, and dehydrate them. When the water content is less than 0.5wt%, stop heating and store them at a constant temperature for later use. Step 3: Grinding: Put the granular aggregate, aggregate filler, fine powder and additives into the ball mill for grinding; Step 4: Crushing: Put the material ground in step 3 into an airflow superfine pulverizer for crushing; Step 5: Mixing: Add the crushed mixture in step 4 into the waterless taphole mud mixer and stir for 10 to 15 minutes to fully mix the materials; Step 6: Add the expansion agent and 2% of the binder into the anhydrous taphole mud mixer and mix with the mixed material after the treatment in step 5, and continue stirring for 15 to 30 minutes; Step 7: The prepared mud is ground in a Φ1200×500mm mud mill; Step 8: After dry milling and mixing for 3-4 minutes, add the remaining 98% of the binder, and mill for another 35 minutes at a temperature range of 10-30°C, and then sample the material to test its Marshall value; Step 9: The qualified cannon mud is packed into boxes in plastic bags by the molding machine and sent to the blast furnace for use.

[0005] The granular aggregate is any one of fused brown corundum, high-alumina bauxite, 20%-40% coke powder, silica, soft clay, silicon nitride, and silicon iron nitride particles, or a mixture of several of them; the aggregate filler is silicon carbide particles.

[0006] The proportion of 1-3 mm in the coarse fused brown corundum particles is less than 80%, and the proportion of particles less than 0.074 mm is greater than 80%. The chemical composition requirements are: Al2O3 ≥ 80%, Fe2O3 ≤ 2.0%, MgO+CaO ≤ 0.5%, water absorption rate ≤ 5%, and the refractoriness reaches 1770°C; the chemical composition requirements of the soft clay are: 26%-29% Al2O3, Fe2O3 ≤ 4%, R20 ≤ 2%, the moisture requirement is less than 5%, and the particle size requirement is less than 0.088 mm, with more than 95%.

[0007] The soft clay is any one of 8% Guangxi white mud or 10%-15% Suzhou clay fine powder or a mixture of the two.

[0008] The fine powder material is any one of sericite fine powder and SiC fine powder resistant to slag iron corrosion, or a mixture of the two.

[0009] The chemical composition of the sericite powder is required to be 71%-77% SiO2, 3%-7% R20, and the particle size is required to be greater than 90% less than 0.074mm.

[0010] The binder is any one or a mixture of modified tar, decrystallized anthracene oil and modified phenolic resin based on Al2O3-SiC-C.

[0011] The binder is one of a modified polymer and an environmentally friendly plastic liquid.

[0012] The additive is any one of 3b%-5b% Al2O3 fine powder and elemental silicon fine powder or a mixture of the two.

[0013] The expansion agent in step 6 is any one of 1-2 mm in particle size, 3a%-5a% of kyanite and 3 mm in critical particle size of pyroxene, or a mixture of the two.

[0014] The invention has the following beneficial effects: the invention is a method for preparing an environmentally friendly anhydrous taphole mud. In use, the invention selects appropriate amounts of kyanite, Guangxi mud, alumina micropowder and elemental silicon and combines other proportioning materials, and uses a modified polymer as a binder. When the modified polymer is used as a binder, no yellow smoke is generated during the use of the taphole mud, and the irritating odor generated is very small; and the environmentally friendly taphole mud has the characteristics of easy mud making, easy opening, long iron tapping time, small iron mouth expansion, and no pollution; no benzopyrene is detected in the environmentally friendly binder of the invention, and the developed taphole mud is used in a blast furnace, the taphole depth is stable at about 3m, and the taphole mud consumes 0.5kg·(t iron). -1 The length of the mud strips is increased, and the slag resistance of the cannon mud is improved; the cannon mud rolled by the invention has stable quality, good slag and iron erosion resistance, stable iron flow speed, and can continuously tap iron for more than 6 hours; the filling property of the cannon mud is good, and the bonding property between the new and old cannon mud is good, no iron seepage occurs, and no major accidents such as iron mouth fracture occur; the cannon mud has good quick drying and quick hardening properties, and the cannon can be pulled out within 30 minutes, thereby extending the life of the cannon mouth; the unit consumption of the foamed mud is low, which reduces the production cost; the present invention has the advantages of energy saving and environmental protection, convenience and durability, strong erosion resistance and good plasticity. DETAILED DESCRIPTION

[0015] The present invention is further described below. Example

[0016] The method for preparing an environmentally friendly anhydrous taphole mud comprises the following steps: Step 1: Prepare materials: weigh the granular aggregate, aggregate filler, fine powder, additives and binder according to the proportions. The weighing error shall not exceed 1%. Step 2: Drying: Heat the granular aggregate, aggregate filler, fine powder, additive and binder to 100°C respectively, stir and dehydrate at 0.5MPa, and stop heating when the Engler viscosity is 9 and the water content is less than 0.5wt%, and store at a constant temperature of 45°C for standby use; Step 3: Grinding: Put the granular aggregate, aggregate filler, fine powder and additives into the ball mill for grinding; Step 4: Crushing: Put the material ground in step 3 into an airflow superfine pulverizer for crushing; Step 5: Mixing: Add the crushed mixture in step 4 into the anhydrous cannon mud mixer and stir for 10 minutes to fully mix the materials; Step 6: Add the expansion agent and 2% of the binder into the anhydrous cannon mud mixer and mix with the mixture after the treatment in step 5, and continue stirring for 15 minutes; Step 7: The prepared mud is ground in a Φ1200×500mm mud mill; Step 8: After dry grinding and mixing for 3 minutes, add the remaining 98% of the binder, grind for another 35 minutes at a temperature range of 10°C, and then sample the material to test its Marshall value, which is controlled at 0.7MPA; Step 9: The qualified cannon mud is packed into boxes in plastic bags by the molding machine and sent to the blast furnace for use.

[0017] The granular aggregate is any one of fused brown corundum, high-alumina bauxite, 20% coke powder, soft clay, and silicon ferronitride particles, or a mixture of several of them; the aggregate filler is silicon carbide particles, which can improve the ability of the cannon mud to resist slag erosion and scouring. A certain amount of silicon carbide is added to the mud to fill the gaps between the main aggregate particles to form a refractory matrix, so that the mud has better slag resistance, high-temperature structural strength and thermal shock stability, and can improve its ability to resist slag erosion and scouring.

[0018] The proportion of 1mm in the coarse fused brown corundum particles is less than 80%, and the proportion of particles less than 0.074mm is greater than 80%. The chemical composition requirements are: Al2O3≥80%, Fe2O3≤2.0%, MgO+CaO≤0.5%, water absorption rate≤5%, and the refractoriness reaches 1770℃. A certain proportion of brown corundum is added to the anhydrous cannon mud to improve the cannon mud's resistance to slag iron scouring and chemical erosion of slag, as well as the high-temperature structural strength of the cannon mud; the chemical composition requirements of the soft clay are: 26%-29% Al2O3, Fe2O3≤4%, R20≤2%, the moisture requirement is less than 5%, and the particle size requirement is greater than 95% of particles less than 0.088mm.

[0019] The soft clay is 8% Guangxi white mud.

[0020] In this embodiment, the addition of Guangxi white mud can increase the plasticity of the cannon mud, and also has a significant effect on the strength and linear change of the cannon mud. As the amount of Guangxi mud added increases, the post-firing strength of the cannon mud increases, but the high-temperature flexural strength decreases, and the post-firing shrinkage of the cannon mud increases. Considering various indicators comprehensively, the amount of Guangxi mud added is more appropriate at about 8%.

[0021] The fine powder material is fine sericite powder.

[0022] In the present embodiment, sericite can widen the sintering temperature range of cannon mud. Since the sintering temperature of sericite is lower than that of clay, the cannon mud can dry and harden quickly, thus shortening the time for pulling out the gun after the cannon mud is plugged. The SiO2 content in sericite is relatively high, which can prevent the cannon mud from cracking in the iron mouth channel due to excessive shrinkage during firing. Due to the fine scaly structure of sericite, it can play a certain lubricating role, improve the rheological properties of the cannon mud, and make the cannon mud easy to extrude from the gun, thus greatly improving the operability. The sericite is added in the form of fine powder.

[0023] The chemical composition of the sericite powder is required to be 71%-77% SiO2, 3%-7% R20, and the particle size is required to be greater than 90% less than 0.074mm.

[0024] The binder is any one or a mixture of modified tar, decrystallized anthracene oil and modified phenolic resin based on Al2O3-SiC-C.

[0025] The additive is 3b%-5b% Al2O3 powder.

[0026] The expansion agent in step 6 is kyanite with a particle size of 1-2 mm and 3a%-5a%.

[0027] In this embodiment, kyanite is irreversibly transformed into mullite and free SiO2 at high temperature (1100-1650°C), and produces a volume expansion of 16%-18%; adding kyanite can make up for the shrinkage caused by sintering of cannon clay at high temperature. The particle size of kyanite is 1-2mm. As the amount of kyanite added increases, the post-firing shrinkage of the cannon clay gradually decreases. When the added amount exceeds 5a%, the shrinkage gradually increases. Therefore, the best amount of kyanite added is 5a%, which can effectively reduce the apparent porosity of the cannon clay.

[0028] The invention discloses a method for preparing an environment-friendly anhydrous taphole mud. In use, the invention selects appropriate amounts of kyanite, Guangxi mud, alumina micropowder and elemental silicon and combines other proportioning materials, and uses a modified polymer as a binder. When the modified polymer is used as a binder, no yellow smoke is generated during the use of the taphole mud, and the irritating odor generated is very small. Moreover, the environment-friendly taphole mud has the characteristics of easy mud making, easy opening, long iron tapping time, small iron mouth expansion, and no pollution. No benzopyrene is detected in the environment-friendly binder of the invention. The developed taphole mud is used in a blast furnace, the taphole depth is stable at about 3m, and the taphole mud consumes 0.5kg·(t iron). -1 The length of the mud strips is increased, and the slag resistance of the cannon mud is improved; the cannon mud rolled by the invention has stable quality, good slag and iron erosion resistance, stable iron flow speed, and can continuously tap iron for more than 6 hours; the filling property of the cannon mud is good, and the bonding property between the new and old cannon mud is good, no iron seepage occurs, and no major accidents such as iron mouth fracture occur; the cannon mud has good quick drying and quick hardening properties, and the cannon can be pulled out within 30 minutes, thereby extending the life of the cannon mouth; the unit consumption of the foamed mud is low, which reduces the production cost; the present invention has the advantages of energy saving and environmental protection, convenience and durability, strong erosion resistance and good plasticity. Example

[0029] The method for preparing an environmentally friendly anhydrous taphole mud comprises the following steps: Step 1: Prepare materials: weigh the granular aggregate, aggregate filler, fine powder, additives and binder according to the proportions. The weighing error shall not exceed 1%. Step 2: Drying: Heat the granular aggregate, aggregate filler, fine powder, additive and binder to 110°C respectively, stir and dehydrate at 0.6MPa, and stop heating when the Engler viscosity is 10 and the water content is less than 0.5wt%, and store at a constant temperature of 50°C for standby use; Step 3: Grinding: Put the granular aggregate, aggregate filler, fine powder and additives into the ball mill for grinding; Step 4: Crushing: Put the material ground in step 3 into an airflow superfine pulverizer for crushing; Step 5: Mixing: Add the crushed mixture in step 4 into the anhydrous cannon mud mixer and stir for 13 minutes to fully mix the materials; Step 6: Add the expansion agent and 3% of the binder into the anhydrous taphole mud mixer and mix with the mixture treated in step 5, and continue stirring for 20 minutes; Step 7: The prepared mud is ground in a Φ1200×500mm mud mill; Step 8: After dry grinding and mixing for 3 minutes, add the remaining 97% of the binder, grind for another 35 minutes at a temperature range of 20°C, and then sample the material to test its Marshall value, which is controlled at 0.71MPA; Step 9: The qualified cannon mud is packed into boxes in plastic bags by the molding machine and sent to the blast furnace for use.

[0030] The granular aggregate is any one of fused brown corundum, high-alumina bauxite, 30% coke powder, silica, soft clay, silicon nitride particles, or a mixture of several of them; the aggregate filler is silicon carbide particles.

[0031] In this embodiment, coke powder can increase the air permeability of the taphole clay, facilitating the volatilization of volatiles from the taphole clay. Coke powder is relatively brittle, and adding it appropriately can increase the drillability of the iron mouth taphole clay. At the same time, coke can produce a reducing atmosphere, protecting other carbon-containing components from oxidation and improving the corrosion resistance of the taphole clay. The appropriate amount of coke powder added is 20%-40%.

[0032] The proportion of 2mm in the coarse fused brown corundum particles is less than 80%, and the proportion of particles less than 0.074mm is greater than 80%. The chemical composition requirements are: Al2O3≥80%, Fe2O3≤2.0%, MgO+CaO≤0.5%, water absorption rate≤5%, and the refractoriness reaches 1770°C; the chemical composition requirements of the soft clay are: 26%-29% Al2O3, Fe2O3≤4%, R20≤2%, the moisture requirement is less than 5%, and the particle size requirement is less than 0.088mm, with more than 95%.

[0033] The soft clay is 10%-15% Suzhou clay fine powder.

[0034] In this embodiment, Suzhou clay has strong plasticity at room temperature. Adding a proper amount can make the cannon clay form a mushroom shape on the surface of the furnace, which can improve the bonding properties of new and old cannon clays, and is beneficial to the early sintering of the cannon clay to form a ceramic bond, thereby improving the early strength of the cannon clay. It is required to be added in the form of fine powder.

[0035] The fine powder material is SiC fine powder resistant to slag and iron corrosion.

[0036] In this embodiment, the addition of silicon carbide is to utilize its slag iron corrosion resistance to improve the slag iron corrosion resistance of the taphole mud, and also inhibit the oxidation of carbon-containing substances. The mechanism of silicon carbide's corrosion resistance is: SiC(s)+CO(g)→SiO(g)+2C(g) SiO(g)+CO(g)→SiO2(s)+C(s) Since the volume will increase accordingly during these reactions, further densifying the taphole mud and helping to reduce carbon oxidation and slag penetration, SiC should be added in the form of fine powder.

[0037] The binder is one of a modified polymer and an environmentally friendly plastic liquid.

[0038] In this embodiment, the raw material of the environmentally friendly plastic liquid binder itself contains a very small amount of carcinogenic substances PAHs, especially the B(a)P content is less than 30ppm, which meets the European environmental protection standards; the plastic liquid binder is characterized by environmental protection, high residual carbon, low viscosity, forming a carbonaceous network at high temperature, and improving corrosion resistance. The plastic liquid binder content in the cannon mud is less than 12% to have good plasticity; in addition, there is no unpleasant odor in the cannon mud production process, and no black, yellow and other harmful gases are generated during use, which is beneficial to the health of personnel engaged in cannon mud production and iron-making plant operators.

[0039] The additive is elemental silicon fine powder.

[0040] The expansion agent in step 6 is coke with a critical particle size of 3 mm.

[0041] In this embodiment, the use of calcined coke particles with a refractoriness higher than 1680°C can greatly increase the strength of the cannon clay, improve the resistance of the cannon clay to molten iron scouring, reduce the porosity of the cannon clay, and improve the volume stability of the general cannon clay. The critical particle size is 3mm.

[0042] The invention discloses a method for preparing an environment-friendly anhydrous taphole mud. In use, the invention selects appropriate amounts of kyanite, Guangxi mud, alumina micropowder and elemental silicon and combines other proportioning materials, and uses a modified polymer as a binder. When the modified polymer is used as a binder, no yellow smoke is generated during the use of the taphole mud, and the irritating odor generated is very small. Moreover, the environment-friendly taphole mud has the characteristics of easy mud making, easy opening, long iron tapping time, small iron mouth expansion, and no pollution. No benzopyrene is detected in the environment-friendly binder of the invention. The developed taphole mud is used in a blast furnace, the taphole depth is stable at about 3m, and the taphole mud consumes 0.5kg·(t iron). -1 The length of the mud strips is increased, and the slag resistance of the cannon mud is improved; the cannon mud rolled by the invention has stable quality, good slag and iron erosion resistance, stable iron flow speed, and can continuously tap iron for more than 6 hours; the filling property of the cannon mud is good, and the bonding property between the new and old cannon mud is good, no iron seepage occurs, and no major accidents such as iron mouth fracture occur; the cannon mud has good quick drying and quick hardening properties, and the cannon can be pulled out within 30 minutes, thereby extending the life of the cannon mouth; the unit consumption of the foamed mud is low, which reduces the production cost; the present invention has the advantages of energy saving and environmental protection, convenience and durability, strong erosion resistance and good plasticity. Example

[0043] The method for preparing an environmentally friendly anhydrous taphole mud comprises the following steps: Step 1: Prepare materials: weigh the granular aggregate, aggregate filler, fine powder, additives and binder according to the proportions. The weighing error shall not exceed 1%. Step 2: Drying: Heat the granular aggregate, aggregate filler, fine powder, additive and binder to 120°C respectively, stir and dehydrate at 0.7MPa, and stop heating when the Engler viscosity is 11 and the water content is less than 0.5wt%, and store at a constant temperature of 55°C for standby use; Step 3: Grinding: Put the granular aggregate, aggregate filler, fine powder and additives into the ball mill for grinding; Step 4: Crushing: Put the material ground in step 3 into an airflow superfine pulverizer for crushing; Step 5: Mixing: Add the crushed mixture in step 4 into the anhydrous cannon mud mixer and stir for 15 minutes to fully mix the materials; Step 6: Add the expansion agent and 5% of the binder into the anhydrous taphole mud mixer and mix with the mixed material after the treatment in step 5, and continue stirring for 30 minutes; Step 7: The prepared mud is ground in a Φ1200×500mm mud mill; Step 8: After dry milling and mixing for 4 minutes, add the remaining 95% of the binder, and mill for another 35 minutes at a temperature range of 30°C, then sample the material to test its Marshall value, which is controlled at 0.73MPA; Step 9: The qualified cannon mud is packed into boxes in plastic bags by the molding machine and sent to the blast furnace for use.

[0044] The granular aggregate is any one of fused brown corundum, high-alumina bauxite, 40% coke powder, silica, soft clay, silicon nitride, and silicon iron nitride particles, or a mixture of several of them; the aggregate filler is silicon carbide particles.

[0045] In the present embodiment, silicon nitride and silicon ferronitride have good thermal shock stability, chemical corrosion resistance, high strength, small high-temperature creep, and very low thermal expansion coefficient; the oxidation resistance temperature can reach 1400°C, and the maximum operating temperature in a reducing atmosphere can reach 1870°C; adding an appropriate amount of Si3N4 raw material to the cannon mud can improve the corrosion resistance and scour resistance of the cannon mud, can keep the iron outlet depth relatively stable, and is beneficial to extending the life of the furnace; using Si3N4 in combination with SiC to replace SiC, or using Fe-Si3N4 also has a good effect; as the furnace temperature increases, silicon nitride or Fe-Si3N4 reacts with the matrix to produce silicon carbide and escapes gas; it is beneficial to improve the strength of the cannon mud and appropriately increase the exhaust duct.

[0046] The proportion of 1-3 mm in the coarse fused brown corundum particles is less than 80%, and the proportion of particles less than 0.074 mm is greater than 80%. The chemical composition requirements are: Al2O3 ≥ 80%, Fe2O3 ≤ 2.0%, MgO+CaO ≤ 0.5%, water absorption rate ≤ 5%, and the refractoriness reaches 1770°C; the chemical composition requirements of the soft clay are: 26%-29% Al2O3, Fe2O3 ≤ 4%, R20 ≤ 2%, the moisture requirement is less than 5%, and the particle size requirement is less than 0.088 mm, with more than 95%.

[0047] The soft clay is a mixture of 8% Guangxi white mud or 10%-15% Suzhou clay fine powder.

[0048] The fine powder material is a mixture of sericite fine powder and SiC fine powder resistant to slag iron corrosion.

[0049] The chemical composition of the sericite powder is required to be 71%-77% SiO2, 3%-7% R20, and the particle size is required to be greater than 90% less than 0.074mm.

[0050] The binder is one of a modified polymer and an environmentally friendly plastic liquid.

[0051] The additive is a mixture of 3b%-5b% Al2O3 fine powder and elemental silicon fine powder.

[0052] In this embodiment, the addition of alumina powder increases the compressive strength and high-temperature flexural strength of the anhydrous cannon mud, but when the addition amount exceeds 5b%, the effect on the strength of the anhydrous cannon mud is not obvious, so the addition amount of alumina powder is selected to be 5b%; the addition of elemental silicon has a significant enhancing effect on the strength of the cannon mud, especially the high-temperature strength. The higher the high-temperature strength of the cannon mud, the better its erosion resistance, the smaller the hole expansion, and the longer the iron-tapping time. Since the opening capacity of each blast furnace opening machine is strong or weak, therefore, the appropriate amount of elemental silicon addition should be selected on the basis of alumina powder according to the blast furnace iron-tapping time requirements and the opening capacity of the opening machine; the addition of Al2O3 powder and elemental silicon fine powder mixed raw material (or its ultrafine powder mixed raw material) further improves the density and sintering performance of the prepared anhydrous cannon mud.

[0053] The expansion agent in step 6 is a mixture of kyanite with a particle size of 1-2 mm and 3a%-5a% and pyroxene with a critical particle size of 3 mm.

[0054] The invention discloses a method for preparing an environment-friendly anhydrous taphole mud. In use, the invention selects appropriate amounts of kyanite, Guangxi mud, alumina micropowder and elemental silicon and combines other proportioning materials, and uses a modified polymer as a binder. When the modified polymer is used as a binder, no yellow smoke is generated during the use of the taphole mud, and the irritating odor generated is very small. Moreover, the environment-friendly taphole mud has the characteristics of easy mud making, easy opening, long iron tapping time, small iron mouth expansion, and no pollution. No benzopyrene is detected in the environment-friendly binder of the invention. The developed taphole mud is used in a blast furnace, the taphole depth is stable at about 3m, and the taphole mud consumes 0.5kg·(t iron). -1 The length of the mud strips is increased, and the slag resistance of the cannon mud is improved; the cannon mud rolled by the invention has stable quality, good slag and iron erosion resistance, stable iron flow speed, and can continuously tap iron for more than 6 hours; the filling property of the cannon mud is good, and the bonding property between the new and old cannon mud is good, no iron seepage occurs, and no major accidents such as iron mouth fracture occur; the cannon mud has good quick drying and quick hardening properties, and the cannon can be pulled out within 30 minutes, thereby extending the life of the cannon mouth; the unit consumption of the foamed mud is low, which reduces the production cost; the present invention has the advantages of energy saving and environmental protection, convenience and durability, strong erosion resistance and good plasticity.

[0055] Table 1 Physical properties of taphole clay <![CDATA[Bulk density g / cm 3 > Compressive strengthMpa Flexural strengthMpa Porosity% Re-burning line change rate (1400℃×2h)% Maxia value Mpa 2.18 18 9.3 25.1 -0.089 0.728 The slag resistance was determined by the static crucible method, and the slag was taken from 2500m 3 Blast furnace water-washed slag, its chemical composition is shown in Table 2 Table 2 Chemical composition <![CDATA[Al2O3]]> <![CDATA[SiO2]]> CaO MgO <![CDATA[TiO2]]> <![CDATA[K2O]]> FeO 16.37 34.61 36.91 9.2 0.29 0.45 0.81 The environmentally friendly taphole mud of the present invention is used in a steel company with a capacity of 2000 m 3The blast furnace of was used for trial, and the blast furnace originally used tar-combined anhydrous taphole mud; the actual use shows that the environmentally friendly taphole mud has the characteristics of easy mud making, easy opening, small iron mouth expansion during iron tapping, long iron tapping time, and no yellow smoke during use; the use of the environmentally friendly taphole mud of the present invention and the original tar-combined anhydrous taphole mud of the blast furnace is compared in Table 3; Table 3 Comparison of the use of the present invention and the original tar taphole mud Average opening time / min Average tapping time / min Average iron tapping speed / (t / min) Yellow smoke Original tar taphole mud 6-8 92 4.75 serious Taphole mud of the present invention 4-6 92 4.13 none It can be seen from Table 3 that the environmentally friendly taphole clay of the present invention has the advantages of easy opening, long iron tapping time, small iron mouth expansion and no pollution compared with the taphole clay originally used in the blast furnace.

Claims

1. Environmentally friendly anhydrous taphole mud preparation method, Features: The method comprises the following steps: Step 1: Prepare materials: weigh the granular aggregate, aggregate filler, fine powder, additives and binder according to the proportions. The weighing error shall not exceed 1%. Step 2: Drying: Heat the granular aggregate, aggregate filler, fine powder, additive, and binder, stir, and dehydrate them. When the water content is less than 0.5wt%, stop heating and store them at a constant temperature for later use. Step 3: Grinding: Put the granular aggregate, aggregate filler, fine powder and additives into the ball mill for grinding; Step 4: Crushing: Put the material ground in step 3 into an airflow superfine pulverizer for crushing; Step 5: Mixing: Add the crushed mixture in step 4 into the waterless taphole mud mixer and stir for 10 to 15 minutes to fully mix the materials; Step 6: Add the expansion agent and 2% of the binder into the anhydrous taphole mud mixer and mix with the mixed material after the treatment in step 5, and continue stirring for 15 to 30 minutes; Step 7: The prepared mud is ground in a Φ1200×500mm mud mill; Step 8: After dry milling and mixing for 3-4 minutes, add the remaining 98% of the binder, and mill for another 35 minutes at a temperature range of 10-30°C, and then sample the material to test its Marshall value; Step 9: The qualified cannon mud is packed into boxes in plastic bags by the molding machine and sent to the blast furnace for use.

2. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 1, Features: The granular aggregate is any one of fused brown corundum, high-alumina bauxite, 20%-40% coke powder, silica, soft clay, silicon nitride, and silicon iron nitride particles, or a mixture of several of them; the aggregate filler is silicon carbide particles.

3. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 2, Features: The proportion of 1-3 mm coarse particles of the fused brown corundum is less than 80%, and the proportion of particles less than 0.074 mm is greater than 80%. The chemical composition requirements are: Al 2 O 3 ≥80%,Fe 2 O 3 ≤2.0%, MgO+CaO≤0.5%, water absorption ≤5%, refractoriness reaches 1770℃; the chemical composition requirements of the soft clay are: 26%-29%Al 2 O 3 , Fe 2 O 3 ≤4%, R 2 0≤2%, moisture requirement is less than 5%, particle size requirement is less than 0.088mm and greater than 95%.

4. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 3, Features: The soft clay is any one of 8% Guangxi white mud or 10%-15% Suzhou clay fine powder or a mixture of the two.

5. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 1, Features: The fine powder material is any one of sericite fine powder and SiC fine powder resistant to slag iron corrosion, or a mixture of the two.

6. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 5, Features: The chemical composition of the sericite powder fine powder requires 71%-77% Si. 2 , 3%-7%R 2 0, the particle size requirement is less than 0.074mm and more than 90% of them.

7. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 1, Features: The binder is Al 2 O 3 -SiC-C based modified tar, decrystallized anthracene oil, modified phenolic resin, any one or a mixture of several of them.

8. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 1 or 7, Features: The binder is one of a modified polymer and an environmentally friendly plastic liquid.

9. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 1, Features: The additive is 3b%-5b% Al 2 O 3 Any one of micro powder, elemental silicon fine powder or a mixture of the two; various additives and or ultra-fine powder additives further improve its density and sintering performance 10. The method for preparing the environmentally friendly anhydrous taphole mud according to claim 1, Features: The expansion agent in step 6 is any one of 1-2 mm in particle size, 3a%-5a% of kyanite and 3 mm in critical particle size of pyroxene, or a mixture of the two.