Torpedo ladle lining smearing repair material, preparation method and use method

Abstract

The invention discloses a torpedo ladle lining smearing repair material, a preparation method and a use method. The torpedo ladle lining smearing repair material comprises three Al2O3-containing usedrefractory reclaimed materials with different granularities and two brown fused alumina with different granularities, and the surfaces of the three Al2O3-containing used refractory reclaimed materialswith different granularities and the two brown fused alumina with different granularities are coated or partially coated with nano carbon films; wherein the thickness of the nano carbon film is 20-200 nanometers, and the fixed carbon content of the nano carbon film is more than or equal to 90%. The repair material has the characteristics of low raw material cost, wide renewable resource source, excellent thermal shock resistance, high interface bonding strength of a repairing layer, strong slag iron erosion resistance, simplicity and convenience in preparation and application and the like. Bymeans of the repair material, the service life of the torpedo ladle is prolonged, the consumption and maintenance cost of torpedo ladle refractory materials are reduced, the heat preservation and insulation performance of the torpedo ladle refractory material lining is improved, and the temperature drop of molten iron is reduced.

Description

technical field [0001] The invention belongs to the technical field of carbon-containing refractory lining smearing repair material, and in particular relates to a torpedo tank lining smearing repair material, a preparation method and a use method. Background technique [0002] The torpedo tank has become one of the main thermal equipment for the transportation of molten iron between the iron-making blast furnace and the steel-making converter in domestic and foreign iron and steel enterprises due to its advantages of large molten iron loading capacity, high transportation efficiency, good thermal insulation performance, lower temperature of molten iron, and long service life. , the middle section is cylindrical, and the two ends are conical truncated cones. The shape is similar to a torpedo, so it is called a torpedo tank. Due to the irregular shape of the torpedo tank, the refractory lining of the torpedo tank is complicated to build and the production cost is high; becaus...

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Problems solved by technology

The Chinese patent "Wang Liwang, Chang Zhengqin, Zhu Guoping, A hot gunning material for torpedo tanks and its preparation method, application publication number CN104829250A", discloses a hot gunning material, which includes 20-20 parts by mass. 30 parts of high alumina bauxite of 3-5mm, 10-15 parts of high-alumina bauxite of 1-3mm, 20-25 parts of silicon carbide of 0-1mm, 10-20 parts of high-alumina bauxite not larger than 200 mesh, 10- 20 parts of calcium aluminate cement, 4 to 6 parts of flake graphite powder, 2 to 5 parts of resin powder, 1 to 3 parts of asphalt powder not larger than 180 mesh, 0.01 to 0.02 parts of explosion-proof fiber, 0.01 to 0.02 parts of silicon aluminum nitride, the above After the raw material is mixed with 8-10% water evenly, spraying machine is used for gunning construction, so as to realize online thermal gunning of torpedo tanks, and overcome the shortcomings of the existing gunning materials for thermal repair of torpedo tanks, which are brittle and easy to crack

However, the above-mentioned technologies all use natural mineral clinker and artificial synthetic raw materials as the main raw materials, which leads to high preparation costs of repairing materials and affects the economics of practical application. Lining repair spray paint and its preparation method and use method, application publication number: CN104744060A" discloses a torpedo tank lining repair spray paint using recycled refractory material as the main raw material, its preparation method and use method, and the mass percentage of raw materials For: 35-45% of waste torpedo bricks, 20-25% of brown corundum, 12-18% of silicon carbide powder, 10-15% of waste iron trench material powder, 4-6% of pure calcium aluminate cement, 3-5% of additives %, 0.5-1.5% anti-oxidant, and 0.1-0.5% superplasticizer, 0.02-0.05% anti-explosion agent, the critical particle size is 5mm; the preparation method is: mix the above-mentioned raw materials in a strong mixer according to the ratio for 2-4min The spray paint can be obtained; the method of use is: add 5-7% of the total mass of water to the spray paint, mix it in a strong mixer for 1-2 minutes and then spray; after spraying, bake it at 500-700°C After 2 to 3 hours, the torpedo tank can be used normally; the use of waste materials reduces production and use costs, which is conducive to environmental protection

[0004] According to the above literature and patent reports, the existing gunning material and repair castable technology is mainly aimed at Al 2 o 3 —Maintenance and repair of partial damage of SiC-C refractory brick working lining, through cleaning the surface of residual bricks in the lining and partial repair with unshaped refractory materials, to maintain the service life of torpedo tanks and reduce the removal of refractory bricks during minor and medium repairs of torpedo tanks Digging and repairing maintenance, shortening repair and maintenance time, reducing the baking temperature and time after repairing, reducing the cost of repairing refractory materials; it can be seen that none of the prior art involves torpedo tank Al 2 o 3 —Important oxidation damage problem of SiC—C refractory brick working lining

Although the oxidation damage of carbon-containing refractories has been highly valued by industry scholars, a series of carbon-containing refractory antioxidants and anti-oxidation coatings have been developed successively, and excellent results have been achieved in prolonging the service life of carbon-containing refractories in actual production applications. However, according to the data "Tian Baoshan, Bayi Iron and Steel 260t Torpedo Tank Operation and Maintenance Practice, Metallurgical Series, 2013, No3", the torpedo tank after overhaul baked for a long time, up to 145 hours, and the highest baking temperature was greater than 1000 °C , the turnover rate is 1.8-2.8 times / day, and the turnover and empty tank time is long. Therefore, during the baking and service process of the torpedo tank before it is put into operation, Al 2 o 3 ——SiC—C refractory brick working lining oxidation problem is unavoidable, and leads to serious problem of oxidation spalling

However, due to the long baking time and high baking temperature of the torpedo can, the anti-oxidation coating is thin, Al 2 o 3 —SiC—C refractory brick working lining surface oxidation is still unavoidable. After testing, the thickness of the decarburization layer is about 20mm

In addition, due to the low melting point of the existing anti-oxidation coating technology, the coating is melted and lost after loading molten iron, which cannot realize the anti-oxidation effect of the torpedo tank when it is empty during service

In addition, the existing torpedo tank lining repair material technology mainly uses calcium aluminate cement as the binder, which has poor wettability to carbon-containing refractory materials, and it is difficult to form a tight bond with the surface of carbon-containing refractory materials. When repairing, it is necessary to control the degree of surface cleaning, and there must be residual decarburization layer, otherwise it will affect the repair effect

[0005] Based on the above, it can be seen that for the torpedo tank Al 2 o 3 —SiC—C refractory brick working lining baking and service process empty tank oxidative decarburization and molten iron, slag penetration erosion and other issues, although they have attracted the attention of industry scholars, but have not attracted attention, how to prevent torpedo tanks Al 2 o 3 ——SiC—C refractory brick working lining oxidation can also play a role of repair and maintenance, further research is needed; in addition, for the molten iron tank that undertakes the transportation and pretreatment of molten iron, its function is the same as that of a torpedo tank. In order to effectively extend the Service life, working lining bricks have also developed from high alumina bricks to aluminum carbon bricks and aluminum silicon carbide carbon bricks. Therefore, there are also baking oxidation of working lining bricks, oxidative decarburization of empty tanks during service, and penetration erosion of molten iron and slag. and other issues; since the damage of the working lining bricks during the service process of the molten iron tank can be clearly and visually observed, and the maintenance is relatively simple and easy, therefore, the baking and oxidation of the carbon-containing working lining bricks and the oxidative decarburization of the empty tank during the service process and its service process The repair and maintenance of damage has not received widespread attention, resulting in a short service life of the hot metal tank, especially the KR desulfurization hot metal tank with one tank to the bottom. The service life of the hot metal tank is only about 1 / 5 of that of the torpedo tank. Lined iron tanks, it is even more necessary to carry out technical research on anti-oxidation and timely repair and maintenance of damage throughout the service

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