KR100601086B1 - Refractory mortar composition for basic refractory brick - Google Patents

Abstract

The present invention relates to a refractory mortar composition for a basic refractory brick, and an object thereof is to prevent oxidation of a joint and a back surface of a carbon-containing refractory brick, and a basic refractory brick having excellent dismantling property of a carbon-containing refractory brick after use. To provide a refractory mortar composition for. To this end, the refractory mortar composition for the basic refractory brick according to the present invention is composed of Al, Mg, and Si in a refractory material in which a magnesia powder having a particle size of 1 mm or less and amorphous carbon are mixed in a weight ratio of 20:80 to 70:30. At least one metal powder selected from the group and an antioxidant mixed with a boric acid in a weight ratio of 5:95 to 90:10 are extrapolated to 1 to 10 wt%, and the oil is extrapolated to 10 to 40 wt%. .

Refractory mortar, magnesia, metal powder

Description

Refractory mortar for basic refractory bricks}

The present invention relates to a refractory mortar composition for a basic refractory brick, and more particularly, to a carbon-containing refractory mortar composition for a basic refractory brick having excellent performance of preventing oxidation of a joint and a back surface of a carbon-containing refractory brick. .

In general, carbon-containing refractory bricks such as Al ₂ O ₃ -C and Al ₂ O ₃ -MgO-C are used in a variety of urinary tracts such as converters and teaming ladles. These carbon-containing refractory bricks are excellent in corrosion resistance to molten steel or slag, but when used, oxidation is involved in the joints and the back of the refractory bricks, resulting in a decrease in furnace life due to deterioration of the refractory bricks.

Water-based mortar used for carbon-containing refractory bricks deteriorates the characteristics of the refractory bricks due to the generation of water vapor during preheating, and in particular when used on the back, carbon-containing refractory bricks used for movable surfaces and permanent lining or semi permanent permanent There is a disadvantage in that disassembly is poor due to reaction fusion with bricks.

Japanese Patent Application Laid-Open No. 2-59476 uses a hot repair spray material mainly composed of tar, clay oil, carbon and basic aggregates, but this technology is used for back oxidation of carbon-containing refractory bricks. As a fireproof material which prevents this, there exists a disadvantage that it cannot use due to the fall of workability.

The present invention is to solve the problems as described above, the purpose is to prevent the oxidation of the joint and the back of the carbon-containing refractory bricks, as well as the fire retardant mortar for basic refractory bricks excellent in disassembly of the carbon-containing refractory bricks after use It is to provide a composition.

In order to achieve the object as described above, the refractory mortar composition for the basic refractory brick according to the present invention is a refractory material mixed with a magnesia powder having a particle size of 1 mm or less and amorphous carbon in a weight ratio of 20:80 to 70:30, At least one metal powder selected from the group consisting of Al, Mg and Si and an antioxidant mixed with a boric acid in a weight ratio of 5:95 to 90:10 are extrapolated to 1 to 10% by weight, and the oil is extrapolated to 10 to 40% % Is included.

Hereinafter, the refractory mortar composition for the basic refractory brick according to the present invention will be described in detail.

The particle size of the magnesia powder used in the carbon-containing refractory mortar composition for the basic refractory brick should be 1 mm or less. This is because, when the particle size of the magnesia powder exceeds 1 mm, the gap gap of the joint part of the carbon-containing refractory brick is increased to increase the damage of the joint part, and the filling at the back is poor, and the rear anti-oxidation effect is lowered.

There is no particular limitation on the magnesia powder, and a normal magnesia powder may be used, but in order to minimize the influence of impurities, the magnesia powder is preferably at least 95% pure.

Since the particle size of amorphous carbon is generally 1 mm or less, there is no particular limitation on the particle size, and in order to minimize the influence of impurities, the particle size is preferably 95% or more.

In the refractory mortar composition for the basic refractory brick, the mixing ratio of the magnesia powder and the amorphous carbon defined above should be 20:80 to 70:30 by weight. If the content of the magnesia powder is less than 20% by weight, the magnesia powder is insufficient and the filling of the carbon-containing refractory mortar composition is poor and the antioxidant effect is lowered. On the other hand, when the content of the magnesia powder exceeds 70% by weight, the content of the magnesia powder is excessive, which lowers the antioxidant effect of the carbon-containing refractory brick.

In the refractory mortar composition for basic refractory bricks, metal powders of Al, Mg, and Si used for the purpose of preventing oxidation of amorphous carbon are not particularly limited and commercially available ones may be used, but the effect of adding metal powders is not limited. In order to sufficiently exhibit the particle size, the particle size is preferably 50 μm or less, and in order to suppress the reaction by impurities, the purity is preferably 95% or more.

Boric acid used for the purpose of preventing oxidation of amorphous carbon in carbon-containing refractory mortar compositions for basic refractory bricks is not particularly limited and commercially available ones may be used, but purity 95 may be used to suppress reactions due to impurities. It is preferable that it is% or more.

The mixing ratio of the at least one metal powder and boric acid selected from the metal powders of Al, Mg and Si added to the mixture of magnesia powder and amorphous carbon defined above and extrapolation is 5:95 to 90:10 and 1 to 10, respectively. It should be weight percent. When the addition ratio of the metal in the mixture of the metal powder and boric acid is less than 5, the antioxidation effect of the joint wear and the back surface of the carbon-containing basic refractory brick decreases. When the addition ratio of the metal in the mixture of the metal powder and the boric acid exceeds 90, the basic refractory brick Due to excessive expansion of the carbon-containing refractory mortar composition for use, the antioxidant effect of joint wear and back of the basic refractory brick is reduced.

When the addition amount of the mixture of the metal powder and boric acid defined above is extrapolated to less than 1% by weight, the antioxidant effect of amorphous carbon is weak, and the antioxidant effect of the joint or the back surface of the carbon-containing refractory brick is reduced, and the mixture of the metal powder and boric acid is reduced. When the extrapolation exceeds 10% by weight, the B ₂ O ₃ oxide produced in boric acid and the oxide in the carbon-containing refractory brick react with each other to produce a low melting point compound, or excessive expansion of the refractory mortar causes damage to the refractory brick containing carbon. do.

Hereinafter, the present invention will be described in more detail with reference to Examples.

Examples 1 to 3

In Examples 1 to 3, as shown in Table 1, at least one metal selected from Al, Mg, and Si metal powders in a refractory material having a mixing ratio of magnesia powder having a particle size of 1 mm or less and amorphous carbon of 20:80 to 70:30 The carbon-containing refractory mortar composition for the basic refractory brick was prepared by adding 1 to 10% by weight and 10 to 40% by weight of an oil by adding an antioxidant having a mixing ratio of powder and boric acid at 5:95 to 90:10.

The prepared refractory mortar composition for the basic refractory brick was applied to the MgO-C refractory brick for the Timing Ladle Slag Line, and the back surface was based on the residual amount of the MgO-C refractory brick after the use of 156ch of 50 mm. The average oxide layer thickness was measured, and the comparative damage index of the MgO-C quality refractory brick joint was measured after using 156ch, and the results were shown in Table 1.

In addition, in Comparative Examples 1 to 9, as shown in Table 2, a refractory mortar composition was manufactured in a range outside the scope of the present invention, and the thickness, joint damage index, and workability of the back oxide layer were measured in the same manner as in Example. The results are shown in Table 2.

Example 1 Example 2 Example 3 Magnesia particle size (mm) 1 or less 1 or less 1 or less Magnesia: amorphous carbon (weight ratio) 20:80 40:60 70:30 Metal powder: Boric acid (weight ratio) 5:95 90:10 70:30 Addition amount of metal powder and boric acid mixture (extrapolation, weight%) 10 5 One Added amount of oil (extrapolated, weight%) 10 40 30 Back oxide layer thickness (mm) 0.5 2 3 Joint Damage Index 0.1 0.2 0.1 Construction possibility Good Good Good

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9 Magnesia particle size (mm) 1.5 1 or less 1 or less 1 or less 1 or less 1 or less 1 or less 1 or less 1 or less Magnesia: amorphous carbon (weight ratio) 50:50 10:90 80:20 70:30 30:70 30:70 40:60 50:50 20:80 Metal powder: Boric acid (weight ratio) 60:40 50:50 40:60 1:99 99: 1 50:50 50:50 40:60 60:40 Addition amount of metal powder and boric acid mixture (extrapolation, weight%) 5 5 5 One 10 15 0.5 7 2 Added amount of oil (extrapolated, weight%) 40 10 30 30 20 20 20 5 50 Back oxide layer thickness (mm) 25 18 17 16 15 35 32 - - Joint Damage Index 1.4 1.2 1.3 1.5 1.7 1.5 1.8 - - Construction possibility Good Good Good Good Good Good Good No construction No construction

As shown in Table 1, in Examples 1 to 3 of the present invention, the object of the present invention was achieved, while in Comparative Examples 1 to 9, the antioxidant effect of the carbon-containing refractory brick was weak as shown in Table 2. .

As described above, the refractory mortar composition according to the present invention has the effect of enhancing the oxidation resistance of the joint and the back of the basic refractory brick.

Claims (1)

Refractory material in which magnesia powder having a particle size of 1 mm or less and amorphous carbon are mixed in a weight ratio of 20:80 to 70:30; An antioxidant in which at least one metal powder selected from the group consisting of Al, Mg, and Si and boric acid are mixed at a weight ratio of 5:95 to 90:10; And Contains oil, 1 to 10% by weight of the antioxidant is extrapolated to the refractory material, and 10 to 40% by weight of the oil extrapolated refractory mortar composition for a refractory brick.