KR100492223B1 - Refractory Mortar Containing Carbon - Google Patents

Abstract

An object of the present invention is to provide a carbon-containing refractory mortar having excellent anti-oxidation and good disassembly of the joint and the back of the carbon-containing refractory brick.

Accordingly, the present invention is based on extrapolation of the inorganic antioxidants B ₂ O ₃ and B ₂ O ₃ salts alone or in combination in a refractory material having a particle size of 1 mm or less and a mixture of amorphous carbon of 10:90 to 70:30. It provides a carbon-containing refractory mortar characterized in that it contains 20 to 20% by weight and the oil extrapolated from 10 to 40% by weight.

Description

Refractory Mortar Containing Carbon}

The present invention relates to a carbon-containing refractory mortar for preventing oxidation of carbon-containing refractory bricks used to prevent oxidation of joints and backs of various carbon-containing refractory bricks used in steelmaking and steelmaking furnaces.

More specifically, in the present invention, the inorganic antioxidants B ₂ O ₃ and B ₂ O ₃ salts alone or in combination in the refractory material of the magnesia powder having a particle size of 1mm or less and the amorphous carbon of 10:90 ~ 70:30 The present invention relates to a carbon-containing refractory mortar which is capable of preventing oxidation of the joint and the back surface of the carbon-containing refractory brick by containing 3 to 20% by weight of extrapolation and 10 to 40% by weight of oil.

In general, a variety of carbon-containing refractory bricks such as MgO-C, Al ₂ O ₃ -C and Al ₂ O ₃ -MgO-C are used in various urinaries such as converters and timing 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 brick due to the generation of water vapor during preheating, and in particular, carbon-containing refractory bricks used for moving surfaces and permanent lining Dissolution is poor due to reaction fusion with the semi-permanent refractory brick.

Japanese Patent Application Laid-Open No. Hei 2-59476 uses a hot repair spray material mainly composed of tar, clay oil, carbon, and basic aggregates, but this technique is used for backside 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.

Accordingly, the present invention was devised to overcome the above disadvantages, and the inorganic antioxidants B ₂ O ₃ and B ₂ in a refractory material having a particle size of 1 mm or less of magnesia powder and amorphous carbon in a mixing ratio of 10:90 to 70:30. Refractory carbon-containing refractory and excellent disintegration of O ₃ salts alone or in combination with 3 to 20% by weight of extrapolation basis and 10 to 40% by weight of oil with extrapolation. The purpose is to provide mortar.

In order to achieve the object as described above, the present invention, the carbon-containing refractory mortar of the present invention is an inorganic antioxidant B ₂ in the refractory material of the magnesia powder having a particle size of 1 mm or less and the amorphous carbon of 10:90 ~ 70:30 The O ₃ and B ₂ O ₃ salts alone or in combination, characterized in that 3 to 20% by weight of extrapolation and 10 to 40% by weight of oil extrapolated.

The particle size of the magnesia powder used in the carbon-containing refractory mortar should be 1 mm or less. When the particle size of the magnesia powder is 1 mm or more, the gap gap of the joint part of the carbon-containing refractory brick becomes large, thereby increasing the damage of the joint part, and the filling on the back side is poor, and the rear anti-oxidation effect is lowered.

There is no particular limitation on the magnesia powder, and any of ordinary melting and sintering magnesia 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 carbon-containing refractory brick fireproof composition, the mixing ratio of the spinel powder and the amorphous carbon defined above should be 10:90 to 70:30 by weight. When the content of magnesia powder is 10% by weight or less, the magnesia powder is insufficient and the filling of carbon-containing refractory mortar is poor, and the antioxidant effect is lowered. When the content of magnesia powder is 70% by weight or more, the content of magnesia powder is excessive, and the antioxidant effect of the carbon-containing refractory brick is lowered.

B ₂ O ₃ oxides or B ₂ O ₃ salts are used as inorganic antioxidants for the purpose of preventing oxidation of amorphous carbon in carbon-containing refractory mortars. B ₂ O ₃ oxide or boric acid, or more chloride-based, fluoride-based, and sulfide, such as B ₂ O ₃ based salts as not not particularly limited to a purity of 95% to Fig sufficiently exert mubang one effect of addition by using the commercially available powder It is preferable.

The amount alone or in combination of B ₂ O ₃ oxide and B ₂ O ₃ salt added to the mixture of magnesia powder and amorphous carbon defined above should be 3 to 10% by weight extrapolated.

When the addition amount of the B ₂ O ₃ -based inorganic antioxidant is extrapolated to 3% by weight or less, the antioxidant effect of amorphous carbon is insignificant, and the antioxidant effect on the joint or the back of the carbon-containing refractory brick is reduced. In addition, when the amount of the B ₂ O ₃ -based inorganic antioxidant added is more than 10% by weight, carbon-containing refractory bricks are eroded during use, resulting in damage of the refractory bricks.

The amount of oil extrapolated to the mixture of magnesia powder and amorphous carbon defined above should be 10-40% by weight. When the content of oil added by extrapolation is less than 10% by weight, the oil is insufficient and the refractory mortar containing carbon is not applied. When the content of oil is more than 40% by weight by extrapolation, the content of oil is excessive due to excessive oil content. Refractory mortar flows down, which causes difficulties in construction.

The oil used in the present invention is not particularly limited, but kerosene or heavy oil-based petroleum is preferred because of its relatively low flammability and relatively high residual carbon content.

Hereinafter, the present invention will be described in detail through examples.

Example Comparative example One 2 3 One 2 3 4 5 6 7 Magnesia Particle Size (mm) -One -One -One 1.5 -One -One -One -One -One -One Magnesia: Mixing ratio of amorphous carbon (weight ratio) 20:80 40:60 70:30 50:50 5:95 80:20 30:70 50:50 50:50 20:80 Inorganic antioxidants (extrapolated, weight%) B ₂ O ₃ 3 7 10 One - - One - 5 - H ₃ BO ₃ - 3 - 2 10 3 - 15 - 7 Addition amount of oil (extrapolation, weight%) 10 40 30 40 10 30 20 30 5 50 Thickness of backside oxide layer ¹⁾ (mm) 3 One 2 25 15 18 15 27 - - Joint damage index ²⁾ 0.1 0.2 0.1 1.4 1.4 1.5 1.9 2.1 - - Construction possibility Good Good Good Good Good Good Good Good Impossible Impossible

1) Average thickness of oxide layer on the back surface based on 50mm residual amount of MgO-C quality refractory brick after using 156ch

2) Comparative Damage Index of MgO-C Quality Refractory Brick Joint Based on Comparative Example 2 after Using 156ch

The inorganic antioxidants B ₂ O ₃ and B ₂ O ₃ salts (H ₃ BO ₃ ) alone were added to the refractory material having a mixing ratio of 10:90 to 70:30 of the magnesia powder having the particle size of 1 mm or less and the amorphous carbon. Alternatively, the carbon-containing refractory mortar prepared by adding 3 to 20% by weight of the extrapolation standard and 10 to 40% by weight of the oil extrapolated to the MgO-C quality refractory brick for the Timing Ladle Slag Line was applied. 1 to 3 were obtained. Moreover, the refractory mortar containing carbon was manufactured in the range outside the Example, and Comparative Examples 1-7 were obtained.

Extrapolation of inorganic antioxidants B ₂ O ₃ and B ₂ O ₃ salts (H ₃ BO ₃ ) alone or in combination to a refractory material having a particle size of 1 mm or less and a mixture of amorphous carbon of 10:90 to 70:30 Examples 1 to 3, which is a carbon-containing refractory mortar prepared by containing 3 to 20% by weight and 10 to 40% by weight of the oil by extrapolation, have achieved the object of the present invention, but Comparative Examples 1 to 1 outside the scope of the present invention. 7 showed a weak antioxidant effect of carbon-containing refractory bricks.

According to the carbon-containing refractory deodorization according to the present invention as described above, by providing a refractory composition for the oxidation of carbon-containing refractory bricks to improve the oxidation resistance of the joint and the back of the carbon-containing refractory bricks, Excellent effect.

Claims (2)

Magnesia powder having a particle size of 1mm or less and amorphous carbon in a weight ratio of 10:90 to 70:30 mixed with the refractory material; B ₂ O ₃ and B ₂ O ₃ salt added to the refractory material alone or in combination of 3 to 20% by weight extrapolation; Kerosene or heavy oil petroleum oil is added to the refractory material by extrapolation based on 10 to 40% by weight; Carbon-containing refractory mortar comprising a. delete