CN111004022A

CN111004022A - Semi-steel tank slag line repairing material and preparation method thereof

Info

Publication number: CN111004022A
Application number: CN201911299650.XA
Authority: CN
Inventors: 青光红; 罗天军; 陈超; 边程军; 高同昌; 赵杰; 高亮; 邓小兵; 蒋发燕
Original assignee: Gangcheng Group Liangshan Ruihai Industry Co ltd
Current assignee: Gangcheng Group Liangshan Ruihai Industry Co ltd
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2020-04-14

Abstract

The invention belongs to the technical field of semi-steel tank refractory materials, and particularly relates to a semi-steel tank slag line repairing material and a preparation method thereof. Aiming at the problems that the service life of the semi-steel tank slag line layer working layer bricks is shorter than that of other working layer bricks, and the safety risk is easily caused, the invention provides a semi-steel tank slag line repairing material which comprises the following raw materials: by weight percentage, 33-36% of alumina, 26-31% of zirconia alumina, 16-22% of silicon carbide particles, 3-5% of aluminum oxide micro powder, 2-3% of Guangxi white mud, 2-3% of bentonite, 2-3% of micro silicon powder, 5-6% of cement, 2-3% of carbon black, 0.1-0.15% of sodium hexametaphosphate, 0.8-1% of borax and 0.05-0.08% of explosion-proof fibers. The repairing material disclosed by the invention has the characteristics of good construction smearing performance, excellent slag corrosion resistance, stable thermodynamic performance, long service life and the like, can effectively resist the corrosion of slag to the slag line brick of the semi-steel tank, reduces the off-line minor repair times, and has important practical significance.

Description

Semi-steel tank slag line repairing material and preparation method thereof

Technical Field

The invention belongs to the technical field of semi-steel tank refractory materials, and particularly relates to a semi-steel tank slag line repairing material and a preparation method thereof.

Background

At present, the main process of steel making is a process of firstly extracting vanadium and then desulfurizing, molten iron is conveyed to a vanadium extraction converter through a hot metal ladle, vanadium extraction efficiency and vanadium slag grade are controlled by adding a vanadium extraction coolant and other auxiliary materials, the treated molten steel is generally called semisteel, the semisteel is conveyed to desulfurization through a semisteel tank for desulfurization and slag extraction treatment, passivation lime and passivation magnesium powder are injected to carry out high-efficiency desulfurization in the desulfurization process, a desulfurization spray gun is inserted into the bottom of the semisteel tank for injection at a depth of about 500mm, the injection process is about 20-25min, calcium sulfide, magnesium sulfide, calcium silicate and other slag are generated by the reaction of the lime and the magnesium powder and S, C, Si in the semisteel during the period and float upwards, magnesium steam and carbon monoxide formed at high temperature can promote foaming and stirring effects of the slag, but the generated magnesium sulfide can promote viscosity of the slag to increase and is not beneficial to slag extraction, in order to solve the condition, and a certain amount of sodium salt is added in the blowing process to adjust the viscosity of the molten slag, and after the desulfurization is finished, the semisteel tank conveys the semisteel to a converter for slagging treatment, so that one turnover of the semisteel is completed. Therefore, the semisteel tank is very important in the semisteel smelting process.

The semi-steel tank is built by several blocks, one is the replacement of a permanent layer, the permanent layer is divided into a wall-covering permanent layer and a bottom-covering permanent layer, the one-time replacement period is generally 1500-time plus 1600 times, and the other is the replacement of the bricks of the working layer, the bricks of the working layer are made of Al₂O₃The SiC-C brick is used for resisting complex slag components of molten iron, the required use times are 700 and 800 times, the third time is pouring of refractory materials of a tank nozzle, and the service life is usually requiredThe number of the reaction solutions was determined to be about 450.

Because of the blowing and stirring process in the desulfurization process, the desulfurization slag and the sodium salt compound can be more obviously washed on the slag line layer of the semisteel tank, and generally, the service life of the working layer bricks on the slag line layer of the semisteel tank is about 20 times shorter than that of the working layer bricks in other ranges. Therefore, the service life of the semi-steel tank slag line layer working layer brick is short, the service life of the whole working layer brick is shortened, and certain safety risk is realized.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the service life of the semi-steel tank slag line layer working layer bricks is shorter than that of other working layer bricks, and the problem of safety risk is easily caused.

The technical scheme for solving the technical problems comprises the following steps: provides a semi-steel tank slag line repairing material. The raw materials comprise: by weight percentage, 33-36% of alumina, 26-31% of zirconia alumina, 16-22% of silicon carbide particles, 3-5% of aluminum oxide micro powder, 2-3% of Guangxi white mud, 2-3% of bentonite, 2-3% of micro silicon powder, 5-6% of cement, 2-3% of carbon black, 0.1-0.15% of sodium hexametaphosphate, 0.8-1% of borax and 0.05-0.08% of explosion-proof fibers.

In the semi-steel tank slag line repairing material, 16-18% of alumina particles with the particle size of 3-8 mm in the alumina and 17-18% of alumina powder with the particle size of less than 0.074mm in the alumina are contained.

In the semi-steel tank slag line repairing material, 8-10% of zircon corundum particles with the particle size of 1-3 mm, 8-10% of zircon corundum particles with the particle size of 0.074-1 mm and 10-11% of zircon corundum powder with the particle size of less than 0.074mm are contained in the zircon corundum.

In the semi-steel tank slag line repairing material, 3-5% of silicon carbide particles with the particle size of 1-3 mm, 7-9% of silicon carbide particles with the particle size of 0.074-1 mm and 6-8% of silicon carbide fine powder with the particle size of less than 0.074mm are contained in silicon carbide.

Wherein, in the semi-steel tank slag line repairing material, the grain diameter of the aluminum oxide micro powder is less than 0.005 mm.

In the semi-steel tank slag line repairing material, the particle sizes of Guangxi white mud, bentonite, micro silicon powder, cement and carbon black are all less than 0.074 mm.

The semi-steel tank slag line repairing material comprises the following chemical components: by weight percent, Al₂O₃≥50％，ZrO₂≥5％，SiC≥15％，C≥1.5％。

In the semi-steel tank slag line repairing material, the sum of the water contents of the raw materials of the repairing material is less than or equal to 1%.

In the semi-steel tank slag line repairing material, the alumina contains more than or equal to 88% of alumina; the zirconia corundum is zirconia corundum containing more than or equal to 25 percent of zirconia and more than or equal to 50 percent of alumina; the silicon carbide is silicon carbide containing more than or equal to 90 percent of silicon carbide; the aluminum oxide micro powder is aluminum oxide containing more than or equal to 99 percent of aluminum oxide; the Guangxi white mud contains SiO₂≥49％，Al₂O₃More than or equal to 32 percent of Guangxi white mud; the bentonite is sodium-based bentonite with montmorillonite content of 85-90%; the carbon black is carbon black with the carbon content of more than or equal to 85 percent; the cement is calcium aluminate cement containing more than or equal to 50 percent of aluminum oxide and with the model of CA-70; the micro silicon powder is silicon powder containing more than or equal to 94 percent of silicon dioxide; the sodium hexametaphosphate meets the requirements of HG/T2837-1997; the corresponding brand of the explosion-proof fiber is JX-3-3; the borax meets the requirements of GB/T537-1997.

The invention also provides a preparation method of the semi-steel tank slag line repairing material, which comprises the following steps:

weighing the raw materials according to the weight ratio, and stirring and mixing uniformly.

In the preparation method of the semi-steel tank slag line repairing material, the stirring time is more than or equal to 5 min.

Compared with the prior art, the invention has the beneficial effects that:

the semi-steel tank slag line repairing material provided by the invention has the characteristics of good construction smearing performance, excellent slag corrosion resistance, stable thermodynamic performance, long service life and the like, can effectively resist the corrosion of slag to semi-steel tank slag line bricks, reduces the off-line minor repair times, and has important practical significance.

Detailed Description

The invention provides a semisteel tank slag line repairing material, which comprises the following components: by weight percentage, 33-36% of alumina, 26-31% of zirconia alumina, 16-22% of silicon carbide particles, 3-5% of aluminum oxide micro powder, 2-3% of Guangxi white mud, 2-3% of bentonite, 2-3% of micro silicon powder, 5-6% of cement, 2-3% of carbon black, 0.1-0.15% of sodium hexametaphosphate, 0.8-1% of borax and 0.05-0.08% of explosion-proof fibers.

The semisteel ladle slag line repairing material designed by the invention is mainly used for repairing 2-8 cm pits, so that the particle size of the raw material of the repairing material is set within the range, and is mainly determined by the size and the volume of the repaired pits. Different raw materials are set to different particle sizes and keep continuity, so that the fire resistance can be improved.

Wherein, in the semi-steel tank slag line repairing material,the alumina contains more than or equal to 88 percent of aluminum oxide; the zirconia corundum is zirconia corundum containing more than or equal to 25 percent of zirconia and more than or equal to 50 percent of alumina; the silicon carbide is silicon carbide containing more than or equal to 90 percent of silicon carbide; the aluminum oxide micro powder is aluminum oxide containing more than or equal to 99 percent of aluminum oxide; the Guangxi white mud contains SiO₂≥49％，Al₂O₃More than or equal to 32 percent of Guangxi white mud; the bentonite is sodium-based bentonite with montmorillonite content of 85-90%; the carbon black is carbon black with the carbon content of more than or equal to 85 percent; the cement is calcium aluminate cement containing more than or equal to 50 percent of aluminum oxide and with the model of CA-70; the micro silicon powder is silicon powder containing more than or equal to 94 percent of silicon dioxide; the sodium hexametaphosphate meets the requirements of HG/T2837-1997; the corresponding brand of the explosion-proof fiber is JX-3-3; the borax meets the requirements of GB/T537-1997.

The repairing material is mainly used for improving the material of the erosion part of the working layer of the semi-steel tank, and basic components consistent with the bricks of the working layer are selected in order to improve the sintering performance, the slag erosion resistance, the oxidation resistance, the thermal shock resistance and the like; furthermore, in order to improve the slag corrosion resistance, the oxidation resistance, the thermal shock resistance, the sintering performance and the like, special raw materials are selected for performance improvement.

The base components of the patching material of the invention are as follows: brick series Al₂O₃SiC to C material; the alumina aggregate mainly provides a basic framework support for the repairing material and is a main source for providing aluminum oxide; the silicon carbide aggregate and the fine powder have the characteristics of corrosion resistance of semisteel acid slag, high temperature resistance, high strength, good heat-conducting property, impact resistance and the like; the carbon black has ductility, is easy to permeate into the whole mending material, has a special space structure and is not easy to form a slag coating.

Further, the method can be used for preparing a novel materialThe invention also adds the zirconia corundum, can provide part of alumina and ZrO thereof₂The high-viscosity glass phase is formed at high temperature, plays a role in promoting sintering on reducing thermal stress damage, slag penetration resistance and thermal state strength, and can prevent high-temperature oxidation of carbon black and silicon carbide by proper addition, so that the comprehensive performance is further enhanced.

The semi-steel tank slag line repairing material is mainly prepared by respectively providing Al with aluminum, silicon carbide and carbonaceous materials in the selection of raw materials₂O₃The SiC and the C adopt the zirconia corundum to provide the aluminum oxide and the zirconia with various granularities to resist the corrosion of alkaline slag, can effectively improve the slag corrosion resistance of the coating material, and the silica fume and the Guangxi white mud provide SiO₂It can form mullite phase with alumina at 1200 deg.c in the presence of sintering promoter to raise the heat strength and heat shock resistance of the coating material, and has early construction strength of refractory cement, alumina powder and α Al₂O₃The micro powder, the micro silicon powder, the Guangxi white mud and the sodium hexametaphosphate are used as binding agents, the viscosity of the coating is adjusted, the smoothness of construction coating is improved by adopting carbon black, the slag corrosion resistance is improved, the wettability of the coating is improved by adopting bentonite, the conduction of water vapor in the baking process is improved by adopting explosion-proof fibers, the apparent porosity is reduced, the sintering temperature of the coating can be reduced by adopting borax, and the sintering strength is effectively improved.

The aggregate component is set to be 40-50%, and the main reason is that the adhesion of the coating material is reduced and the coating material is loosened due to too much aggregate, and the high-temperature mechanical property is influenced due to the weak frame part of the coating material due to too little aggregate. Meanwhile, the proportion of the micro powder is set to be 50-60%, so that ideal adhesion performance can be achieved.

The following examples are given to further illustrate the embodiments of the present invention, but are not intended to limit the scope of the present invention to the examples.

The physical and chemical indexes of alumina, zirconia alumina, silicon carbide, carbon black, activated alumina micropowder, silica fume and CA70 cement used in the examples are shown in Table 1.

TABLE 1 example physical and chemical indexes of raw materials of semi-steel tank slag line repairing material

The prepared semisteel ladle slag line repairing material meets the physicochemical indexes shown in the table 2:

TABLE 2 physical and chemical indexes of semi-steel tank slag line repairing material

Example 1 preparation of a semisteel ladle slag line repair material according to the present invention

The adopted raw materials are shown in the table 3, after the raw materials are qualified, the raw materials are weighed, stirred and packaged, then sampling detection is carried out, the physical and chemical indexes of the semisteel tank slag line repairing material are shown in the table 4, and the materials are transported to a semisteel tank cold repair operation area for use after being qualified.

TABLE 3 semisteel ladle slag line repair material formulation 1

TABLE 4 EXAMPLE 1 physicochemical indexes of semi-steel tank slag line repair material

Item	The detection result is%
		Al₂O₃，％	52.75
ZrO₂，％	7.56
		SiC，％	18.8
Volume density (110 ℃ C.. times.24 h), g/cm³	2.6
		Flexural strength (1200 ℃ is multiplied by 3h), MPa	4.3
The rate of change of the dead weight line (1200 ℃ C.. times.3 h)%	-0.2

In the embodiment, the semi-steel tank slag line repairing material is smeared on a semi-steel tank slag line brick part, 5 tons of semi-steel tank slag line repairing material in a semi-steel tank cold repair area is sent to the semi-steel tank cold repair area at this time, smearing data and online data of 3 painted semi-steel tanks are collected, and compared with 3 semi-steel tanks not smeared with the slag line repairing material, the smearing performance of 3 test semi-steel tanks is superior, the adhesion rate reaches over 90%, no material collapse occurs in the maintenance process, the crack phenomenon occurs, the online use times are respectively 19 times, 20 times and 23 times, the average time is 20.6 times, the use requirements of users can be met, and the slag line part brick can basically be consistent with the corrosion resistance of other parts after being smeared.

Example 2 preparation of a semisteel ladle slag line repair material according to the present invention

The adopted raw materials are shown in the table 5, after the raw materials are qualified, the raw materials are weighed, stirred and packaged, then sampling detection is carried out, the physical and chemical indexes of the semisteel tank slag line repairing material are shown in the table 6, and the semisteel tank slag line repairing material is transported to a semisteel tank cold repair operation area for use after being qualified.

TABLE 5 semi-steel ladle slag line repair mix formulation 2

TABLE 6 EXAMPLE 2 physicochemical indexes of semi-steel tank slag line repairing material

Item	The detection result is%
		Al₂O₃，％	52.97
ZrO₂，％	7.56
		SiC，％	18.8
Volume density (110 ℃ C.. times.24 h), g/cm³	2.55
		Flexural strength (1200 ℃ is multiplied by 3h), MPa	4.1
The rate of change of the dead weight line (1200 ℃ C.. times.3 h)%	-0.33

In the embodiment, the semi-steel tank slag line repairing material is smeared on a semi-steel tank slag line brick part, the semi-steel tank slag line repairing material is sent to a semi-steel tank cold repair area for 4.5 tons at this time, smearing data and online data after smearing 3 semi-steel tanks are collected, the semi-steel tank slag line repairing material is compared with 3 semi-steel tanks which are not smeared with the slag line repairing material, the smearing performance of 3 test semi-steel tanks is superior, the adhesion rate reaches more than 92%, no material collapse occurs in the maintenance process, the crack phenomenon occurs, the online use times are respectively 18 times, 24 times and 21 times, the average number of times is 21 times, the use requirements of users can be met, and the slag line part brick can be basically consistent with the corrosion resistance of other parts after being smeared.

The results of the embodiment show that the semi-steel tank slag line repairing material has the advantages of excellent construction performance, long service life, capability of effectively reducing the repair times of the semi-steel tank and wide application prospect when applied to the semi-steel tank slag line.

Claims

1. The semi-steel tank slag line repairing material is characterized by comprising the following raw materials: by weight percentage, 33-36% of alumina, 26-31% of zirconia alumina, 16-22% of silicon carbide particles, 3-5% of aluminum oxide micro powder, 2-3% of Guangxi white mud, 2-3% of bentonite, 2-3% of micro silicon powder, 5-6% of cement, 2-3% of carbon black, 0.1-0.15% of sodium hexametaphosphate, 0.8-1% of borax and 0.05-0.08% of explosion-proof fibers.

2. The semisteel ladle slag line repair mix according to claim 1, characterized in that: in the bauxite, 16-18% of bauxite particles with the particle size of 3-8 mm and 17-18% of bauxite powder with the particle size of less than 0.074mm are contained.

3. The semisteel ladle slag line repair mix according to claim 1, characterized in that: in the zirconia corundum, 8-10% of zirconia corundum particles with the particle size of 1-3 mm, 8-10% of zirconia corundum particles with the particle size of 0.074-1 mm and 10-11% of zirconia corundum powder with the particle size of less than 0.074mm are contained.

4. The semisteel ladle slag line repair mix according to claim 1, characterized in that: in the silicon carbide, 3-5% of silicon carbide particles with the particle size of 1-3 mm, 7-9% of silicon carbide particles with the particle size of 0.074-1 mm and 6-8% of silicon carbide fine powder with the particle size of less than 0.074mm are contained.

5. The semisteel ladle slag line repair mix according to claim 1, characterized in that: the grain diameter of the aluminum oxide micro powder is less than 0.005 mm.

6. The semisteel ladle slag line repair mix according to claim 1, characterized in that: the particle sizes of the Guangxi white mud, the bentonite, the micro silicon powder, the cement and the carbon black are all less than 0.074 mm.

7. The semisteel ladle slag line repair mix according to claim 1, characterized in that: the chemical components are as follows: by weight percent, Al₂O₃≥50％，ZrO₂≥5％，SiC≥15％，C≥1.5％。

8. The semisteel ladle slag line repair mass of claim 1, wherein at least one of the following is satisfied:

the alumina contains more than or equal to 88 percent of aluminum oxide;

the zirconia corundum is zirconia corundum containing more than or equal to 25 percent of zirconia and more than or equal to 50 percent of alumina;

the silicon carbide is silicon carbide containing more than or equal to 90 percent of silicon carbide;

the aluminum oxide micro powder is aluminum oxide containing more than or equal to 99 percent of aluminum oxide;

the Guangxi white mud contains SiO₂≥49％，Al₂O₃More than or equal to 32 percent of Guangxi white mud;

the bentonite is sodium-based bentonite with montmorillonite content of 85-90%;

the carbon black is carbon black with the carbon content of more than or equal to 85 percent;

the cement is calcium aluminate cement containing more than or equal to 50 percent of aluminum oxide and with the model of CA-70;

the micro silicon powder is silicon powder containing more than or equal to 94 percent of silicon dioxide;

the sodium hexametaphosphate meets the requirements of HG/T2837-1997;

the corresponding brand of the explosion-proof fiber is JX-3-3;

the borax meets the requirements of GB/T537-1997.

9. The preparation method of the semisteel ladle slag line repairing mix as defined in any one of claims 1 to 8, which is characterized by comprising the following steps:

10. The preparation method of the semisteel ladle slag line repairing mix according to claim 9, characterized by comprising the following steps: the stirring time is more than or equal to 5 min.