Anhydrous converter gunning mix

Abstract

The invention discloses an anhydrous converter gunning mix and a preparation method thereof, and relates to the technical field of steelmaking. Comprising 15%-25% of 3-1 magnesia, 20%-30% of 1-0 magnesia, 8%-13% of liquid phenolic resin (externally added), 25%-35% of 200 fused magnesia, 1%-3% of 200-mesh aluminum powder, 3%-5% of asphalt powder, 2%-5% of crystalline flake graphite and 5%-10% of solid resin powder. The anhydrous converter gunning material can be smoothly sprayed without water by using graphite as a lubricant, and the resin and asphalt powder are added, so that the resin and the asphalt are quickly softened and separated out to play a bonding role after the anhydrous converter gunning material is sprayed out, and the anhydrous converter gunning material can be quickly bonded on a furnace wall; the strength of carbon-bonded bulk materials at high temperature is higher than that of water-bonded bulk materials, so that the durability is improved, and the loss of the converter lining is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of steelmaking, and in particular relates to a waterless converter gunning material. Background Art

[0002] During the operation and production of steel mills, converters are widely used as containers for steelmaking. The converter lining is divided into two structures: thermal insulation layer and working layer. The thermal insulation layer mainly plays the role of isolating heat conduction and reducing the temperature of the furnace shell; the working layer plays the role of receiving molten steel. The main material of the working layer is MgO-C refractory material. During the converter smelting process, the lining is severely affected by thermal shock, slag erosion, and molten steel scouring, resulting in deep pits. The two sides of the ear shaft of the molten pool are restricted by the structure of the converter and the direction of the furnace shaking, and cannot be repaired with feeding materials. Only gunning materials can be used for repair;

[0003] The existing gunning materials are all semi-dry gunning materials. The main raw materials are dead-burned magnesia, sodium hexametaphosphate, calcium oxide, clay and other raw materials. A large amount of water needs to be added during construction. However, the working lining magnesia carbon bricks will become powdery when exposed to water, resulting in peeling of the furnace lining bricks and poor repair effect. In addition, the binder and water reducer used in the semi-dry gunning materials are low-melting materials, which can greatly reduce the refractoriness of magnesia and reduce the life of the gunning materials. Frequent gunning operations are required, which seriously affects production efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a waterless converter gunning material with a simple structure and reasonable design in order to solve the above problems.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0006] A method for preparing a waterless converter gunning material, comprising 15%-25% of 3-1 magnesia, 20%-30% of 1-0 magnesia, 8%-13% of liquid phenolic resin (external addition), 25%-35% of 200 fused magnesia, 1%-3% of 200 mesh aluminum powder, 3%-5% of asphalt powder, 2%-5% of flake graphite, and 5%-10% of solid resin powder;

[0007] The specific steps include:

[0008] Preparation of Mixture Component A:

[0009] S1, put 3-1 magnesia particles, 1-0 magnesia particles and liquid phenolic resin (external addition) into a mixer for the first mixing;

[0010] S2, adding 200 molten magnesia, 200 mesh aluminum powder and asphalt powder into the mixer for a second mixing, and discharging to obtain component A;

[0011] S3, subjecting component A to natural health care;

[0012] Preparation of gunning material:

[0013] S4, putting the cured component A, solid resin powder, and liquid phenolic resin (external addition) into a mixer for a third mixing;

[0014] S5, adding 200 mesh magnesia sand and flake graphite into the mixer and mixing for the fourth time to obtain a mixed material;

[0015] S6. The mixed material is naturally cured to obtain the gunning material.

[0016] Further, in step S1, the liquid phenolic resin (external addition) is 3%-5%, and the 200 fused magnesia is 20%-25%.

[0017] Furthermore, the first mixing time and the third mixing time are 2-4 minutes, the second mixing time is 3-5 minutes, and the fourth mixing time is 3-6 minutes.

[0018] Furthermore, the mixing temperature is lower than 40°C.

[0019] Furthermore, in steps S3 and S6, the health-preserving time is 10 hours.

[0020] Furthermore, the mixer is a planetary mixer.

[0021] As a further optimization scheme of the present invention, the present invention also provides a waterless converter gunning material, which is prepared by the above-mentioned method for preparing a waterless converter gunning material.

[0022] The present invention has at least the following beneficial effects: the present invention utilizes graphite as a lubricant and can be sprayed smoothly without water. By replacing the binder with resin and asphalt powder, the refractoriness of magnesia is improved, so that after the converter waterless gunning material is sprayed out, the resin and asphalt quickly soften and precipitate to play a bonding role, and can be quickly bonded to the furnace wall. At high temperatures, the strength of the carbon-bonded bulk material is higher than that of the water-bonded bulk material, thereby improving its durability, reducing the loss of the converter lining, reducing the number of gunning times, and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a flow chart of the steps of the present invention. DETAILED DESCRIPTION

[0024] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0025] like Figure 1 As shown:

[0026] Example 1

[0027] A method for preparing anhydrous converter gunning material:

[0028] 24% magnesium oxide content is 95% 3-1 magnesia grains, 30% magnesium oxide content is 95% 1-0 magnesia grains plus 1% liquid phenolic resin (external addition) put into planetary mixer and mix for 2-4 minute, and then add 10% magnesium oxide content is 97% 200 order fused magnesia, 3% 200 order aluminum powder, 4% 180 order high temperature asphalt powder and mix for the second time, mixing time is 3-5 minute, discharge obtains component A, and component A is carried out natural health for 10 hours;

[0029] The cured component A, 10% solid resin powder and 2% liquid phenolic resin (external addition) are put into a planetary mixer for the third mixing, and the mixing time is 2-4 minutes; then 12% 200 mesh fused magnesia and 4% flake graphite are added to the planetary mixer for the fourth mixing, and the mixing time is 3-6 minutes to obtain a mixture; the mixture is naturally cured for 10 hours to obtain a gunning material; during the entire mixing process, the temperature is controlled below 40°C to prevent the resin from hardening prematurely due to excessive temperature and uneven powder wrapping.

[0030] Example 2

[0031] A method for preparing anhydrous converter gunning material:

[0032] 23% magnesium oxide content is 95% 3-1 magnesia grains, 30% magnesium oxide content is 95% 1-0 magnesia grains plus 2% liquid phenolic resin (external addition) put into planetary mixer and mix for 2-4 minute, and then add 10% magnesium oxide content is 97% 200 order fused magnesia, 3% 200 order aluminum powder, 4% 180 order high temperature asphalt powder and mix for the second time, mixing time is 3-5 minute, discharge obtains component A, and component A is carried out natural health for 10 hours;

[0033] The cured component A, 10% solid resin powder and 2% liquid phenolic resin (external addition) are put into a planetary mixer for the third mixing, and the mixing time is 2-4 minutes; then 12% 200 mesh fused magnesia and 4% flake graphite are added to the planetary mixer for the fourth mixing, and the mixing time is 3-6 minutes to obtain a mixture; the mixture is naturally cured for 10 hours to obtain a gunning material; during the entire mixing process, the temperature is controlled below 40°C to prevent the resin from hardening prematurely due to excessive temperature and uneven powder wrapping.

[0034] Example 3

[0035] A method for preparing anhydrous converter gunning material:

[0036] 23% magnesium oxide content is 95% 3-1 magnesia grains, 31% magnesium oxide content is 95% 1-0 magnesia grains plus 2% liquid phenolic resin (external addition) put into planetary mixer and mix for 2-4 minute, and then add 10% magnesium oxide content is 97% 200 order fused magnesia, 3% 200 order aluminum powder, 3% 180 order high temperature asphalt powder and mix for the second time, mixing time is 3-5 minute, discharge obtains component A, and component A is carried out natural health for 10 hours;

[0037] The cured component A, 10% solid resin powder and 3% liquid phenolic resin (external addition) are put into a planetary mixer for the third mixing, and the mixing time is 2-4 minutes; then 11% 200 mesh fused magnesia and 4% flake graphite are added to the planetary mixer for the fourth mixing, and the mixing time is 3-6 minutes to obtain a mixture; the mixture is naturally cured for 10 hours to obtain a gunning material; during the entire mixing process, the temperature is controlled below 40°C to prevent the resin from hardening prematurely due to excessive temperature and uneven powder wrapping.

[0038] Example 4

[0039] A method for preparing anhydrous converter gunning material:

[0040] 22% magnesium oxide content is 95% 3-1 magnesia grains, 31% magnesium oxide content is 95% 1-0 magnesia grains plus 2% liquid phenolic resin (external addition) put into planetary mixer and mix for 2-4 minute, and then add 10% magnesium oxide content and be 97% 200 order fused magnesia, 3% 200 order aluminum powder, 3% 180 order high temperature asphalt powder and mix for the second time, mixing time is 3-5 minute, discharge obtains component A, and component A is carried out natural health care 10 hours;

[0041] The cured component A, 12% solid resin powder and 3% liquid phenolic resin (external addition) are put into a planetary mixer for the third mixing, and the mixing time is 2-4 minutes; then 11% 200 mesh fused magnesia and 3% flake graphite are added to the planetary mixer for the fourth mixing, and the mixing time is 3-6 minutes to obtain a mixture; the mixture is naturally cured for 10 hours to obtain a gunning material; during the entire mixing process, the temperature is controlled below 40°C to prevent the resin from hardening prematurely due to excessive temperature and uneven powder wrapping.

[0042] It should be noted that the planetary mixer is equipped with a bottom turntable, which can provide more uniform stirring and mixing effects, ensure that the components in the gunning material are fully mixed, and reduce the unevenness of the material.

[0043] Table 1 shows the proportion of each component in Examples 1-4:

[0044] Table 1

[0045]

[0046] The present invention performs performance tests on the gunning materials prepared in Examples 1-4, specifically including porosity test, bulk density test, pressure resistance test and MgO proportion test;

[0047] In Examples 1-4, a certain amount of gunning material samples were taken and dried. The volume of the samples was measured with a measuring cylinder, recorded as Vs, and the samples were weighed, recorded as M. The air in the samples was removed by a gas displacement instrument, and the change in gas volume was measured to obtain the measured volume of the samples, recorded as Vm. The porosity P was calculated by the following formula:

[0048] P=(Vs-Vm) / Vs*100%

[0049] The volume density ρ is calculated by the following formula:

[0050]

[0051] Pressure test: Take two samples of the same size in each of Examples 1-4, and place them in a drying oven for drying. Fix the two dried samples in pressure testing machines respectively, set the temperature of one pressure testing machine to 110°C, apply pressure continuously, and check whether the samples have cracks, deformation or other signs of damage after 24 hours; set the temperature of the other pressure testing machine to 1450°C, apply pressure continuously, and check whether the samples have cracks, deformation or other signs of damage after 3 hours.

[0052] MgO proportion test: In Examples 1-4, each weight is M 1 The sample is ground into fine powder using a pulverizer to ensure uniformity, and then the powder sample is dissolved in appropriate hydrochloric acid to remove other components, the solution is filtered to remove insoluble matter, the filtrate is heated and sodium hydroxide is added to precipitate MgO, and the precipitation is washed to remove impurities, usually washed with distilled water for multiple times, the precipitate is filtered and dried at 105°C to constant weight, the dried precipitate is weighed, and the mass M is recorded. 2 The MgO content C is calculated by the following formula:

[0053]

[0054] The test results are shown in Table 2:

[0055] Table 2

[0056]

[0057]

[0058] According to the test results, it can be seen that the gunning material prepared in Example 4 has the lowest porosity, and low porosity helps to improve the density and wear resistance of the material, thereby enhancing the protection of the furnace lining, reducing the loss and penetration of the furnace lining, and improving the high temperature resistance; the gunning material prepared in Example 4 has the highest body density and can better resist the erosion of furnace charge and slag, thereby reducing the loss of the furnace lining. High body density materials usually have better thermal stability and high temperature resistance, which helps to maintain stable performance in high temperature environments; and the pressure resistance is the strongest under the conditions of 110℃×24h and 1450℃×3h, which means that the material maintains good structural stability and strength at high temperatures, thereby better supporting furnace operations. Therefore, Example 4 is the optimal implementation scheme.

[0059] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A method for preparing anhydrous converter gunning material, characterized in that: Including 15%-25% 3-1 magnesia, 20%-30% 1-0 magnesia, 8%-13% liquid phenolic resin (external addition), 25%-35% 200 fused magnesia, 1%-3% 200 mesh aluminum powder, 3%-5% asphalt powder, 2%-5% flake graphite, 5%-10% solid resin powder; The specific steps include: Preparation of Mixture Component A: S1, put 3-1 magnesia particles, 1-0 magnesia particles and liquid phenolic resin (external addition) into a mixer for the first mixing; S2, adding 200g of fused magnesia, 200 mesh aluminum powder and asphalt powder into the mixer for a second mixing, and discharging to obtain component A; S3, subjecting component A to natural health care; Preparation of gunning material: S4, putting the cured component A, solid resin powder, and liquid phenolic resin (external addition) into a mixer for a third mixing; S5, adding 200 mesh fused magnesia and flake graphite into the mixer and mixing for the fourth time to obtain a mixed material; S6. The mixed material is naturally cured to obtain the gunning material.

2. The method for preparing anhydrous converter gunning material according to claim 1, characterized in that: In step S1, the liquid phenolic resin (external addition) is 3%-5%, and the 200 fused magnesia is 20%-25%.

3. The method for preparing anhydrous converter gunning material according to claim 2, characterized in that: The first and third mixing times are 2-4 minutes, the second mixing time is 3-5 minutes, and the fourth mixing time is 3-6 minutes.

4. The method for preparing anhydrous converter gunning material according to claim 3, characterized in that: The mixing temperature is below 40°C.

5. The method for preparing anhydrous converter gunning material according to claim 4, characterized in that: In steps S3 and S6, the health-preserving time is 10 hours.

6. The method for preparing anhydrous converter gunning material according to claim 5, characterized in that: The mixer is a planetary mixer.

7. A waterless converter gunning material, characterized in that: It is prepared according to the method for preparing a waterless converter gunning material according to any one of claims 1 to 6.

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