Calcium oxide slag based on adsorption of furnace lining and application thereof

Abstract

This invention relates to a composite calcium oxide slag based on furnace lining adsorption and its application, belonging to the field of protective slag technology. The composite calcium oxide slag of this invention comprises the following raw materials in parts by weight: CaO 48-52 parts, Al2O3 35-40 parts, MgO 5-8 parts, and metallic aluminum powder 1-3 parts. The raw materials are pre-melted and mixed to obtain the composite calcium oxide slag. Before pre-melting and mixing, alumina and metallic aluminum powder are ball-milled, and the aluminum powder is embedded in the alumina matrix in the form of nanocrystals, improving the stability of the composite calcium oxide slag. By utilizing the trace amounts of metallic aluminum pre-embedded in the slag, a rough structure is generated in situ on the surface of the magnesium-aluminum spinel furnace lining, thereby enhancing the mechanical anchoring and chemical adsorption of the dynamic reaction film, reducing the film formation temperature, and greatly increasing the film coverage.

Description

Technical Field

[0001] This invention belongs to the field of protective slag technology, and relates to a composite calcium oxide slag based on furnace lining adsorption and its application. Background Technology

[0002] High-temperature alloys are widely used in the manufacture of high-end components due to their excellent resistance to creep, fatigue, oxidation and hot corrosion. The sources of impurities in high-temperature alloys mainly include the master alloy, vacuum environment, crucible, shell, ceramic core and gating system. Therefore, the melting and preparation process of high-temperature alloys has a significant impact on the alloy properties.

[0003] Currently, vacuum induction melting is the main method for preparing most high-temperature alloys. Crucibles, as containers for vacuum induction melting of high-temperature alloys, are mainly classified into three types: MgO, CaO, and Al2O3. Among them, CaO has the functions of removing sulfur and phosphorus from molten steel and reducing oxygen content, and has advantages such as high melting point, stable thermodynamic properties, and low cost and availability. Coating existing furnace linings (such as magnesium aluminum spinel) with a calcium oxide-based coating can reduce production costs. However, due to the differences in thermal expansion coefficients and sintering characteristics between the two, it is prone to cracking and peeling under high-temperature thermal shock, leading to coating failure and contamination of the melt. In view of the above problems, this invention proposes a method based on furnace lining adsorption of composite calcium oxide slag and its application, making further optimizations based on existing technologies to solve the problem of calcium oxide-based coating peeling. Summary of the Invention

[0004] This invention relates to a composite calcium oxide slag based on furnace lining adsorption and its application, belonging to the field of protective slag technology. The composite calcium oxide slag of this invention comprises the following raw materials in parts by weight: CaO 48-52 parts, Al2O3 35-40 parts, MgO 5-8 parts, and metallic aluminum powder 1-3 parts. The raw materials are pre-melted and mixed to obtain the composite calcium oxide slag. Before pre-melting and mixing, alumina and metallic aluminum powder are ball-milled, and the aluminum powder is embedded in the alumina matrix in the form of nanocrystals, improving the stability of the composite calcium oxide slag. By utilizing the trace amounts of metallic aluminum pre-embedded in the slag, a rough structure is generated in situ on the surface of the magnesium-aluminum spinel furnace lining, thereby enhancing the mechanical anchoring and chemical adsorption of the dynamic reaction film, reducing the film formation temperature, and greatly increasing the film coverage.

[0005] The objective of this invention can be achieved through the following technical solutions: A composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 48-52 parts CaO, 35-40 parts Al2O3, 5-8 parts MgO, and 1-3 parts metallic aluminum powder.

[0006] Furthermore, the preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder, and then the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

[0007] Furthermore, the particle size of the mixed powder is 10-20 nm, the heating and melting temperature is 2860-2880 °C, and the particle size of the composite calcium oxide slag is 0.1-0.5 mm.

[0008] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a four-stage heating method, and the impurities that float to the top of the melt are removed.

[0009] Furthermore, the preheating temperature in step (1) is 700-800℃, and the mass ratio of the composite calcium oxide slag to the alloy material is 0.2-2:100.

[0010] Further, the four-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 800-850℃; the second stage is heating and holding, where the holding temperature is 900-1000℃; the third stage is heating and holding, where the holding temperature is 1200-1500℃; and the fourth stage is heating and holding, where the holding temperature is 1550-1580℃.

[0011] Furthermore, the heating rate and holding time of the first stage are 10-20℃ / s and 3-5min, respectively, and the heating rate and holding time of the second stage are 30-50℃ / s and 1-3min, respectively.

[0012] Furthermore, the heating rate and holding time of the third stage are 30-50℃ / s and 10-15min, respectively, and the heating rate and holding time of the fourth stage are 10-20℃ / s and 8-10min, respectively.

[0013] The beneficial effects of this invention are: This invention uses CaO, Al2O3, MgO, and metallic aluminum powder as raw materials. The raw materials are pre-melted and mixed to obtain composite calcium oxide slag. Before pre-melting and mixing, alumina and metallic aluminum powder are ball-milled. The aluminum powder is embedded in the alumina matrix in the form of nanocrystals to improve the stability of the composite calcium oxide slag. By utilizing the trace amount of metallic aluminum pre-embedded in the slag, a rough structure is generated in situ on the surface of the magnesium-aluminum spinel furnace lining, thereby enhancing the mechanical anchoring and chemical adsorption of the dynamic reaction film, reducing the film formation temperature, and greatly increasing the film coverage. Detailed Implementation

[0014] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with embodiments, is provided below.

[0015] The alloy material involved in this invention is Inconel 718 alloy.

[0016] Example 1 A composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 48 parts CaO, 35 parts Al2O3, 5 parts MgO, and 1 part metallic aluminum powder.

[0017] The preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder. Then, the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

[0018] The particle size of the mixed powder is 10 nm, the heating and melting temperature is 2860 °C, and the particle size of the composite calcium oxide slag is 0.1 mm.

[0019] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a four-stage heating method, and the impurities that float to the top of the melt are removed.

[0020] The preheating temperature in step (1) is 700℃, and the mass ratio of the composite calcium oxide slag to the alloy material is 0.2:100.

[0021] The four-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 800℃; the second stage is heating and holding, where the holding temperature is 900℃; the third stage is heating and holding, where the holding temperature is 1200℃; and the fourth stage is heating and holding, where the holding temperature is 1550℃.

[0022] The heating rate and holding time of the first stage are 10℃ / s and 3min, respectively, and the heating rate and holding time of the second stage are 30℃ / s and 1min, respectively.

[0023] The heating rate and holding time of the third stage are 30℃ / s and 10min, respectively, and the heating rate and holding time of the fourth stage are 10℃ / s and 8min, respectively.

[0024] Example 2 A composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 50 parts CaO, 38 parts Al2O3, 6.5 parts MgO, and 2 parts metallic aluminum powder.

[0025] The preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder. Then, the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

[0026] The particle size of the mixed powder is 15 nm, the heating and melting temperature is 2870 °C, and the particle size of the composite calcium oxide slag is 0.3 mm.

[0027] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a four-stage heating method, and the impurities that float to the top of the melt are removed.

[0028] The preheating temperature in step (1) is 750°C, and the mass ratio of the composite calcium oxide slag to the alloy material is 1:100.

[0029] The four-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 825℃; the second stage is heating and holding, where the holding temperature is 950℃; the third stage is heating and holding, where the holding temperature is 1350℃; and the fourth stage is heating and holding, where the holding temperature is 1565℃.

[0030] The heating rate and holding time in the first stage are 15℃ / s and 4min, respectively, and the heating rate and holding time in the second stage are 40℃ / s and 2min, respectively.

[0031] The heating rate and holding time of the third stage are 40℃ / s and 12min, respectively, and the heating rate and holding time of the fourth stage are 15℃ / s and 9min, respectively.

[0032] Example 3 A composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 52 parts CaO, 40 parts Al2O3, 8 parts MgO, and 3 parts metallic aluminum powder.

[0033] The preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder. Then, the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

[0034] The particle size of the mixed powder is 20 nm, the heating and melting temperature is 2880 °C, and the particle size of the composite calcium oxide slag is 0.5 mm.

[0035] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a four-stage heating method, and the impurities that float to the top of the melt are removed.

[0036] The preheating temperature in step (1) is 800℃, and the mass ratio of the composite calcium oxide slag to the alloy material is 2:100.

[0037] The four-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 850℃; the second stage is heating and holding, where the holding temperature is 1000℃; the third stage is heating and holding, where the holding temperature is 1500℃; and the fourth stage is heating and holding, where the holding temperature is 1580℃.

[0038] The heating rate and holding time of the first stage are 20℃ / s and 5min, respectively, and the heating rate and holding time of the second stage are 50℃ / s and 3min, respectively.

[0039] The heating rate and holding time of the third stage are 50℃ / s and 15min, respectively, and the heating rate and holding time of the fourth stage are 20℃ / s and 10min, respectively.

[0040] Comparative Example 1 Based on Example 2, a composite calcium oxide slag based on furnace lining adsorption is provided, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 50 parts CaO, 38 parts Al2O3, and 6.5 parts MgO.

[0041] The method for preparing the composite calcium oxide slag is as follows: aluminum oxide, calcium oxide, and magnesium oxide are placed in a heating furnace and heated and melted under a closed environment. After cooling, grinding, and sieving, the composite calcium oxide slag is obtained.

[0042] The heating and melting temperature is 2870℃, and the particle size of the composite calcium oxide slag is 0.3mm.

[0043] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a four-stage heating method, and the impurities that float to the top of the melt are removed.

[0044] The preheating temperature in step (1) is 750°C, and the mass ratio of the composite calcium oxide slag to the alloy material is 1:100.

[0045] The four-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 825℃; the second stage is heating and holding, where the holding temperature is 950℃; the third stage is heating and holding, where the holding temperature is 1350℃; and the fourth stage is heating and holding, where the holding temperature is 1565℃.

[0046] The heating rate and holding time in the first stage are 15℃ / s and 4min, respectively, and the heating rate and holding time in the second stage are 40℃ / s and 2min, respectively.

[0047] The heating rate and holding time of the third stage are 40℃ / s and 12min, respectively, and the heating rate and holding time of the fourth stage are 15℃ / s and 9min, respectively.

[0048] Comparative Example 2 Based on Example 2, a composite calcium oxide slag based on furnace lining adsorption is provided, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 50 parts CaO, 38 parts Al2O3, 6.5 parts MgO, and 2 parts metallic aluminum powder.

[0049] The preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder. Then, the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

[0050] The particle size of the mixed powder is 15 nm, the heating and melting temperature is 2870 °C, and the particle size of the composite calcium oxide slag is 0.3 mm.

[0051] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a three-stage heating method, and the impurities that float to the top of the melt are removed.

[0052] The preheating temperature in step (1) is 750°C, and the mass ratio of the composite calcium oxide slag to the alloy material is 1:100.

[0053] The three-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 825℃; the second stage is heating and holding, where the holding temperature is 950℃; and the third stage is heating and holding, where the holding temperature is 1565℃.

[0054] The heating rate and holding time in the first stage are 15℃ / s and 4min, respectively, and the heating rate and holding time in the second stage are 40℃ / s and 2min, respectively.

[0055] The heating rate and holding time for the third stage are 15℃ / s and 9min, respectively.

[0056] Comparative Example 3 Based on Example 2, a composite calcium oxide slag based on furnace lining adsorption is provided, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 50 parts CaO, 38 parts Al2O3, 6.5 parts MgO, and 2 parts metallic aluminum powder.

[0057] The preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder. Then, the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

[0058] The particle size of the mixed powder is 15 nm, the heating and melting temperature is 2870 °C, and the particle size of the composite calcium oxide slag is 0.3 mm.

[0059] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a two-stage heating method, and the impurities that float to the top of the melt are removed.

[0060] The preheating temperature in step (1) is 750°C, and the mass ratio of the composite calcium oxide slag to the alloy material is 1:100.

[0061] The two-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 825℃, and the second stage is heating and holding, where the holding temperature is 1565℃.

[0062] The heating rate and holding time in the first stage are 15℃ / s and 4min, respectively, and the heating rate and holding time in the second stage are 15℃ / s and 9min, respectively.

[0063] Comparative Example 4 Based on Example 2, a composite calcium oxide slag based on furnace lining adsorption is provided, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 50 parts CaO, 38 parts Al2O3, 6.5 parts MgO, and 2 parts metallic aluminum powder.

[0064] The preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder. Then, the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

[0065] The particle size of the mixed powder is 15 nm, the heating and melting temperature is 2870 °C, and the particle size of the composite calcium oxide slag is 0.3 mm.

[0066] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) Heat the furnace, keep it warm, and finally remove the impurities that float to the top of the melt.

[0067] The preheating temperature in step (1) is 750°C, and the mass ratio of the composite calcium oxide slag to the alloy material is 1:100.

[0068] The temperature for heat preservation in step (2) is 1565℃, and the heating rate and heat preservation time are 15℃ / s and 9min, respectively.

[0069] Comparative Example 5 Based on Example 2, a composite calcium oxide slag based on furnace lining adsorption is provided, wherein the composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 50 parts CaO, 38 parts Al2O3, 6.5 parts MgO, and 2 parts metallic aluminum powder.

[0070] The method for preparing the composite calcium oxide slag is as follows: aluminum powder, alumina, calcium oxide, and magnesium oxide are placed in a heating furnace and heated and melted under a closed environment. After cooling, grinding, and sieving, the composite calcium oxide slag is obtained.

[0071] The heating and melting temperature is 2870℃, and the particle size of the composite calcium oxide slag is 0.3mm.

[0072] An application of composite calcium oxide slag based on furnace lining adsorption, wherein the composite calcium oxide slag is used to purify alloy materials inside the furnace lining, and the specific method for using the composite calcium oxide slag to purify alloy materials inside the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a four-stage heating method, and the impurities that float to the top of the melt are removed.

[0073] The preheating temperature in step (1) is 750°C, and the mass ratio of the composite calcium oxide slag to the alloy material is 1:100.

[0074] The four-stage heating method in step (2) is as follows: the first stage is heating and holding, where the holding temperature is 825℃; the second stage is heating and holding, where the holding temperature is 950℃; the third stage is heating and holding, where the holding temperature is 1350℃; and the fourth stage is heating and holding, where the holding temperature is 1565℃.

[0075] The heating rate and holding time in the first stage are 15℃ / s and 4min, respectively, and the heating rate and holding time in the second stage are 40℃ / s and 2min, respectively.

[0076] The heating rate and holding time of the third stage are 40℃ / s and 12min, respectively, and the heating rate and holding time of the fourth stage are 15℃ / s and 9min, respectively.

[0077] Performance testing The composite calcium oxide slag prepared in Examples 1-3 and Comparative Examples 1-4 were used as samples. The ability of the samples to remove impurities from the alloy was tested in accordance with the test standard for adsorption performance of protective slag formulated by the Chinese National Standardization Administration (GB / T 24529). After the fourth stage of heating in the furnace lining was completed, the composite calcium oxide slag prepared in Examples 1-3 and Comparative Examples 1-4 was observed using SEM to examine the structure of the inner wall surface of the furnace lining and to calculate the film coverage rate. The specific formula for calculating the film coverage rate is: Film coverage rate % = Film area percentage / Total area inside the furnace lining × 100%. In addition, the lowest temperature of film formation was observed and recorded. The test results are shown in Table 1.

[0078] Table 1 Test Results Sample Impurity removal rate % Furnace lining inner wall surface structure Film coverage % Minimum film formation temperature (°C) Example 1 98.23 Smooth surface, no layering 98.65 955.3 Example 2 98.31 Smooth surface, no layering 98.87 955.0 Example 3 98.25 Smooth surface, no layering 98.85 955.1 Comparative Example 1 95.41 Rough surface, no layering 90.79 1352.0 Comparative Example 2 96.87 Rough surface, no layering 97.46 955.0 Comparative Example 3 96.29 Surface unevenness without layering 95.31 955.2 Comparative Example 4 95.97 Surface uneven layering 93.12 955.2 Comparative Example 5 97.89 Smooth surface, no layering 98.07 955.1 Analysis of the results in Table 1 shows that the inclusion removal rate of Examples 1-3 is greater than that of Comparative Examples 1-4, and the surfaces of Examples 1-3 are smooth and do not delaminate, with a film coverage rate of >98.5% and a minimum film formation temperature between 955-955.3℃. In Comparative Example 1, no aluminum powder was added, which failed to enhance the mechanical anchoring and chemical adsorption of the dynamic reaction film on the furnace lining surface. Consequently, the removal rate of inclusions and the film coverage decreased. At the same time, the pinning effect between the rough structures of magnesium aluminum spinel disappeared, and the increased spacing between the rough structures significantly reduced the film formation effect and raised the minimum film formation temperature to 400°C. Comparative Examples 2-4 used three-stage heating, two-stage heating, and one-stage heating methods, respectively. Due to the reduction of heating stages in the steps of Example 2, the melting of aluminum powder and its exothermic reaction with the magnesium aluminum spinel in the furnace lining were affected, resulting in discontinuous slag film with weak adhesion. This made the slag film easy to fall off during melt scouring, significantly reducing the purification effect. Ultimately, the furnace lining surface could not obtain a smooth surface structure. It can be seen that the fewer the heating stages, the worse the dynamic reaction film coverage and purification ability. In Comparative Example 5, the aluminum powder was not mixed and ground with alumina in advance. When the temperature was raised, the aluminum powder was exposed on the surface, making it easy to oxidize, which affected the film coverage and purification ability.

[0079] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A composite calcium oxide slag based on furnace lining adsorption, characterized in that, The composite calcium oxide slag based on furnace lining adsorption comprises the following raw materials in parts by weight: 48-52 parts CaO, 35-40 parts Al2O3, 5-8 parts MgO, and 1-3 parts metallic aluminum powder.

2. The composite calcium oxide slag based on furnace lining adsorption according to claim 1, characterized in that, The preparation method of the composite calcium oxide slag is as follows: first, aluminum powder and alumina are ball-milled in a high-energy ball mill to obtain a mixed powder. Then, the mixed powder, calcium oxide and magnesium oxide are put into a heating furnace and heated and melted under a closed environment. After cooling, grinding and sieving, the composite calcium oxide slag is obtained.

3. The composite calcium oxide slag based on furnace lining adsorption according to claim 2, characterized in that, The particle size of the mixed powder is 10-20 nm, the heating and melting temperature is 2860-2880 °C, and the particle size of the composite calcium oxide slag is 0.1-0.5 mm.

4. An application of the composite calcium oxide slag based on furnace lining adsorption as described in claim 1, characterized in that, The composite calcium oxide slag is used to purify alloy materials in the furnace lining. The specific method for using the composite calcium oxide slag to purify alloy materials in the furnace lining includes the following steps: (1) The inner wall of the magnesium-aluminum spinel furnace lining is preheated first, and then the composite calcium oxide slag is placed at the bottom of the furnace and alloy material is added; (2) The furnace adopts a four-stage heating method, and the impurities that float to the top of the melt are removed.

5. The application of composite calcium oxide slag based on furnace lining adsorption according to claim 4, characterized in that, The preheating temperature in step (1) is 700-800℃, and the mass ratio of the composite calcium oxide slag to the alloy material is 0.2-2:

100.

6. The application of the composite calcium oxide slag based on furnace lining adsorption according to claim 4, characterized in that, The four-stage heating method in step (2) is as follows: the first stage is heating and holding, with a holding temperature of 800-850℃; the second stage is heating and holding, with a holding temperature of 900-1000℃; the third stage is heating and holding, with a holding temperature of 1200-1500℃; and the fourth stage is heating and holding, with a holding temperature of 1550-1580℃.

7. The application of composite calcium oxide slag based on furnace lining adsorption according to claim 4, characterized in that, The heating rate and holding time in the first stage are 10-20℃ / s and 3-5min, respectively, and the heating rate and holding time in the second stage are 30-50℃ / s and 1-3min, respectively.

8. The application of the impact-resistant epoxy structural adhesive for repairing hinge joints according to claim 4, characterized in that, The heating rate and holding time of the third stage are 30-50℃ / s and 10-15min, respectively, and the heating rate and holding time of the fourth stage are 10-20℃ / s and 8-10min, respectively.