Method for improving quality of ironmaking molten steel of smelting furnace by using refractory material

Abstract

The invention relates to the technical field of metallurgical engineering, and discloses a method for improving the quality of iron-making molten steel in a smelting furnace by using a refractory material, which comprises the following steps: S1, selecting a basic refractory material with magnesium oxide as a main component, the magnesium oxide content accounts for more than 50% of the total amount of the refractory material, the melting point of the refractory material is in the range of 1000-1500 DEG C, and the refractory material is used as a raw material; a basic refractory material with magnesium oxide as a main component is adopted to react with acidic oxides in molten steel in a smelting furnace to generate magnesium sulfate (MgSO4) and magnesium phosphate (Mg3 (PO4) 2). In the process, harmful elements such as sulfur trioxide (SO3) and phosphorus pentoxide (P2O5) in the molten steel are effectively removed, so that the purity of the molten steel is improved. By removing the harmful impurities, the quality of molten steel can be remarkably improved, and hot brittleness and cold brittleness of the molten steel are reduced, so that the performance and the service life of final steel are improved.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical engineering, and in particular to a method for improving the quality of molten steel in a smelting furnace by utilizing refractory materials. Background Art

[0002] The method of using refractory materials to improve the quality of molten steel in smelting furnaces is mainly through the selection of high-purity, high-temperature stable refractory materials, optimizing the furnace lining structure and construction quality, and implementing antioxidant measures and maintenance monitoring. This method can reduce the reaction between slag and metal, reduce non-metallic inclusions in molten steel, and maintain a stable furnace environment, thereby improving the purity of molten steel and ironmaking efficiency. By scientifically managing the use of refractory materials, the life of the furnace lining can be effectively extended to ensure the smooth progress of the smelting process.

[0003] In practice, harmful impurities in molten steel are removed, among which the most harmful impurities in steel are S and P. One makes the steel hot and brittle, and the other makes the steel cold and brittle. When these two elements are oxidized under the action of oxygen, they form acidic oxides. The sulfur and phosphorus content in traditional molten steel cannot be effectively reduced, which makes the steel prone to hot and cold brittleness, affecting the mechanical properties and safety of the steel. In addition, no stable mineral phases such as magnesium sulfate, magnesium phosphate, calcium sulfate and calcium phosphate are formed, the slag is difficult to solidify, and it becomes difficult to separate impurities. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a method for improving the quality of molten steel in an ironmaking furnace by utilizing refractory materials, which solves the problem that the sulfur and phosphorus contents in traditional molten steel cannot be effectively reduced, resulting in the steel being susceptible to hot and cold brittleness, affecting the mechanical properties and safety of the steel, and failing to form stable mineral phases such as magnesium sulfate, magnesium phosphate, calcium sulfate and calcium phosphate, making it difficult for the slag to solidify and separating impurities.

[0005] To achieve the above objectives, the present invention is implemented by the following technical scheme: A method for improving the quality of molten steel in a smelting furnace by using refractory materials, comprising the following steps:

[0006] S1: Selecting a basic refractory material with magnesium oxide as the main component, wherein the magnesium oxide content accounts for more than 50% of the total amount of the refractory material, and the melting point of the refractory material is within the range of 1000-1500 degrees Celsius;

[0007] S2: Put the magnesium oxide refractory material into a smelting furnace to react with the acidic oxide in the molten steel to form the following compounds:

[0008] SO3+MgO→MgSO4

[0009] P2O5+3MgO→Mg3(PO4)2

[0010] S3: Calcium oxide is selected as a slag-forming agent, wherein the content of calcium oxide accounts for more than 60% of the total amount of the slag-forming agent, and the melting point of calcium oxide is within the range of 1400-1700 degrees Celsius:

[0011] S4: Add calcium oxide to the smelting furnace to ensure that it reacts with the acidic oxides in the molten steel to form the following compounds:

[0012] SO3+CaO→CaSO4

[0013] P2O5+3CaO→Ca3(PO4)2

[0014] S5: controlling the temperature in the furnace to be within the range of 1000 to 1500 degrees Celsius to ensure the above chemical reaction proceeds smoothly;

[0015] S6: Adjust the amount of magnesium oxide and calcium oxide added to optimize the chemical composition and formation rate of the slag;

[0016] S7: Cooling the slag and controlling the temperature during the cooling process to ensure that the mineral phase formed in the slag is solid and easy to remove from the molten steel;

[0017] S8: Adjust the dosage ratio of magnesium oxide to calcium oxide according to actual production conditions.

[0018] Preferably, the mass ratio of magnesium oxide in S2 is 1.2 to 2 times the actual required amount of acidic oxides in molten steel.

[0019] Preferably, the particle size of the calcium oxide in S3 is 1-5 mm to ensure its effective reaction in the furnace.

[0020] Preferably, the temperature in S5 is controlled within a range of 1200 to 1500 degrees Celsius.

[0021] Preferably, the S6 adjusts the amount of magnesium oxide and calcium oxide added by detecting the chemical composition of the slag in the furnace.

[0022] Preferably, in S7, the solidification process of the slag is controlled by adjusting the cooling rate to ensure the formation of a solid mineral phase.

[0023] Preferably, in S8, the dosage ratio of magnesium oxide to calcium oxide is the optimal ratio under actual production conditions.

[0024] Beneficial effects:

[0025] In the present invention, an alkaline refractory material with magnesium oxide as the main component is used to react with the acidic oxides in the molten steel in the smelting furnace to generate magnesium sulfate (MgSO4) and magnesium phosphate (Mg3(PO4)2). This process effectively removes harmful elements sulfur trioxide (SO3) and phosphorus pentoxide (P2O5) in the molten steel, thereby improving the purity of the molten steel. Removing these harmful impurities can significantly improve the quality of the molten steel, reduce the hot brittleness and cold brittleness of the molten steel, thereby improving the performance and service life of the final steel. Secondly, calcium oxide is selected as a slag-forming agent to react with the acidic oxides in the molten steel to generate calcium sulfate (CaSO4) and calcium phosphate (Ca3(PO4)2). This reaction not only neutralizes the acidic oxides in the molten steel, but also forms a stable solid mineral phase, making the treatment of slag more efficient. The use of calcium oxide reduces the slag-making cost, and its high melting point (1400-1700 degrees Celsius) ensures its stability at high temperatures, thereby improving the overall stability of the smelting process and the slag quality. In addition, the present invention The temperature control step (range of 1000 to 1500 degrees Celsius) in the invention ensures the smooth progress of the reaction. This temperature control not only optimizes the rate of the chemical reaction, but also reduces the damage to the furnace lining and equipment caused by excessive temperature, thereby extending the service life of the smelting equipment and reducing maintenance costs. By adjusting the amount and proportion of magnesium oxide and calcium oxide, the chemical composition and formation rate of the slag can be optimized according to actual production conditions. This flexible adjustment mechanism can achieve the best reaction effect under different production conditions, thereby ensuring the stability and consistency of the quality of the molten steel. Finally, the cooling process of the slag is controlled to ensure the solid formation of the mineral phase in the slag, which is convenient for removal from the molten steel, reducing the difficulties in the treatment process and improving production efficiency. This method not only improves the efficiency of the smelting process, but also optimizes each link of the production. In summary, the present invention achieves multiple optimizations in the smelting process by accurately controlling the use of refractory materials and slag-forming agents and their amount, significantly improving the quality of molten steel, and has the advantages of simple operation, stable effect, and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A flow chart of a method for improving the quality of molten steel in a smelting furnace by using refractory materials proposed by the present invention; DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] See also Figure 1, specifically including the following embodiments:

[0029] Example:

[0030] A method for improving the quality of molten steel in a smelting furnace by using refractory materials comprises the following steps:

[0031] S1: Select alkaline refractory materials with magnesium oxide as the main component, the magnesium oxide content accounts for more than 50% of the total amount of refractory materials, and the melting point of refractory materials is in the range of 1000-1500 degrees Celsius. When selecting refractory materials, alkaline refractory materials with magnesium oxide as the main component are preferred. Such refractory materials should ensure that the magnesium oxide content accounts for more than 50% of its total amount to ensure that it can effectively adsorb and neutralize acidic oxides in molten steel in the smelting furnace. The melting point of the selected refractory materials should be in the range of 1000-1500 degrees Celsius, so that it can maintain its stability under common smelting temperature conditions and avoid premature melting of the refractory materials due to too low melting point, thereby ensuring the effectiveness and durability of the refractory materials during the smelting process;

[0032] S2: Put the magnesium oxide refractory into the smelting furnace to react with the acidic oxides in the molten steel to form the following compounds:

[0033] SO3+MgO→MgSO4

[0034] P2O5+3MgO→Mg3(PO4)2, these chemical reactions can convert acidic oxides in molten steel (such as sulfur trioxide SO3 and phosphorus pentoxide P2O5) into stable solid compounds (magnesium sulfate and magnesium phosphate), thereby effectively removing harmful impurities in molten steel and improving the quality of molten steel;

[0035] S3: Calcium oxide is selected as the slag-forming agent. The content of calcium oxide accounts for more than 60% of the total amount of slag-forming agent. The melting point of calcium oxide is in the range of 1400-1700 degrees Celsius. Calcium oxide is selected as the slag-forming agent to ensure its effective reaction during the smelting process. The content of calcium oxide should account for more than 60% of the total amount of slag-forming agent to ensure its full participation in the reaction. The melting point of calcium oxide should be in the range of 1400-1700 degrees Celsius, so that it can maintain its stability and reactivity in a high-temperature smelting environment and prevent it from melting or failing prematurely at high temperatures:

[0036] S4: Add calcium oxide to the smelting furnace to ensure that it reacts with the acidic oxides in the molten steel to form the following compounds:

[0037] SO3+CaO→CaSO4

[0038] P2O5+3CaO→Ca3(PO4)2, these reactions convert acidic oxides in molten steel (such as sulfur trioxide and phosphorus pentoxide) into stable solid minerals (such as calcium sulfate and calcium phosphate), which helps to further remove harmful impurities in molten steel and improve the purity of molten steel;

[0039] S5: Control the temperature in the furnace within the range of 1000 to 1500 degrees Celsius to ensure the smooth progress of the above chemical reactions. During the smelting process, the temperature in the furnace must be accurately controlled and maintained within the range of 1000 to 1500 degrees Celsius. This temperature range can ensure the smooth reaction of magnesium oxide and calcium oxide with acidic oxides, avoiding damage to the furnace lining and equipment due to excessive temperature, and ensuring the efficiency and stability of the chemical reaction;

[0040] S6: Adjust the amount of magnesium oxide and calcium oxide added to optimize the chemical composition and formation rate of the slag. According to the actual content of acidic oxides in molten steel and smelting conditions, dynamically adjust the amount of magnesium oxide and calcium oxide added. This adjustment can optimize the chemical composition and formation rate of the slag, ensure the best chemical properties of the slag during the smelting process, and thus improve the quality of molten steel and smelting efficiency;

[0041] S7: Cool the slag and control the temperature during the cooling process to ensure that the mineral phase formed in the slag is solid and easy to remove from the molten steel. After the smelting is completed, the slag is cooled. By accurately controlling the temperature during the cooling process, the mineral phase formed in the slag is solid, which is easy to remove from the molten steel. This process helps to improve the slag treatment efficiency and reduce residual impurities in the molten steel;

[0042] S8: According to the actual production conditions, adjust the ratio of magnesium oxide to calcium oxide. According to the actual production conditions and the specific needs of molten steel, adjust the ratio of magnesium oxide to calcium oxide. This adjustment mechanism can achieve the best reaction effect in the smelting process and ensure the stability and consistency of molten steel quality;

[0043] The mass ratio of magnesium oxide in S2 is 1.2 to 2 times the actual demand for acidic oxides in molten steel. This ratio ensures an adequate supply of magnesium oxide and fully reacts with acidic oxides, thereby effectively removing harmful impurities.

[0044] The particle size of calcium oxide in S3 is 1-5 mm to ensure its effective reaction in the furnace. The appropriate particle size helps the calcium oxide to fully mix and react with the molten steel in the furnace, thereby improving its effect.

[0045] The temperature in S5 is controlled within the range of 1200 to 1500 degrees Celsius, which is an important control parameter to optimize reaction rate and stability, ensuring an efficient smelting process.

[0046] S6 adjusts the dosage of magnesium oxide and calcium oxide by detecting the chemical composition of the slag in the furnace. Real-time detection of the chemical composition of the slag can accurately adjust the dosage and optimize the reaction conditions and effects.

[0047] In S7, the solidification process of the slag is controlled by adjusting the cooling rate to ensure the formation of a solid mineral phase. Controlling the cooling rate can achieve stable solidification of the mineral phase in the slag, which is convenient for subsequent processing.

[0048] In S8, the feed ratio of magnesium oxide to calcium oxide is the optimal ratio under actual production conditions. The optimal ratio adjusted according to production conditions can effectively optimize various parameters in the smelting process and ensure high-quality production of molten steel.

[0049] The working principle of the present invention is to optimize the quality of molten steel in the smelting furnace by accurately controlling the use of refractory materials and slag-forming agents. The working principle of this process is described in detail below: First, alkaline refractory materials with magnesium oxide as the main component are used in the smelting process. Magnesium oxide has excellent ability to absorb acidic oxides in the smelting furnace. Its content accounts for more than 50% of the total amount of refractory materials, and its melting point is in the range of 1000 to 1200 degrees Celsius. Magnesium oxide refractory materials react chemically with acidic oxides (such as sulfur trioxide SO3 and phosphorus pentoxide P2O5) in molten steel in a high temperature environment. The specific reaction is:

[0050] SO3+MgO→MgSO4

[0051] P2O5+3MgO→Mg3(PO4)2

[0052] These reactions convert acidic oxides into stable solid compounds (magnesium sulfate and magnesium phosphate), and effectively remove harmful impurities in molten steel, thereby improving the purity of molten steel. Secondly, in the slag-making process, calcium oxide is selected as a slag-making agent, and its content accounts for more than 60% of the total slag-making agent. Its melting point is in the range of 1400 to 1700 degrees Celsius. Calcium oxide reacts with acidic oxides in molten steel to form a stable solid mineral phase. The specific reactions include:

[0053] SO3+CaO→CaSO4

[0054] P2O5+3CaO→Ca3(PO4)2

[0055] The use of calcium oxide effectively neutralizes the acidic oxides to form calcium sulfate and calcium phosphate. These products are stable and easy to handle, which helps to further purify the molten steel. Temperature control is an important part of the present invention. The temperature in the smelting furnace needs to be controlled in the range of 1000 to 1500 degrees Celsius to ensure the smooth progress of the chemical reaction. The appropriate temperature range ensures the reaction efficiency of magnesium oxide and calcium oxide with the acidic oxides, avoids the damage of the furnace lining and equipment to the excessively high temperature, and prolongs the service life of the equipment. During the operation, the amount and proportion of magnesium oxide and calcium oxide are precisely adjusted according to the actual acidic oxides in the molten steel. The content and production conditions are optimized. This flexible adjustment mechanism ensures the optimal chemical composition and reaction rate of the slag, thereby stabilizing the quality of the molten steel. Finally, the cooling process of the slag is also precisely controlled. By adjusting the cooling rate, it is ensured that the mineral phase in the slag forms a stable solid during the cooling process, which is convenient for removal from the molten steel. This process reduces the difficulty of processing and improves production efficiency. In general, the present invention optimizes each link in the smelting process by precisely controlling the selection, dosage and proportion of refractory materials and slag-forming agents, significantly improves the quality of molten steel and production efficiency, and ensures the performance and stability of steel.

[0056] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the application should be included in the protection scope of the present application.

Claims

1. A method for improving the quality of molten steel in a smelting furnace by using refractory materials, characterized in that: The following steps are involved: S1: Selecting a basic refractory material with magnesium oxide as the main component, wherein the magnesium oxide content accounts for more than 50% of the total amount of the refractory material, and the melting point of the refractory material is within the range of 1000-1500 degrees Celsius; S2: Put the magnesium oxide refractory material into a smelting furnace to react with the acidic oxide in the molten steel to form the following compounds: SO3+MgO→MgSO4 P2O5+3MgO→Mg3(PO4)2 S3: Calcium oxide is selected as a slag-forming agent, wherein the content of calcium oxide accounts for more than 60% of the total amount of the slag-forming agent, and the melting point of calcium oxide is within the range of 1400-1700 degrees Celsius: S4: Add calcium oxide to the smelting furnace to ensure that it reacts with the acidic oxides in the molten steel to form the following compounds: SO3+CaO→CaSO4 P2O5+3CaO→Ca3(PO4)2 S5: Control the temperature in the furnace within the range of 1000 to 1500 degrees Celsius to ensure the smooth progress of the chemical reaction; S6: Adjust the amount of magnesium oxide and calcium oxide added to optimize the chemical composition and formation rate of the slag; S7: Cooling the slag and controlling the temperature during the cooling process to ensure that the mineral phase formed in the slag is solid and easy to remove from the molten steel; S8: Adjust the dosage ratio of magnesium oxide to calcium oxide according to actual production conditions.

2. The method of improving the quality of molten steel in a smelting furnace by using refractory materials according to claim 1, characterized in that: The mass ratio of magnesium oxide in the S2 is 1.2 to 2 times the actual required amount of acidic oxides in the molten steel.

3. The method of improving the quality of molten steel in a smelting furnace by using refractory materials according to claim 1, characterized in that: The particle size of calcium oxide in S3 is 1-5 mm to ensure its effective reaction in the furnace.

4. The method of improving the quality of molten steel in a smelting furnace by using refractory materials according to claim 1, characterized in that: The temperature in S5 is controlled within a range of 1200 to 1500 degrees Celsius.

5. The method of improving the quality of molten steel in a smelting furnace by using refractory materials according to claim 1, characterized in that: The S6 adjusts the amount of magnesium oxide and calcium oxide added by detecting the chemical composition of the slag in the furnace.

6. The method of improving the quality of molten steel in a smelting furnace by using refractory materials according to claim 1, characterized in that: In S7, the solidification process of the slag is controlled by adjusting the cooling rate to ensure the formation of a solid mineral phase.

7. The method of improving the quality of molten steel in a smelting furnace by using refractory materials according to claim 1, characterized in that: In S8, the ratio of magnesium oxide to calcium oxide is the optimal ratio under actual production conditions.

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