A method for improving the slag depletion effect of ferrovanadium alloy and ferrovanadium alloy

Abstract

This invention relates to the field of alloy smelting technology, specifically to a method for improving the slag depletion effect of ferrovanadium alloy and a ferrovanadium alloy. The method includes: S1, preparing raw materials, the raw materials comprising a vanadium source and an iron source; S2, determining the value M based on the vanadium content in the vanadium source; S3, subtracting the mass of iron source M from the raw materials and then electro-aluminothermic smelting; S4, spraying the material after electro-smelting, followed by electro-refining; S5, after refining, cooling and dismantling the furnace to obtain an alloy cake, which is then water-quenched to obtain the ferrovanadium alloy. This invention, while considering slag refining, combines V-Fe-Mn or V-Fe-Si ternary phase diagram analysis to find suitable sedimentation methods and sedimentation agents for metallic vanadium in the slag, exhibiting good stability and strong operability.

Description

Technical Field

[0001] This invention relates to the field of alloy smelting technology, specifically to a method for improving the slag depletion effect of ferrovanadium alloys and ferrovanadium alloys. Background Technology

[0002] In the later stages of smelting ferrovanadium alloys, a reducing agent is usually injected into the molten ferrovanadium slag to achieve deep reduction, thereby reducing the residual vanadium element in the slag. The injection process uses inert gas as a carrier gas to transport the powder, and the stirring effect of the gas improves the reduction kinetics in the molten slag, which significantly reduces the vanadium content in the slag and increases the smelting yield.

[0003] In existing technologies, patent documents such as "A method for spray refining ferrovanadium alloy (application number: CN201610807028.5)" and "A method for using vanadium-aluminum alloy fine powder for ferrovanadium spray refining (application number: CN201910814552.9)" both improve the physicochemical properties of ferrovanadium slag by improving the composition of the sprayed material. However, the sprayed materials used are ferrovanadium powder and vanadium-aluminum powder, respectively, both of which have relatively high melting points, easily causing large fluctuations in the main element composition of the alloy and hindering the smooth settling of the alloy. Microscopic analysis of ferrovanadium smelting slag often reveals a certain amount of high-vanadium alloy that has not yet settled into the alloy liquid in the lower part of the corundum slag; moreover, the preparation process of ferrovanadium and vanadium-aluminum powders is energy-intensive, which is not conducive to the actual raw material preparation operation.

[0004] Therefore, there is an urgent need to develop a method that is highly operable and can stably improve the refining and depletion effect of slag. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the slag leaning effect in the ferrovanadium injection refining step of the prior art is unstable, and the injection material is prone to clogging during the injection process. The present invention provides a method that is highly operable and can stably improve the effect of slag refining, which can avoid the clogging of injection material in the ferrovanadium refining step, and at the same time increase the vanadium content in the slag in the refining step and improve the smelting yield.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0007] The first aspect of this invention provides a method for improving the depletion effect of ferrovanadium alloy slag, the method comprising the following steps:

[0008] S1. Prepare the ingredients, which include a vanadium source and an iron source;

[0009] S2. Determine the value of M based on the vanadium content in the vanadium source;

[0010] S3. After subtracting the iron source of mass M from the ingredients, the iron source is smelted by electrothermal smelting.

[0011] S4. After the electro-smelting process is completed, the material is sprayed and then electro-refined.

[0012] S5. Refining is completed, the furnace is cooled and dismantled to obtain an alloy cake. The alloy cake is then water-quenched to obtain ferrovanadium alloy.

[0013] The material being sprayed includes aluminum powder and additive 1;

[0014] The additive 1 includes alloy powder and an iron source;

[0015] The alloy powder includes manganese or silicon.

[0016] In general, the vanadium and iron sources are set according to the FeV80 grade requirements for the vanadium-iron ratio.

[0017] Furthermore, the vanadium-iron alloy is FeV80.

[0018] Furthermore, after the electro-refining of S4, slag is obtained, and the value of M is the total vanadium mass in the slag of S4.

[0019] Furthermore, the value of M is 1 to 5% of the total mass of the slag in S4, including but not limited to 1%, 2%, 3%, 4% or 5%.

[0020] In this invention, the total vanadium mass in the slag in step S4 is generally 1-5% of the total slag mass. Further, the step S4 includes first spraying aluminum powder, then refining it by electric current for t'min, followed by spraying auxiliary agent 1.

[0021] The t'min is 5 to 30 min, preferably 8 to 12 min, and more preferably 5 min.

[0022] Furthermore, the additive 1 contains manganese or silicon, wherein the mass of manganese is N, and / or the mass of silicon is N', wherein N is calculated based on the national standard GB / T4139-2012 requiring an upper limit of 1.5% manganese, a manganese yield of 100%, and the mass of the alloy cake, and wherein N' is calculated based on the national standard GB / T4139-2012 requiring an upper limit of 0.5% silicon, a silicon yield of 100%, and the mass of the alloy cake.

[0023] Furthermore, the additive 1 comprises at least two of the following: ferrosilicon alloy, metallic silicon, and metallic iron; or, the additive 1 comprises at least two of the following: ferromanganese alloy, metallic manganese, and metallic iron.

[0024] Preferably, the additive 1 is selected from a mixture of ferromanganese alloy and metallic manganese or a mixture of ferrosilicon alloy and metallic silicon.

[0025] The additive 1 is in powder form, which makes the material in the gun barrel in a suspended (dispersed) flow dilute phase conveying state during spraying, reducing the phenomenon of concentrated powder spraying and uneven airflow caused by excessive instantaneous conveying volume.

[0026] Furthermore, the refining time in S4 is 10 to 30 minutes.

[0027] Furthermore, the blowing is performed using a spray gun. Determining the spray gun depth range includes: determining the slag temperature in the refining step, and simultaneously adjusting the spray gun depth range h to satisfy: 0.3×(h1+h2)≤h≤0.7×(h1+h2), where h1 is the height of the curved section of the spray gun head, and h2 is the theoretical maximum critical depth of the spray gun; the formula for calculating h2 is... Where π is 3.14, c is the specific heat capacity of the injected non-oxidizing gas in J / (kg·℃), m is the feed rate of aluminum powder during injection in kg / s, t0 is the initial temperature of injection (i.e., the inlet temperature of the injected material), t is the final temperature of injection (the melting point of aluminum), and t w1 The inner wall temperature is the slag temperature during the refining process; t w 2 is the outer wall temperature, which is the melting point of aluminum; П is the heat transfer coefficient of the casting layer of the spray gun wall material; d1 is the inner diameter of the spray gun barrel wall; d2 is the outer diameter of the spray gun barrel wall; the spray gun will not experience material blockage within the above depth range.

[0028] In one embodiment of the present invention, the t0 is generally equal to room temperature, specifically 22 to 28°C.

[0029] In one embodiment of the present invention, t is the melting point of aluminum, which is 660°C.

[0030] In one embodiment of the present invention, П is the heat transfer coefficient of cement, specifically 0.08 W·m. -1 ·℃ -1 .

[0031] Furthermore, the method for determining the slag temperature in the refining step is as follows: the slag system composition of the slag in the refining step is mapped to a ternary phase diagram to determine the slag temperature.

[0032] In one embodiment of the present invention, the temperature of the molten slag is 1900°C.

[0033] Furthermore, the length of h1 is selected from 50 to 100 mm.

[0034] Furthermore, the injected gas is a non-oxidizing gas, including but not limited to: nitrogen, argon, helium or carbon dioxide.

[0035] Furthermore, the non-oxidizing gas is nitrogen.

[0036] Furthermore, the method also includes cooling and dismantling the furnace, and water quenching the alloy cake to obtain ferrovanadium alloy with the required product quality.

[0037] A second aspect of the present invention provides a vanadium-iron alloy prepared by the method described in the first aspect.

[0038] By adopting the above technical solution, the present invention has at least the following beneficial effects:

[0039] (1) This invention combines ternary phase diagram analysis to find suitable sedimentation methods and sedimentation agents for metallic vanadium in slag. Under the premise of ensuring the iron balance of the system materials, the "iron reduction smelting-alloying depletion" technical concept is established. A certain amount of iron source is reduced in the conventional batching, and a corresponding amount of iron source is added in the refining step. While avoiding fluctuations in the content of the main alloying elements, the iron source and sedimentation agent added in the iron supplementation refining step can jointly create an environment conducive to slag depletion. This can help the high melting point primary metallic vanadium in the slag to successfully complete the alloying process, maintain the liquid state for a long time, and have the function of inducing sedimentation. It promotes droplet spheroidization, increases the probability of Brownian motion collision, Stokes collision, and turbulent collision, and ensures that the vanadium alloy can successfully polymerize and settle in the slag, thus fully exerting the effect of reducing the residual vanadium content in the slag.

[0040] (2) The present invention uses a suitable and reliable depth model for ferrovanadium spray guns to determine the appropriate depth of the nozzle in the spraying step, and guides the improvement of the spraying blockage phenomenon in the ferrovanadium spraying refining step. It can prevent the problem of poor depletion effect caused by improper depth parameter settings during the use of the spray gun.

[0041] (3) The fine grinding performance of the vanadium-iron alloy prepared by the method of the present invention for improving the slag depletion effect of vanadium-iron alloy is significantly increased compared with the prior art. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 The diagram shown is a V-Fe-Si ternary phase diagram used in Examples 1 and 2.

[0044] Figure 2 The figure shown is the V-Fe-Mn ternary phase diagram referenced in Example 3;

[0045] Figure 3The diagram shown is a CaO-Al2O3-MgO ternary phase diagram for reference in Examples 1, 2 and 3. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to specific examples and the accompanying drawings.

[0047] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0048] Unless otherwise defined, all scientific and technical terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art.

[0049] Unless otherwise defined, all percentages in this invention are mass percentages.

[0050] In this invention, "corundum slag" refers to the alloy cake formed after the vanadium-iron alloy refining step is completed and the slag is cooled. The interior of the cake undergoes conventional treatments such as water quenching to form a vanadium-iron alloy, while the exterior is covered with a layer of slag-like material (i.e., the slag-like material attached to the alloy in step S5). The corundum slag contains Al2O3 and vanadium-iron that did not settle during the refining process. In this invention, this slag-like material is called "corundum slag." The sphericity of the metallic alloy in corundum slag reflects the depletion effect of ferrovanadium alloy slag. Specifically, after refining, most of the ferrovanadium alloy settles into an alloy cake. The alloy cake is then water-quenched to obtain ferrovanadium alloy. A layer of corundum slag surrounds the alloy cake, containing ferrovanadium alloy that did not settle during refining. These ferrovanadium alloys are dispersed in the corundum slag and, upon cooling, yield small solid ferrovanadium alloy particles. When the content of non-settled ferrovanadium alloy in the corundum slag is high, the small solid ferrovanadium alloy particles are irregularly shaped. Conversely, when the content of non-settled ferrovanadium alloy in the corundum slag is low, the small solid ferrovanadium alloy particles are spherical. The higher the sphericity of the small solid ferrovanadium alloy particles, the lower the content of non-settled ferrovanadium alloy in the corundum slag, thus indirectly characterizing the depletion effect of the ferrovanadium alloy slag. In other words, the higher the sphericity value of the metallic alloy in corundum slag, the lower the content of non-settled ferrovanadium alloy in the corundum slag, indicating a better depletion effect of the ferrovanadium alloy slag.

[0051] The beneficial effects of the present invention will be further illustrated below with reference to specific embodiments.

[0052] Example 1:

[0053] In the FeV80 smelting process, the total amount of iron added is determined according to the iron-vanadium ratio of the alloy grade. Based on the residual vanadium content and slag mass, the total vanadium weight in the slag is calculated to be 40 kg (determined based on the vanadium content in the vanadium source). Vanadium is fully recovered from the slag according to a V:Fe = 1:1 (mass ratio). Therefore, 40 kg of metallic iron is subtracted during the smelting period (in this example, the slag weight is approximately 2 t, and the residual vanadium content in the slag is 2%, thus determining the metallic iron content), for use in the refining step. Based on the silicon balance in the ferrovanadium alloy, the alloy cake mass, and the national standard upper limit for silicon content, and based on the total weight of the alloy cake and the silicon content required by national standard GB / T4139-2012, 20 kg of silicon can be added to the ferrovanadium alloy refining step. Then, smelting is carried out according to conventional operations. Afterwards, refining is performed. In the ferrovanadium slag refining step, the slag composition is mapped to the CaO-MgO-Al2O3 phase diagram, as shown below. Figure 3 As shown, the slag temperature is determined to be approximately 1900℃. c----specific heat capacity, using the specific heat capacity of nitrogen, which is 1.038 J / (kg·℃) from the table; m----aluminum powder velocity, kg / s; t0----initial temperature during injection, Al powder inlet temperature 25℃; t----final temperature during injection, 660℃ (melting point of Al). The mass of aluminum powder injected per unit time, m, is 0.28 kg / s. t w1 t w2 The inner and outer walls maintain uniform and stable temperatures of 1900℃ and 660℃ respectively; h2 is the maximum critical depth of the spray gun in the molten slag when the aluminum powder just melts in the spray gun, calculated theoretically; the gun wall material is self-flowing castable, π is the heat transfer coefficient of the casting layer, which is the heat transfer coefficient of cement, i.e., 0.08w·m⁻¹·℃⁻¹; d1, d2 are the inner and outer diameters of the spray gun cylinder wall, with an outer diameter of 200mm and an inner diameter of 20mm; h1 is the length of the spray gun elbow end, 0.08m. (π is taken as 3.14 for calculation) Substituting the data into the above formula, the critical depth of the spray gun in the slag layer when the aluminum powder just reaches its melting point in the spray gun at different spraying rates was calculated (see Table 1). That is, when the aluminum powder speed is 0.28 kg / s, the spray gun depth should be less than 0.67 m to avoid the aluminum powder melting in the gun barrel. Based on this, according to the formula: 0.3×(h1+h2)≤h≤0.7×(h1+h2), the actual safe depth range h of the spray gun is obtained as 0.225 m~0.525 m. On this basis, the aluminum powder spraying amount is calculated by multiplying the difference between the upper limit of the aluminum content of Grade A alloy in the national standard and the current aluminum content with the alloy cake (in this embodiment, the difference between the upper limit of the aluminum content of Grade A alloy cake and the current average aluminum content is 0.5%, and the raw material brings in an alloy cake mass of 10t). 50 kg of aluminum powder is sprayed, and then the electrode is lowered and energized for 10 min; the spraying additive 1 is sprayed according to Figure 1The composition of additive 1 was determined by the liquidus line. Additive 1 is a mixture of ferrosilicon alloy powder and metallic silicon powder. The total iron content in additive 1 is 40 kg and the total silicon content is 20 kg. The electrode heats the molten slag and holds it at that temperature for 30 min. Following standard procedures, the process of cooling and dismantling the furnace, water quenching the alloy cake, sampling and testing, weighing, and statistical analysis were completed.

[0054] Table 1 Critical depth of the spray gun in the slag at different spraying velocities / mm

[0055]

[0056] Example 2

[0057] The total amount of iron added is determined based on the iron-vanadium ratio of the alloy grade. Combining the residual vanadium content in the slag and the slag mass, the total vanadium weight in the slag is calculated to be 60 kg (based on the vanadium content in the vanadium source). Vanadium is fully recovered from the slag according to a V:Fe ratio of 1:1 (mass ratio). Therefore, 60 kg of metallic iron is subtracted during the smelting period (in this example, the slag weight is approximately 2 t, and the residual vanadium content in the slag is 3%), for use in the refining step. Based on the silicon balance in the ferrovanadium alloy, the alloy cake mass, and the national standard's upper limit for silicon content, and based on the total weight of the alloy cake and the silicon content required by national standard GB / T4139-2012, the mass of silicon that can be added in the ferrovanadium alloy refining step is calculated to be 22 kg. Smelting is then carried out according to conventional operations, followed by refining. In the ferrovanadium slag refining step, the slag composition is mapped to the CaO-MgO-Al2O3 phase diagram, as shown below. Figure 3 As shown, the slag temperature is determined to be approximately 1900℃. c----specific heat capacity, using the specific heat capacity of nitrogen, which is 1.038 J / (kg·℃) from the table; m----aluminum powder velocity, kg / s; t0----initial temperature during injection, Al powder inlet temperature 25℃; t----final temperature during injection, 660℃ (melting point of Al). The mass of aluminum powder injected per unit time, m, is 0.28 kg / s. t w1 t w2 The inner and outer walls maintain uniform and stable temperatures of 1900℃ and 660℃ respectively; h2 is the maximum critical depth of the spray gun in the molten slag when the aluminum powder just melts in the spray gun, calculated theoretically; the gun wall material is self-flowing castable refractory, π is the heat transfer coefficient of the casting layer, which is the heat transfer coefficient of cement, i.e., 0.08 W·m⁻¹·℃⁻¹; d1, d2 are the inner and outer diameters of the spray gun cylinder wall, with an outer diameter of 200 mm and an inner diameter of 20 mm; h1 is the length of the elbow end of the spray gun, 0.01 m. (π is taken as 3.14 for calculation) Substituting the data into the above formula, the critical depth of the spray gun in the slag layer when the aluminum powder just reaches the melting point in the spray gun at different spraying rates was calculated (see Table 1). That is, when the aluminum powder speed is 0.28 kg / s, the spray gun depth should be less than 0.67 m to avoid the aluminum powder melting in the gun barrel. Based on this, according to the formula: 0.3×(h1+h2)≤h≤0.7×(h1+h2), the actual safe depth range h of the spray gun is obtained as 0.204 m~0.476 m. On this basis, the aluminum powder spraying amount is calculated by multiplying the difference between the upper limit of the aluminum content of Grade A alloy in the national standard and the current aluminum content with the alloy cake (in this embodiment, the difference between the upper limit of the aluminum content of Grade A alloy cake and the current average aluminum content is 0.2%, and the raw material brings in an alloy cake mass of 10 t). 20 kg of aluminum powder is sprayed, and then the electrode is lowered and energized for 12 min; the additive 1 is sprayed according to Figure 1 The composition of additive 1 was determined. Additive 1 is a mixture of metallic iron powder and metallic silicon powder. The total iron content in additive 1 is 60 kg and the total silicon content is 22 kg. The electrode was heated to heat the slag and kept at that temperature for 30 min. The process of cooling and dismantling the furnace, water quenching and sampling of the alloy cake, weighing, and statistical analysis were completed according to the routine operation.

[0058] Example 3

[0059] The total amount of iron added is determined based on the iron-vanadium ratio of the alloy grade. Combining the residual vanadium content in the slag and the slag mass, the total vanadium weight in the slag is calculated to be 100 kg. Following a V:Fe = 1:1 (mass ratio), sufficient vanadium is recovered from the slag. Therefore, 100 kg of metallic iron is subtracted during the smelting period (in this example, the slag weight is approximately 2 tons, and metallic iron is 5% of the total slag weight) for use during the refining steps. Based on the manganese balance in the ferrovanadium alloy, the alloy cake mass, and the national standard upper limit for manganese content, and based on the total weight of the alloy cake and the manganese content required by national standard GB / T4139-2012, 18 kg of manganese can be added during the ferrovanadium alloy refining step. Smelting is then carried out according to conventional operations. Refining is then performed. In the ferrovanadium slag refining step, the slag composition is mapped to the CaO-MgO-Al2O3 phase diagram, as shown below. Figure 3 As shown, the slag temperature is determined to be approximately 1900℃. c----specific heat capacity, using the specific heat capacity of nitrogen, which is 1.038 J / (kg·℃) from the table; m----aluminum powder velocity, kg / s; t0----initial temperature during injection, Al powder inlet temperature 25℃; t----final temperature during injection, 660℃ (melting point of Al). The mass of aluminum powder injected per unit time, m, is 0.28 kg / s. t w1 t w2The inner and outer walls maintain uniform and stable temperatures of 1900℃ and 660℃ respectively; h2 is the maximum critical depth of the spray gun in the molten slag when the aluminum powder just melts in the spray gun, calculated theoretically; the gun wall material is self-flowing castable refractory, π is the heat transfer coefficient of the casting layer, which is the heat transfer coefficient of cement, i.e., 0.08w·m⁻¹·℃⁻¹; d1, d2 are the inner and outer diameters of the spray gun cylinder wall, with an outer diameter of 200mm and an inner diameter of 20mm; h1 is the length of the spray gun elbow end, 0.10m. (π is taken as 3.14 for calculation) Substituting the data into the above formula, the critical depth of the spray gun in the slag layer when the aluminum powder just reaches its melting point in the spray gun at different spraying rates was calculated (see Table 1). That is, when the aluminum powder speed is 0.28 kg / s, the spray gun depth should be less than 0.67 m to avoid the aluminum powder melting in the gun barrel. Based on this, according to the formula: 0.3×(h1+h2)≤h≤0.7×(h1+h2), the actual safe depth range h of the spray gun is obtained as 0.231 m~0.539 m. On this basis, the aluminum powder spraying amount is calculated by multiplying the difference between the upper limit of the aluminum content of Grade A alloy in the national standard and the current aluminum content with the alloy cake (in this embodiment, the difference between the upper limit of the aluminum content of Grade A alloy cake and the current average aluminum content is 0.15%, and the raw material brings in an alloy cake mass of 10 t). 15 kg of aluminum powder is sprayed, and then the electrode is lowered and energized for 11 min; the additive 1 is sprayed according to Figure 2 The composition of additive 1 is determined. Additive 1 is a mixture of iron powder and manganese powder. The total iron content of additive 1 is 100 kg and the total manganese content is 18 kg. The electrode heats the molten slag and holds it at that temperature for 30 min. The process of cooling and dismantling the furnace, water quenching the alloy cake, sampling and testing, weighing, and statistical analysis are completed according to conventional operation.

[0060] Comparative Example 1

[0061] Referring to the parameters and steps of Example 3, the only difference is that, compared with Example 3, no metallic iron is removed during the smelting period, no metallic iron is added during the refining step, and 50 kg of aluminum powder is sprayed in the refining step and then the electrode is energized for 30 minutes; the cooling furnace dismantling, alloy cake water quenching, sampling and testing, weighing, statistical analysis and other processes are completed according to conventional operation.

[0062] Experimental Example 1:

[0063] Comparison method: The vanadium alloy smelting yields of Examples 1-3 and Comparative Example 1 were statistically analyzed; the Mn or Si content in the alloy was detected, and the smelting time per ton of vanadium-iron alloy was statistically analyzed. The sphericity of the metallic alloy in the resulting corundum slag was also detected to characterize the slag depletion effect of the vanadium-iron alloy slag. The comparison results are shown in Table 2. The results show that the embodiments of the present invention significantly improve upon traditional indicators. The average smelting time per ton of vanadium-iron alloy was shortened by 8.39 min, the sphericity of residual metallic vanadium in the corundum slag was significantly improved, and the average smelting yield increased by 1.06 percentage points, thus enhancing the slag depletion effect.

[0064] Table 2 Smelting Details

[0065]

[0066] It should be noted that the components or steps in the above embodiments can be interchanged, substituted, added, or deleted. Therefore, the combinations formed by these reasonable permutations and transformations should also fall within the protection scope of this invention, and the protection scope of this invention should not be limited to the above embodiments.

[0067] The above are exemplary embodiments disclosed in this invention. The order of the disclosed embodiments is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. However, it should be noted that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the disclosed embodiments of this invention (including the claims) is limited to these examples. Various changes and modifications can be made without departing from the scope defined by the claims. The functions, steps, and / or actions of the methods according to the disclosed embodiments described herein do not need to be performed in any particular order. Furthermore, although the elements disclosed in the embodiments of this invention may be described or claimed individually, they may be understood as multiple unless explicitly limited to a singular.

[0068] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples. Within the framework of the invention, technical features of the above embodiments or different embodiments can be combined, and many other variations of the different aspects of the invention as described above exist, which are not provided in the details for the sake of brevity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the protection scope of the invention.

Claims

1. A method for improving the slag depletion effect of ferrovanadium alloy slag, characterized in that, The method includes the following steps: S1. Prepare the ingredients, which include a vanadium source and an iron source; S2. Determine the value of M based on the vanadium content in the vanadium source; S3. After subtracting the iron source of mass M from the ingredients, the iron source is smelted by electrothermal smelting. S4. After the electro-smelting process is completed, the material is sprayed and then electro-refined. S5. Refining is completed, the furnace is cooled and dismantled to obtain an alloy cake. The alloy cake is then water-quenched to obtain ferrovanadium alloy. The material being sprayed includes aluminum powder and additive 1; The additive 1 includes an alloy powder and an iron source, and the additive 1 contains at least two of the following: ferrosilicon alloy, metallic silicon, and metallic iron; or, the additive 1 contains at least two of the following: ferromanganese alloy, metallic manganese, and metallic iron. The alloy powder includes manganese or silicon. After electrorefining S4, slag is obtained. The value of M is the total vanadium mass in the S4 slag, and the value of M is 1~5% of the total mass of the slag in S4. The S4 blowing step includes first blowing aluminum powder, refining it by electricity for t'min, and then blowing additive 1, wherein t'min is 5~30 min; The blowing process is performed using a spray gun. Determining the spray gun depth range includes: determining the slag temperature in the refining step, and simultaneously adjusting the spray gun depth range h to satisfy: 0.3 × (h1 + h2) ≤ h ≤ 0.7 × (h1 + h2), where h1 is the height of the curved section of the spray gun head, and h2 is the theoretical maximum critical depth of the spray gun; the formula for calculating h2 is... Where π is 3.14, c is the specific heat capacity of the non-oxidizing gas being injected, in J / (kg·℃), m is the material velocity of aluminum powder in the injected material, in kg / s, t0 is the initial temperature of the injection, i.e., the inlet temperature of the injected material, t is the final temperature of the injection, which is the melting point of aluminum, tw1 is the inner wall temperature, i.e., the slag temperature in the refining step; tw2 is the outer wall temperature, which is the melting point of aluminum; П is the heat transfer coefficient of the casting layer of the spray gun wall material, d1 is the inner diameter of the spray gun barrel wall, and d2 is the outer diameter of the spray gun barrel wall.

2. The method as described in claim 1, characterized in that, The vanadium-iron alloy is FeV80.

3. The method as described in claim 1, characterized in that, The method for determining the slag temperature in the refining step is as follows: the slag system composition of the slag in the refining step is mapped to a ternary phase diagram to determine the slag temperature.

4. The method as described in claim 1, characterized in that, The length of h1 is selected from 50~100mm.

5. The method as described in claim 1, characterized in that, The injected gas is a non-oxidizing gas, including nitrogen, argon, helium, or carbon dioxide.

6. A vanadium-iron alloy prepared by the method according to any one of claims 1 to 5.

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