Method for smelting nickel-containing steel grades using diamond wire

Abstract

The application provides a method for smelting nickel-containing steel by using diamond wire, which comprises the following steps: adding the diamond wire, scrap steel and molten iron into a converter for oxygen blowing smelting to obtain converter steel liquid; transferring the converter steel liquid into a ladle for deoxidation treatment to obtain deoxidized steel liquid; transferring the deoxidized steel liquid into a refining furnace for desulfurization and deoxidation to obtain refined steel liquid; performing nickel adjustment treatment on the refined steel liquid to obtain nickel-containing steel liquid; and performing continuous casting treatment on the nickel-containing steel liquid to obtain nickel-containing steel billets. The absolute value of the difference between the actual nickel content in the nickel-containing steel liquid and the target nickel content of the nickel-containing steel liquid is not greater than 0.005%. In the method, the diamond wire is added into the converter together with the scrap steel and the molten iron, and the diamond wire is melted through oxygen blowing smelting, so that the nickel yield is ensured, the amount of nickel-iron alloy is greatly reduced under the condition that the nickel content in the prepared nickel-containing steel reaches the preset target value, the cost is reduced, and the production benefit can be effectively improved.

Description

Technical Field

[0001] This application relates to the field of iron and steel metallurgy technology, and in particular to a method for smelting nickel-containing steel using diamond wire. Background Technology

[0002] Nickel is a commonly used alloying element that can improve the strength of steel without reducing its plasticity, improve the low-temperature toughness of steel, reduce the critical cooling rate of steel, improve the hardenability of steel, expand the austenite region, and is an effective element for austenitization. It also has a certain degree of corrosion resistance and good resistance to some reducing acids.

[0003] Diamond wire, used as a linear cutting tool for cutting superhard materials such as marble and silicon wafers, utilizes a uniform nickel coating on the steel wire to provide adhesion and electrical conductivity for the diamond. After production, the diamond wire contains over 20% Ni, and recycling and remelting it requires significant electrical resources. Steel plants directly alloy the finished diamond wire, reducing both the cost of nickel alloying and electrical energy consumption, thus contributing to energy conservation and carbon reduction. Summary of the Invention

[0004] This application provides a method for smelting nickel-containing steel using diamond wire, which can achieve a preset target value for the nickel content in the prepared nickel-containing steel and reduce the cost of nickel alloying.

[0005] This application provides a method for smelting nickel-containing steel using diamond wire, comprising the following steps: adding diamond wire, scrap steel, and molten iron to a converter for oxygen blowing smelting to obtain converter molten steel; transferring the converter molten steel to a ladle for deoxidation treatment to obtain deoxidized molten steel; transferring the deoxidized molten steel to a refining furnace for desulfurization and deoxidation to obtain refined molten steel; subjecting the refined molten steel to nickel adjustment treatment to obtain nickel-containing molten steel; and continuously casting the nickel-containing molten steel to obtain nickel-containing steel billets; wherein the absolute value of the difference between the actual nickel content and the target nickel content in the nickel-containing molten steel is not greater than 0.005%.

[0006] According to an embodiment of this application, the step of adding diamond wire, scrap steel and molten iron to a converter for oxygen blowing smelting to obtain converter molten steel includes: determining the amount of diamond wire added, m1, based on the mass of the converter molten steel, m2, the nickel content of the diamond wire, c1, the weight of the molten iron, m3, the nickel content of the molten iron, c2, the weight of the scrap steel, m4, and the nickel content of the scrap steel, c3.

[0007] According to an embodiment of this application, the amount of diamond wire added satisfies the following relationship: m2×c5=(m1×c1+m3×c2+m4×c3)×b;

[0008] Where m1 represents the amount of diamond wire input; m2 represents the weight of molten steel in the converter; m3 represents the weight of molten iron; m4 represents the weight of scrap steel; c1 represents the nickel content of the diamond wire, not less than 20%; c2 represents the nickel content of the molten iron; c3 represents the nickel content of the scrap steel; c4 represents the target nickel content of the nickel-containing molten steel; c5 represents 85%-95% of c4; b represents the nickel recovery rate, which is not less than 94%.

[0009] According to an embodiment of this application, the step of transferring molten steel from a converter to a ladle for deoxidation treatment to obtain deoxidized molten steel includes: continuously blowing argon gas at the bottom of the ladle for stirring, with an argon gas flow rate of 250-350 NL / min.

[0010] According to an embodiment of this application, in the step of adding diamond wire, scrap steel and molten iron to a converter for oxygen blowing smelting to obtain converter steel, the diamond wire is a pre-treated short cut segment with a single segment length of 30-50cm.

[0011] According to an embodiment of this application, the step of transferring molten steel from a converter to a ladle for deoxidation treatment to obtain deoxidized molten steel includes: adding a deoxidizing agent to the molten steel from the converter for deoxidation treatment.

[0012] According to the embodiments of this application, the amount of deoxidizer added is 0.1-0.6 wt% of the converter molten steel;

[0013] According to embodiments of this application, the deoxidizer includes one or more of manganese alloys, silicon alloys, and aluminum alloys.

[0014] According to the embodiments of this application, the deoxidizer is added in batches, with each addition not exceeding 30% of the total addition, and each addition is spaced 1-2 minutes apart.

[0015] According to an embodiment of this application, after the temperature inside the refining furnace reaches the target temperature, desulfurization and deoxidation treatment is performed; the target temperature is 1600-1650℃.

[0016] According to embodiments of this application, the desulfurization and deoxidation treatment includes adding aluminum blocks for deoxidation and adding lime for desulfurization.

[0017] According to an embodiment of this application, the amount of aluminum block added is 0.1-0.4 wt% of the mass of the deoxidized molten steel.

[0018] According to the embodiments of this application, the amount of lime added is 0.3-0.6 wt% of the mass of the deoxidized molten steel.

[0019] According to an embodiment of this application, the step of subjecting refined molten steel to nickel-containing molten steel through nickel adjustment includes:

[0020] Temperature sampling was performed on the refined molten steel to determine its nickel content, which was marked as d. The total mass of the refined molten steel was marked as m5. The nickel content in the refined molten steel was compared with the target value of nickel content in nickel-containing steel. Based on the comparison results, a regulating alloy with a mass of m6 was added to the refined molten steel to adjust the nickel content, so that the difference between the nickel content in the adjusted refined molten steel and the target value of nickel content in nickel-containing steel was no greater than 0.005%. After the adjustment was completed, nickel-containing molten steel was prepared.

[0021] The relationship between the mass of the added nickel-iron alloy (m6) and the total mass of the refined molten steel (m5) is as follows:

[0022]

[0023] Where x represents the nickel content of the added nickel-iron alloy;

[0024] b represents the nickel yield, which is not less than 94%.

[0025] According to an embodiment of this application, the adjusting alloy is a nickel-iron alloy.

[0026] According to embodiments of this application, the nickel content of the nickel-iron alloy is not less than 45%.

[0027] According to the embodiments of this application, the oxygen flow rate during converter blowing is controlled at 2000-3000 Nm3 / h, and the oxygen flow rate is reduced to 1500-2000 Nm3 / h in the later stage of blowing.

[0028] This application provides a method for smelting nickel-containing steel using diamond wire. Diamond wire is added to the converter along with scrap steel and molten iron, and the diamond wire is melted by oxygen blowing, thereby ensuring the nickel yield. When the nickel content in the prepared nickel-containing steel reaches the preset target value, the amount of nickel-iron alloy used is greatly reduced, thereby reducing costs and effectively improving production efficiency. Attached Figure Description

[0029] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0030] Figure 1 This is a flowchart of the method for smelting nickel-containing steel using diamond wire provided in this application.

[0031] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0032] The various embodiments or implementation schemes in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments.

[0033] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0034] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0035] The inventors of this application have noticed that there is a waste of resources in discarded diamond wire. If the discarded diamond wire is directly recycled and remelted, it will consume a lot of electricity. However, using it as a nickel source for steel smelting can not only achieve resource recycling, but also reduce the cost of nickel alloying, which is in line with the industrial trend of energy conservation and carbon reduction.

[0036] In view of the above problems, this application provides a method for smelting nickel-containing steel using diamond wire, which can make the nickel content in the prepared nickel-containing steel reach a preset target value and reduce the cost of nickel alloying.

[0037] This application provides a method for smelting nickel-containing steel using diamond wire. Please refer to [link to relevant documentation]. Figure 1 It includes the following steps:

[0038] S100: Diamond wire, scrap steel and molten iron are added to a converter for oxygen blowing smelting to obtain converter steel liquid;

[0039] S200: Transfer the molten steel from the converter to the ladle for deoxidation treatment to obtain deoxidized molten steel;

[0040] S300: The deoxidized molten steel is transferred to the refining furnace for desulfurization and deoxidation to obtain refined molten steel;

[0041] S400: Nickel-modified refined steel liquid to obtain nickel-containing steel liquid;

[0042] S500: Nickel-containing molten steel is continuously cast to obtain nickel-containing steel billets;

[0043] The absolute value of the difference between the actual nickel content in the nickel-containing molten steel and the target nickel content in the nickel-containing molten steel shall not exceed 0.005%.

[0044] This application provides a method for smelting nickel-containing steel using diamond wire. Diamond wire is added to the converter along with scrap steel and molten iron, serving as a nickel source to adjust the nickel content in the molten steel. The diamond wire is melted by oxygen blowing, ensuring a high nickel yield. By achieving a predetermined target nickel content in the prepared nickel-containing steel, the amount of ferronickel alloy used is significantly reduced, thereby lowering costs and effectively improving production efficiency.

[0045] This application uses a large amount of diamond wire for alloying during the converter smelting process and a small amount of nickel-iron alloy for fine-tuning the nickel content during the refining stage in the LF furnace. This ensures the accuracy of the nickel content in the refined molten steel, thereby ensuring that the nickel content in the refined molten steel is consistent with the target value of the nickel content set in the nickel-containing steel grade.

[0046] This application monitors the nickel content in refined molten steel in real time and adjusts the nickel content according to the target value of nickel content in nickel-containing steel, thereby ensuring that the nickel content in the prepared nickel-containing molten steel is consistent with the preset target value of nickel content in nickel-containing steel, and thus ensuring the stability of the nickel content in the final prepared nickel-containing steel.

[0047] In both the diamond wire addition and nickel-iron alloy addition processes, this application controls the nickel yield and thus the loss of nickel during the smelting process, thereby ensuring the stability of the nickel content in the subsequently prepared nickel-containing steel.

[0048] The S100 steps specifically include:

[0049] Prepared by converter blowing: Diamond wire, scrap steel and molten iron are melted and mixed in a converter, and impurities (such as carbon, phosphorus and sulfur) are removed by oxygen blowing smelting, and the nickel element in the diamond wire is fully incorporated into the molten steel.

[0050] For example, waste diamond wire after production line is selected, with a nickel content of not less than 20%.

[0051] In some embodiments, the diamond wire is a pre-treated short segment, with a single segment length of 30-50 cm. Cutting it into 30-50 cm short segments can improve melting efficiency.

[0052] For example, the length of a single segment is 30cm, 32cm, 34cm, 36cm, 38cm, 40cm, 42cm, 44cm, 46cm, 48cm or 50cm.

[0053] In some embodiments, the pretreatment also includes removing oil and impurities from the surface of the diamond wire.

[0054] In some embodiments, the pretreatment also includes drying the diamond wire and scrap steel to prevent the introduction of moisture from causing localized cooling of the molten steel and affecting the nickel leaching efficiency.

[0055] In some embodiments, the oxygen flow rate during converter blowing is controlled at 2000-3000 Nm³ / h, and the oxygen flow rate is reduced to 1500-2000 Nm³ / h in the later stages of blowing. 3 / h.

[0056] 2000-3000 Nm is used in the early stage of blowing. 3 An oxygen flow rate of / h can quickly oxidize and remove impurities such as carbon and phosphorus from molten steel, ensuring smelting efficiency. In the later stage of blowing (when the carbon content is low), reducing the oxygen flow rate can avoid excessive oxidation of molten steel, reduce the loss of nickel elements in diamond wire due to the formation of oxide inclusions, and keep the nickel yield stable at over 94%, laying the foundation for precise control of nickel content in the future.

[0057] For example, when the carbon content is ≤0.2wt%, the oxygen flow rate is reduced.

[0058] For example, the oxygen flow rate in the early stage of blowing is 2000 Nm3 / h, 2200 Nm3 / h, 2400 Nm3 / h, and 2500 Nm3 / h. 3 / h, 2600Nm 3 / h, 2800Nm 3 / h or 3000Nm 3 / h.

[0059] For example, the oxygen flow rate in the later stages of blowing is 1500 Nm3 / h, 1600 Nm3 / h, 1700 Nm3 / h, and 1800 Nm3 / h. 3 / h, 1900Nm 3 / h or 2000Nm 3 / h.

[0060] In this embodiment of the application, low-sulfur and low-phosphorus scrap steel can be selected as the basic raw material for smelting.

[0061] In this embodiment, the molten iron comes from a blast furnace and must meet the requirements of conventional converter smelting for molten iron composition and temperature, such as temperature ≥1300℃, silicon content ≥0.4%, and sulfur content ≤0.04%.

[0062] In some embodiments, the step of adding diamond wire, scrap steel and molten iron to a converter for oxygen blowing smelting to obtain converter molten steel includes: determining the amount of diamond wire added, m1, based on the mass of the converter molten steel, m2, the nickel content of the diamond wire, c1, the weight of the molten iron, m3, the nickel content of the molten iron, c2, the weight of the scrap steel, m4, and the nickel content of the scrap steel, c3.

[0063] After oxygen blowing smelting, the diamond wire, molten iron and scrap steel are completely melted and mixed to form the converter molten steel. The mass of the converter molten steel can be obtained according to the nominal converter capacity. For example, if the smelting equipment is a nominal 210t converter, the mass m2 of the converter molten steel can be set to 210t.

[0064] Molten iron is a basic raw material for smelting. In this embodiment, the molten iron is blast furnace molten iron. Exemplarily, molten iron is added to the converter at a ratio of 60% to 85% of the weight of the molten steel.

[0065] Scrap steel can be used to adjust the composition and total amount of molten steel. For example, scrap steel is added to the converter at a ratio of 20% to 40% of the weight of the molten steel.

[0066] For example, the total weight of molten iron and scrap steel is about 101%-110% of the molten steel in the converter. This is because during the converter blowing process, carbon, manganese and other elements in the molten iron are partially oxidized, and some iron is also oxidized and lost.

[0067] In some embodiments, the amount of diamond wire added, m1, satisfies the following relationship: m2×c5=(m1×c1+m3×c2+m4×c3)×b;

[0068] Where m1 represents the amount of diamond wire added; m2 represents the weight of molten steel in the converter; and m3 represents the weight of molten iron.

[0069] M4 represents the weight of scrap steel; C1 represents the nickel content of the diamond wire, not less than 20%; C2 represents the nickel content of the molten iron; C3 represents the nickel content of the scrap steel; C4 represents the target nickel content of the nickel-containing molten steel; C5 represents 85%-95% of C4; B represents the nickel recovery rate, which is not less than 94%.

[0070] During the smelting process, some nickel is lost due to oxidation, resulting in a nickel content (b) of less than 100%. This step leaves room for nickel adjustment to allow for precise nickel adjustment during the refining process.

[0071] The S200 steps specifically include:

[0072] Deoxidized molten steel is prepared by deoxidation treatment in a ladle, which removes excess oxygen from the converter molten steel, avoids the reaction of oxygen with nickel to form oxide inclusions, and improves the yield of nickel.

[0073] The molten steel from the converter is transferred to a ladle through the tap hole. During the tapping process, argon gas is maintained at the bottom of the ladle to agitate the molten steel and promote uniform mixing.

[0074] In some embodiments, argon gas is continuously blown and stirred at the bottom of the ladle at a flow rate of 250-350 NL / min.

[0075] Bottom-blown argon can flow from the molten steel in the converter through the tapping port into the ladle, and continue until the deoxidizer is added and fully reacted, with argon continuously flowing into the bottom of the ladle throughout the process.

[0076] During steel tapping from the converter, the molten steel is prone to compositional stratification due to flow differences as it enters the ladle. If the nickel in the diamond wire dissolves in the molten steel and is unevenly distributed, it can lead to localized excessively high or low nickel content. Excessive nickel content is easily lost through oxidation, while insufficient nickel content affects subsequent adjustment accuracy. An argon flow rate of 250-350 NL / min provides adequate stirring, ensuring thorough mixing of the dissolved nickel from the diamond wire with the existing molten steel, preventing localized nickel concentration deviations. Simultaneously, it accelerates the deoxidation reaction, reducing secondary nickel oxidation.

[0077] As a solid additive, diamond wire needs to be fully melted in molten steel to release nickel. The convection generated by argon stirring can improve the overall fluidity of the molten steel, promote heat exchange between the diamond wire and the high-temperature molten steel, accelerate its melting process, and ensure that the nickel element enters the molten steel to the maximum extent.

[0078] For example, the argon flow rate is 250 NL / min, 300 NL / min, or 350 NL / min.

[0079] In some embodiments, the step of transferring molten steel from a converter to a ladle for deoxidation treatment to obtain deoxidized molten steel includes: adding a deoxidizing agent to the molten steel from the converter for deoxidation treatment.

[0080] In some embodiments, the amount of deoxidizer added is 0.1-0.6 wt% of the mass of the converter molten steel.

[0081] In some embodiments, the deoxidizer includes one or more of manganese alloys, silicon alloys, and aluminum alloys.

[0082] During converter blowing, oxygen blowing leaves a certain amount of dissolved oxygen in the molten steel. If the amount of deoxidizer added is insufficient, this oxygen cannot be completely consumed, leading to excessive inclusions in the subsequent refining process and affecting the cleanliness of the molten steel. On the other hand, excessive deoxidizer can result in the residue of unreacted alloying elements (such as manganese and silicon), which not only increases raw material costs but may also affect the performance of the steel due to excessive composition. At the same time, excessive deoxidizer may form a large number of high-melting-point inclusions, reducing the purity of the molten steel.

[0083] The dosage can be flexibly adjusted according to the actual oxygen content of the converter steel and the type of deoxidizer to ensure that the oxygen content of the deoxidized steel is ≤50ppm. The higher the oxygen content at the end of the blowing process, the more deoxidizer should be added.

[0084] For example, the amount of deoxidizer added is 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, or 0.6 wt% of the mass of the converter molten steel.

[0085] In some embodiments, the deoxidizer can be weighed from the low-level silo and added all at once during converter tapping. The total amount of deoxidizer required to meet the deoxidation needs of the molten steel is determined and added to the ladle in one go during converter tapping. The natural stirring during the molten steel outflow process, combined with subsequent argon gas stirring, allows the deoxidizer to disperse rapidly and react fully with the oxygen in the molten steel, achieving efficient deoxidation.

[0086] During addition, a coordinated operation of adding and stirring is adopted. The steel convection formed by argon stirring quickly disperses the deoxidizer particles into the interior of the steel, avoiding local accumulation.

[0087] The S300 steps specifically include:

[0088] Refined steel is prepared in a refining furnace to further remove impurities such as sulfur and oxygen from the steel and adjust the temperature of the steel, laying the foundation for precise adjustment of the nickel content in the subsequent process.

[0089] In some embodiments, after the temperature inside the refining furnace reaches the target temperature, desulfurization and deoxidation treatment is performed; the target temperature is 1600-1650℃.

[0090] For example, the target temperature is 1600°C, 1610°C, 1620°C, 1630°C, 1640°C, or 1650°C.

[0091] In some embodiments, the desulfurization and deoxidation treatment includes adding aluminum blocks for deoxidation and adding lime for desulfurization.

[0092] In some embodiments, the amount of aluminum block added is 0.1-0.4 wt% of the mass of the deoxidized molten steel. Exemplarily, the amount of aluminum block added is 0.1 wt%, 0.2 wt%, 0.3 wt%, or 0.4 wt% of the mass of the deoxidized molten steel.

[0093] In some embodiments, the amount of lime added is 0.3-0.6 wt% of the mass of the deoxidized molten steel. Exemplarily, the amount of aluminum block added is 0.3 wt%, 0.4 wt%, 0.5 wt%, or 0.6 wt% of the mass of the deoxidized molten steel.

[0094] The viscosity of molten steel decreases as the temperature increases. The temperature range of 1600-1650℃ allows molten steel to maintain good fluidity, which facilitates the rapid dispersion of materials such as aluminum blocks and lime and their full contact with the molten steel, thus accelerating the mass transfer process of deoxidation and desulfurization reactions.

[0095] If the temperature is below 1600℃, the molten steel will lack fluidity, materials will easily agglomerate, and the reaction will be incomplete. If the temperature is above 1650℃, it will lead to excessive burning of the molten steel, causing alloying elements to volatilize, and may also exacerbate the erosion of the ladle refractory material and introduce impurities. Therefore, 1600-1650℃ is the optimal range that balances reaction efficiency and molten steel stability.

[0096] Aluminum is a strong deoxidizer that can react with trace amounts of residual oxygen in molten steel to generate high-melting-point Al2O3 particles. These particles float to the surface of the molten steel by stirring with argon gas, where they combine with the slag and are removed, achieving deep deoxidation.

[0097] If the amount of aluminum added is insufficient, oxygen in the molten steel cannot be completely removed. Residual oxygen may react with nickel to form NiO inclusions, reducing nickel yield. Excessive aluminum will react with nitrogen in the molten steel to form AlN inclusions, or lead to excessive aluminum content in the steel, affecting the mechanical properties of nickel-containing steels, such as reduced toughness. The amount added can be flexibly adjusted based on the deoxidation effect after tapping from the converter to ensure that the oxygen content in the molten steel after deoxidation is ≤10ppm.

[0098] Lime's main component is CaO, a strong alkaline oxide. It absorbs sulfur from molten steel through a slag-forming reaction, generating low-melting-point CaS which enters the slag to achieve desulfurization. The desulfurization capacity of CaO is significantly enhanced at high temperatures.

[0099] If the amount of lime added is insufficient, desulfurization will be incomplete, and sulfur will react with manganese in the molten steel to form MnS inclusions, affecting the mechanical properties of the steel. Excessive lime will increase the viscosity of the slag, hindering the continued desulfurization reaction, and may also lead to increased inclusions in the molten steel due to unreacted CaO residue. The amount of lime added can be adjusted according to the sulfur content at the time of tapping from the converter, with the goal of reducing the sulfur content of the molten steel to below 0.015%.

[0100] After the temperature reaches the target value, aluminum blocks are added for deoxidation for 5-10 minutes. Once the deoxidation reaction is basically complete, lime is added for desulfurization. Throughout the process, argon gas is used for weak stirring; for example, the argon flow rate is 100-150 NL / min to promote the flotation of Al2O3 and CaS particles, while avoiding secondary oxidation of the molten steel caused by vigorous stirring.

[0101] After the aluminum blocks and lime are added, continue refining for 15-20 minutes to ensure that the deoxidation and desulfurization reactions are fully carried out and the slag and molten steel are completely separated.

[0102] The oxygen and sulfur content in the molten steel is sampled and tested. Once the oxygen content is ≤10ppm and the sulfur content is ≤0.015%, it proceeds to the next process, providing a pure molten steel base for subsequent precise nickel adjustment.

[0103] The S400 steps specifically include:

[0104] Nickel-containing molten steel is prepared through a nickel-adjusting treatment. By precisely calculating and adding adjusting alloys, the nickel content in the molten steel reaches the target value, ensuring that the absolute value of the difference between the actual nickel content and the target value is no greater than 0.005%. Samples of the refined molten steel are taken to determine the nickel content (denoted as d) and the total mass of the refined molten steel (denoted as m5).

[0105] In some embodiments, the step of subjecting refined molten steel to nickel conditioning to obtain nickel-containing molten steel includes:

[0106] Temperature sampling was performed on the refined molten steel to determine its nickel content, which was marked as d. The total mass of the refined molten steel was marked as m5. The nickel content in the refined molten steel was compared with the target value of nickel content in nickel-containing steel. Based on the comparison results, a regulating alloy with a mass of m6 was added to the refined molten steel to adjust the nickel content, so that the difference between the nickel content in the adjusted refined molten steel and the target value of nickel content in nickel-containing steel was no greater than 0.005%. After the adjustment was completed, nickel-containing molten steel was prepared.

[0107] The relationship between the mass of the added nickel-iron alloy (m6) and the total mass of the refined molten steel (m5) is as follows:

[0108] Where x represents the nickel content of the added nickel-iron alloy;

[0109] b represents the nickel yield, which is not less than 94%.

[0110] In some embodiments, the adjusting alloy is a nickel-iron alloy.

[0111] In some embodiments, the nickel content of the nickel-iron alloy is not less than 45%.

[0112] Add the calculated amount of nickel-iron alloy into the LF furnace and keep stirring with argon gas for 5-10 minutes to ensure uniform distribution of nickel.

[0113] The nickel content of the molten steel was tested again to ensure that the absolute value of the difference between the actual nickel content and the target value was ≤0.005%, thus obtaining nickel-containing molten steel.

[0114] The S500 steps specifically include:

[0115] Nickel-containing steel grades are prepared by continuous casting, and the nickel-containing steel liquid is solidified into billets to obtain nickel-containing steel grades that meet the quality requirements.

[0116] The nickel-containing molten steel is soft-blown in the LF furnace at an argon flow rate of 50-100 NL / min for 10-15 minutes to further remove minute inclusions and gases.

[0117] For example, the nickel-containing molten steel after soft blowing is fed into a continuous casting machine and cast at a target casting speed of 1.0-1.5 m / min. The molten steel is cooled in a crystallizer to solidify into a billet, which is then cut and cooled to obtain the nickel-containing steel grade.

[0118] Example

[0119] The following embodiments describe the disclosure of this application in more detail. These embodiments are for illustrative purposes only, as various modifications and variations will be apparent to those skilled in the art within the scope of the disclosure of this application. Unless otherwise stated, all parts, percentages, and ratios reported in the following embodiments are based on mass, and all reagents used in the embodiments are commercially available or synthesized by conventional methods and can be used directly without further processing, and the instruments used in the embodiments are commercially available.

[0120] Example 1

[0121] This embodiment provides a method for smelting nickel-containing steel using diamond wire. In this method, the smelting equipment is a nominal 210t converter, the nickel recovery rate b is 95%, and the target value a of the nickel content in the nickel-containing steel is set to be 0.21%.

[0122] The composition of the diamond wire is shown in Table 1.

[0123] Table 1

[0124]

[0125] As shown in Table 1, the nickel content (c1) of the diamond wire is 22.75%.

[0126] The nickel content (x) of the nickel-iron alloy is 46.25%.

[0127] The method includes the following steps:

[0128] (1) Converter blowing: 165 tons of molten iron, 40 tons of scrap steel and 2 tons of diamond wire are poured into the converter for oxygen blowing to prepare converter steel. The oxygen flow rate is 2500 Nm3 / h in the early stage of blowing and 1600 Nm3 / h in the later stage of blowing. After the blowing is completed, the converter taps the steel, that is, the converter steel flows into the ladle through the tapping port of the converter. After tapping, 200 kg of ferrosilicon manganese, 200 kg of ferrosilicon and 100 kg of aluminum blocks are added for pre-deoxidation to prepare deoxidized steel. During the tapping and deoxidation process, argon gas is introduced for stirring, and the argon gas flow rate is 300 NL / min.

[0129] (2) LF furnace refining: When the ladle enters the LF refining furnace, the weight is 207t. The deoxidized molten steel enters the LF furnace, and 1000kg of lime and 300kg of aluminum blocks are added in batches to form slag for desulfurization and deoxidation. The electrodes are energized and heated to 1620℃. Then, a sample is taken. The test results show that the nickel content is 0.199%. Based on this result, nickel-iron alloy is added to achieve the target composition. According to the calculation formula provided in the embodiment of the present invention, 51.82kg of nickel-iron alloy needs to be added. After stirring with argon for 5 minutes, the temperature is measured and a sample is taken. If the result shows that the difference between the nickel content and the target value does not exceed 0.005%, it indicates that the prepared molten steel is qualified and is marked as nickel-containing molten steel. The nickel-containing molten steel leaves the station and enters the continuous casting process.

[0130] (3) Continuous casting: Nickel-containing molten steel enters the continuous casting table and is cast at the target casting speed to prepare nickel-containing steel.

[0131] The nickel content in the prepared nickel-containing steel was 0.21%, consistent with the target value, indicating that the nickel content in the nickel-containing steel prepared by the rigid method can be precisely controlled.

[0132] This invention provides a method for smelting nickel-containing steel using diamond wire, which can ensure that the nickel content in the prepared nickel-containing steel reaches a preset target value. Specifically, during the addition of diamond wire and nickel-iron alloy, the nickel yield is controlled, thereby controlling the loss of nickel during the smelting process and ensuring the stability of the nickel content in the subsequently prepared nickel-containing steel.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for smelting nickel-containing steel using diamond wire, characterized in that, Includes the following steps: Diamond wire, scrap steel and molten iron are added to a converter for oxygen blowing smelting to obtain converter steel liquid; The molten steel from the converter is transferred to a ladle for deoxidation treatment to obtain deoxidized molten steel. The deoxidized molten steel is transferred to a refining furnace for desulfurization and deoxidation to obtain refined molten steel; The refined steel liquid is subjected to nickel adjustment treatment to obtain nickel-containing steel liquid; The nickel-containing molten steel is subjected to continuous casting to obtain a nickel-containing steel billet; Wherein, the absolute value of the difference between the actual nickel content in the nickel-containing molten steel and the target nickel content in the nickel-containing molten steel is not greater than 0.005%.

2. The method for smelting nickel-containing steel using diamond wire according to claim 1, characterized in that, The step of adding diamond wire, scrap steel and molten iron to a converter for oxygen blowing smelting to obtain converter molten steel includes: determining the amount of diamond wire added, m1, based on the mass of the converter molten steel, m2, the nickel content of the diamond wire, c1, the weight of the molten iron, m3, the nickel content of the molten iron, c2, the weight of the scrap steel, m4, and the nickel content of the scrap steel, c3.

3. The method for smelting nickel-containing steel using diamond wire according to claim 1 or 2, characterized in that, The amount of diamond wire added satisfies the following relationship: m2×c5=(m1×c1+m3×c2+m4×c3)b Where: m1 represents the amount of diamond wire used; m2 represents the weight of molten steel in the converter; m3 represents the weight of molten iron; m4 represents the weight of the scrap steel; c1 indicates that the nickel content of the diamond wire is not less than 20%; c2 indicates the nickel content of the molten iron; c3 indicates the nickel content of the scrap steel; c4 indicates the target nickel content of nickel-containing molten steel; c5 represents 85%-95% of c4; b represents the nickel yield, which is not less than 94%.

4. The method for smelting nickel-containing steel using diamond wire according to claim 1, characterized in that, The step of transferring the molten steel from the converter to a ladle for deoxidation treatment to obtain deoxidized molten steel includes: Argon gas is continuously blown and stirred at the bottom of the ladle at a flow rate of 250-350 NL / min.

5. The method for smelting nickel-containing steel using diamond wire according to claim 1, characterized in that, In the step of adding diamond wire, scrap steel and molten iron to a converter for oxygen blowing smelting to obtain converter steel, the diamond wire is a pre-treated short cut segment with a single segment length of 30-50cm.

6. The method for smelting nickel-containing steel using diamond wire according to claim 1 or 2, characterized in that, The step of transferring the molten steel from the converter to a ladle for deoxidation treatment to obtain deoxidized molten steel includes: adding a deoxidizer to the molten steel from the converter for deoxidation treatment; The amount of deoxidizer added is 0.1-0.6 wt% of the molten steel in the converter.

7. The method for smelting nickel-containing steel using diamond wire according to claim 6, characterized in that, The deoxidizer includes one or more of manganese alloys, silicon alloys, and aluminum alloys.

8. The method for smelting nickel-containing steel using diamond wire according to any one of claims 1-3, characterized in that, The step of transferring the deoxidized molten steel into a refining furnace for desulfurization and deoxidation to obtain refined molten steel includes: After the temperature inside the refining furnace reaches the target temperature, desulfurization and deoxidation treatment is carried out; the target temperature is 1600-1650℃. The desulfurization and deoxidation treatment includes adding aluminum blocks for deoxidation and adding lime for desulfurization.

9. The method for smelting nickel-containing steel using diamond wire according to claim 8, characterized in that, The amount of aluminum block added is 0.2-0.4 wt% of the mass of the deoxidized steel liquid; The amount of lime added is 0.3-0.6 wt% of the mass of the deoxidized molten steel.

10. The method for smelting nickel-containing steel using diamond wire according to claim 3, characterized in that, The step of subjecting the refined molten steel to nickel adjustment to obtain nickel-containing molten steel includes: Temperature sampling was performed on the refined molten steel to determine its nickel content, which was marked as d. The total mass of the refined molten steel was marked as m5. The nickel content in the refined molten steel was compared with the target value of nickel content in nickel-containing steel. Based on the comparison results, an adjusting alloy with a mass of m6 was added to the refined molten steel to adjust the nickel content, so that the difference between the nickel content in the adjusted refined molten steel and the target value of nickel content in nickel-containing steel was no greater than 0.005%. After the adjustment was completed, nickel-containing molten steel was prepared. The relationship between the mass of the added nickel-iron alloy (m6) and the total mass of the refined molten steel (m5) is as follows: ； Where x represents the nickel content of the added nickel-iron alloy; b represents the nickel yield, which is not less than 94%.

11. The method for smelting nickel-containing steel using diamond wire according to claim 10, characterized in that, The regulating alloy is a nickel-iron alloy; the nickel content x of the nickel-iron alloy is not less than 45%.

12. The method for smelting nickel-containing steel using diamond wire according to claim 1, characterized in that, The oxygen flow rate during the initial stage of converter blowing is controlled at 2000-3000 Nm. 3 / h, and the oxygen flow rate is reduced to 1500-2000 Nm in the later stage of blowing. 3 / h.

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