Method for producing SWRH82B based on vanadium titano-magnetite

Abstract

The invention discloses a method for producing SWRH82B based on vanadium titano-magnetite, and relates to the technical field of steel wire manufacturing. According to the method, a composite blowing technology combining a porous vanadium extraction oxygen lance with bottom blowing inert gas is adopted, and real-time optimization of a coolant ratio is innovatively carried out; kR deep desulfurization, low-sulfur semisteel adding, refining slag alkalinity precise regulation and control and a dual-mode electromagnetic stirring process are combined, the core problems that in the process of smelting the SWRH82B steel through the vanadium titano-magnetite, component fluctuation is sensitive, the purity degree is difficult to control, and the homogeneity of a casting blank is poor are systematically solved, and the process stability and the product quality are remarkably improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of steel wire rod manufacturing, and particularly relates to a method for producing SWRH82B based on vanadium-titanium magnetite. BACKGROUND

[0002] In the traditional process for producing SWRH82B steel from vanadium-titanium magnetite, the endpoint control of the vanadium extraction process is a key link affecting the vanadium recovery rate and the stability of the steel grade. In the traditional vanadium extraction process, when vanadium slag is used as a coolant, the fluctuation of the vanadium pentoxide content and impurities such as phosphorus and sulfur will significantly affect the converter heat balance and the distribution of vanadium elements, leading to deviation of the vanadium extraction endpoint temperature and reduction of the vanadium recovery rate. At the same time, excessive phosphorus and sulfur impurities may be introduced, affecting the purity of the molten steel. In addition, the slag basicity control range is wide in the traditional LF refining, and the continuous casting process has insufficient adaptability, which easily causes the molten steel oxygen activity to be too low or the inclusions to be coarsened, affecting the wire rod drawing performance, leading to center segregation, shrinkage and aggregation of micro-inclusions in the casting blank, and it is difficult to meet the requirements of SWRH82B steel for high homogeneity, especially restricting the subsequent cold upsetting processing qualification rate. SUMMARY

[0003] In view of the defects in the prior art, the application provides a method for producing SWRH82B based on vanadium-titanium magnetite to solve the above technical problems.

[0004] A method for producing SWRH82B based on vanadium-titanium magnetite, comprising the following contents:

[0005] Vanadium-titanium magnetite raw materials and coke are added to a blast furnace for smelting, coal powder is blown through a tuyere, and hot air and oxygen-enriched air are blown in for smelting, to obtain vanadium-containing molten iron with a vanadium content of 0.28-0.35wt%;

[0006] KR desulfurization stirring method is used for desulfurization treatment of the vanadium-containing molten iron, 0.8-1.2kg / t of molten iron of a composite desulfurizer is added, and the stirring time is controlled to be 8-15 minutes;

[0007] The desulfurized molten iron is transferred to a converter, and a multi-hole vanadium extraction oxygen lance is used for combined blowing of top oxygen and bottom inert gas, the endpoint temperature is controlled to be 1380-1420℃, and vanadium slag and semi-steel are obtained;

[0008] The obtained semi-steel is added with clean semi-steel with a sulfur content of ≤0.010% for secondary blowing, the endpoint carbon content is controlled to be 0.70-0.90wt%, and the tapping temperature is controlled to be 1620-1660℃;

[0009] The molten steel tapped is transferred to an LF furnace, active lime and a slag former are added to form a refining slag, the refining slag basicity is controlled to be 1.8-2.5, and 1.2-1.8kg / t of silicon carbide balls are added for diffusion deoxidization;

[0010] The steel billet is obtained by using multi-stage electromagnetic stirring continuous casting process for the deoxygenated refined liquid steel, the pouring temperature is controlled at 1480-1490 ℃, the superheat is 15-25 ℃, the electromagnetic stirring parameters of the crystallizer are current 300-350 A and frequency 3-5 Hz, and the electromagnetic stirring parameters of the end are current 300-350 A and frequency 10-15 Hz.

[0011] By dynamically adjusting the addition range of the desulfurizer and the coolant, and combining with the wide control, the vanadium content reaches 0.28-0.35%, which can buffer the influence of the raw material fluctuation of the vanadium-titanium ore on the composition of the molten iron, reduce the deviation of the terminal temperature of the vanadium extraction, and under the action of the KR desulfurization composite agent and the stirring time, the sulfur content of the liquid steel is stably controlled below 0.005% by breaking through the traditional desulfurization limit, eliminating the “resulfurization” phenomenon, finally, by using multi-stage electromagnetic stirring combined with the precise control of the superheat of 15-25 ℃, the crystallizer electromagnetic stirring and the end electromagnetic stirring are used in the continuous casting process, the ratio of the axial crystal is increased to more than 40%, the center segregation rate is reduced to below 1.0 level of C class, and the requirement of the cold upsetting fracture rate of SWRH82B ≤0.3% is met.

[0012] As preferred, the desulfurized molten iron is transferred into the converter, and the multi-hole vanadium extraction oxygen lance is used for the combined blowing of the top blowing oxygen and the bottom blowing inert gas, which specifically includes the following steps:

[0013] The content of carbon and vanadium in the molten pool is dynamically monitored, and the vanadium slag with V2O5 content of 15-20% used as the coolant is subjected to rapid composition detection before being fed into the furnace;

[0014] According to the real-time detection result of the vanadium slag and the dynamic monitoring result of the molten pool, the addition amount of the vanadium slag coolant is dynamically adjusted through the preset cooling efficiency model, the total addition amount of the coolant in the vanadium extraction blowing process is controlled at 17 kg / t of molten iron, the terminal temperature of the vanadium extraction is ensured to be 1380 ℃, and after the vanadium extraction, the vanadium extraction slag is removed and 4 kg / t of molten iron of the heat generating agent is added.

[0015] Through the dynamic monitoring of the carbon and vanadium content in the molten pool and the rapid composition detection of the vanadium slag, the addition amount of the vanadium slag is adjusted in real time combined with the cooling efficiency model, the excessive oxidation of vanadium caused by overblowing or the excessive vanadium residue in the semi-steel caused by underblowing is avoided, the cooling equivalent of the vanadium slag coolant is dynamically corrected based on the real-time detection of the V2O5 content, the total coolant is strictly controlled at 17 kg / t of molten iron, the vanadium element recovery rate is improved, the input of phosphorus and sulfur impurities is inhibited, the fixed total coolant amount and the quantitative addition of the heat generating agent form a closed loop heat compensation mechanism, the heat efficiency fluctuation of the converter blowing process is reduced, the number of supplementary blowing is reduced, and the oxygen consumption per ton of iron is saved.

[0016] As preferred, the cooling efficiency model is specifically as follows:

[0017] Q slag= β0+ β1V2O5+ β2P + β3S + β4[V] melt + β5[C] melt + δ

[0018] Wherein, Q slag is the vanadium slag coolant addition amount, V2O5 is the mass percentage of vanadium pentoxide in the vanadium slag coolant, P is the mass percentage of phosphorus in the vanadium slag coolant, S is the mass percentage of sulfur in the vanadium slag coolant, [V] melt is the real-time mass percentage of vanadium in the molten pool, [C] melt is the real-time mass percentage of carbon in the molten pool, β0 is a basic coolant requirement constant, β1 is a vanadium pentoxide influence factor, β2 is a phosphorus compensation coefficient, β3 is a sulfur compensation coefficient, β4 is a molten pool vanadium content dynamic adjustment factor, β5 is a molten pool carbon content thermodynamic correction term, and δ is a random error term.

[0019] As preferably, when the obtained semi-steel is added with clean semi-steel with sulfur content ≤0.010% for secondary blowing, the process specifically includes the following steps:

[0020] The content of carbon in the molten pool is dynamically monitored;

[0021] The molten steel is tapped when the carbon content in the molten steel is not less than 0.040% and the molten steel temperature is 1560-1580℃, and the molten steel temperature is controlled at 1500-1520℃ after tapping;

[0022] The molten steel is subjected to bottom argon blowing stirring treatment throughout the tapping process to ensure alloy uniformity;

[0023] The molten steel is subjected to deoxidation and alloying treatment during the tapping process, and active lime and fluorite are added for slagging;

[0024] Low-nitrogen carbon additive is added for carbon enrichment during the tapping process to ensure that the carbon content of the molten steel is 0.75%-0.81% when leaving the station.

[0025] A tapping hole with a diameter of 200mm is used, and a slide plate automatic slag blocking technology is used. During the slagging process, the addition amount of active lime and fluorite is adjusted according to the detected oxide content of SiO2, CaO, etc. in the vanadium slag composition, so as to maintain the target slag basicity and composition, and the carbon content is supplemented by feeding carbon wire at the subsequent argon station to explode the carbon content range.

[0026] As preferably, the tapped molten steel is transferred to an LF furnace, active lime and slagging agent are added to form refining slag, and the refining slag basicity is controlled at 1.8-2.5, which specifically includes the following steps:

[0027] In view of the detected harmful impurities P, S and the like in the vanadium slag, if the content of one or more of P and S exceeds a preset threshold value, the proportion of active lime and fluorite is increased to increase the slag amount, and the preset threshold value is P < 0.02%, S < 0.15%;

[0028] When the temperature of the molten steel reaches 1510°C or above, high-carbon chromium iron is added, and the LF furnace outlet temperature of the molten steel is controlled to be 1550-1560°C.

[0029] When the phosphorus and sulfur in the vanadium slag exceed the standard, the proportion of active lime and fluorite is increased to increase the slag amount and strengthen the adsorption capacity. Based on the slag amount adjustment feedback of vanadium slag impurities, the optimum range of 1.8-2.5 of the refining slag basicity is maintained, the threshold trigger mechanism is used to reduce the addition of excess slag, and at the same time, high-temperature alloying is used to shorten the LF heating time and reduce the power consumption per ton of steel by 30-40 kWh.

[0030] As preferred, when the proportion of active lime and fluorite is increased to increase the slag amount, 3-5 kg / t of lime is added, and 20% of the lime increment is synchronously added with fluorite.

[0031] By quantitatively matching and dynamically maintaining the slag basicity, the fluctuation of the basicity caused by the traditional empirical addition is avoided.

[0032] As preferred, when the temperature of the molten steel reaches 1510°C or above, high-carbon chromium iron is added, the following steps are further included:

[0033] First, 60% of the total amount of high-carbon chromium iron is uniformly sprinkled on the surface of the molten steel, and the chromium content in the molten steel is detected in real time; the remaining high-carbon chromium iron is sprinkled at intervals of 3-5 minutes.

[0034] Generally, when the chromium iron is added for the second time, 0.5-1.0 kg / t of micro-carbon manganese iron is also added synchronously, and the alloying time is shortened by using the synergistic diffusion effect of Mn and Cr.

[0035] As preferred, in the case where the chromium content is below the detection threshold value, the chromium iron is added according to the difference calculation result, and the difference calculation result is calculated by the following formula:

[0036]

[0037] Wherein, K sup is the chromium iron addition amount, Cr goal is the target chromium content, Gr real is the measured chromium content, G is the amount of molten steel, [Cr] melt is the real-time mass percentage of chromium iron, and α is the recovery rate.

[0038] As preferred, during the continuous casting process, the mold cooling water amount is 1900-2100 L / min, and the temperature difference between the inlet and outlet water is 4.7-5.2°C.

[0039] During the continuous casting process, a high-frequency pulse cooling mode with a frequency of 0.5-2 Hz and a duty cycle of 30-70% is used in conjunction with the crystallizer to form a resonance effect and increase the proportion of equiaxed crystals.

[0040] Preferably, during the continuous casting process, pouring is performed at a continuous casting speed of 1.8-2.0 m / min.

[0041] The beneficial effects of the present invention are as follows: in this solution, a composite blowing technology of a porous vanadium-extracting oxygen gun combined with bottom-blowing inert gas is adopted to innovatively optimize the coolant ratio in real time. Combined with KR deep desulfurization, low-sulfur semi-steel addition, precise control of refined slag basicity and dual-mode electromagnetic stirring process, the core problems of sensitive composition fluctuations, difficult purity control and poor homogeneity of ingots in the process of smelting SWRH82B steel from vanadium-titanium magnetite are systematically solved, thereby significantly improving process stability and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0043] Figure 1 The present invention provides a flow chart of a method for producing SWRH82B based on vanadium-titanium magnetite. DETAILED DESCRIPTION

[0044] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0045] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention.

[0046] The embodiments of the invention are described in detail below with reference to the accompanying drawings.

[0047] As shown in Figure 1 A method for producing SWRH82B based on vanadium-titanium magnetite, comprising the following contents:

[0048] Vanadium-titanium magnetite raw materials and coke are added to the blast furnace for smelting, coal powder is injected through the tuyere, and hot air and oxygen-enriched air are blown in for smelting to obtain vanadium-containing molten iron with a vanadium content of 0.28-0.35wt%;

[0049] KR desulfurization stirring method is used for desulfurization treatment of vanadium-containing molten iron, 0.8-1.2kg / t of molten iron of composite desulfurizer is added, and the stirring time is controlled at 8-15 minutes;

[0050] The desulfurized molten iron is transferred to the converter, and the composite blowing of top blowing oxygen and bottom blowing inert gas is carried out by using the porous vanadium extraction oxygen lance, the end point temperature is controlled at 1380-1420℃, and the vanadium slag and semi-steel are obtained;

[0051] The obtained semi-steel is added with clean semi-steel with sulfur content ≤0.010% for secondary blowing, the end point carbon content is controlled at 0.70-0.90wt%, and the tapping temperature is controlled at 1620-1660℃;

[0052] The tapped molten steel is transferred to the LF furnace, active lime and slagging agent are added to form refining slag, the refining slag basicity is controlled at 1.8-2.5, and 1.2-1.8kg / t of silicon carbide balls are added for diffusion deoxidization;

[0053] The molten steel after deoxidizing refining is obtained by using multi-stage electromagnetic stirring continuous casting process, the casting temperature is controlled at 1480-1490℃, the superheat is controlled at 15-25℃, the crystallizer electromagnetic stirring parameters are current 300-350A and frequency 3-5Hz, and the end electromagnetic stirring parameters are current 300-350A and frequency 10-15Hz.

[0054] In this scheme, the composite blowing technology of porous vanadium extraction oxygen lance combined with bottom blowing inert gas is used, the real-time optimization of coolant ratio is innovatively carried out, the KR deep desulfurization, low-sulfur semi-steel addition, precise control of refining slag basicity and double-mode electromagnetic stirring process are combined, the sulfur content in the desulfurized vanadium-containing molten iron is not more than 0.010%, and the core problems such as composition fluctuation sensitivity, purity control difficulty and poor homogeneity of the cast slab in the process of smelting SWRH82B steel from vanadium-titanium magnetite are systematically solved, and the process stability and product quality are significantly improved.

[0055] More specifically, when the desulfurized molten iron is transferred to the converter and the composite blowing of top blowing oxygen and bottom blowing inert gas is carried out by using the porous vanadium extraction oxygen lance, the following steps are included:

[0056] The content of carbon and vanadium in the molten pool is dynamically monitored, and the composition of vanadium slag used as the cooling agent with V2O5 content of 15-20% is rapidly detected before being put into the furnace;

[0057] According to the real-time detection result of the vanadium slag and the dynamic monitoring result of the molten pool, the addition amount of the vanadium slag cooling agent is dynamically adjusted through a preset cooling efficiency model, while the total addition amount of the cooling agent in the vanadium extraction blowing process is controlled to be 17 kg / t of molten iron, so as to ensure that the terminal temperature of the vanadium extraction is 1380℃, and after the vanadium extraction, the vanadium extraction slag is removed and 4 kg / t of molten iron of the heat generating agent is added.

[0058] Through the fusion of the sublance direct detection data and the recalibration analysis of the flue gas composition, at least the detection of V2O5, P and S content is included in the flue gas analysis process, the accurate prediction of the vanadium extraction terminal and the intelligent control of the cooling agent are realized, the problem that the existing technology relies on manual experience to judge the vanadium extraction terminal and the dynamic change response of the carbon and vanadium content in the molten pool is lagged is solved, the overblowing or underblowing phenomenon is reduced, the technical bottleneck of low vanadium recovery rate and large composition fluctuation in the traditional process is broken through, and the stable production of high-quality SWRH82B steel is ensured.

[0059] More specifically, the cooling efficiency model is specifically shown in the following formula:

[0060] Q slag = β0+ β1V2O5+ β2P+ β3S+ β4[V] melt + β5[C] melt + δ

[0061] Wherein, Q slag is the addition amount of the vanadium slag cooling agent, V2O5 is the mass percentage of vanadium pentoxide in the vanadium slag cooling agent, P is the mass percentage of phosphorus in the vanadium slag cooling agent, S is the mass percentage of sulfur in the vanadium slag cooling agent, [V] melt is the real-time mass percentage of vanadium in the molten pool, [C] melt is the real-time mass percentage of carbon in the molten pool, β0 is a basic cooling agent requirement constant, β1 is a vanadium pentoxide influence factor, β2 is a phosphorus compensation coefficient, β3 is a sulfur compensation coefficient, β4 is a molten pool vanadium content dynamic adjustment factor, β5 is a molten pool carbon content thermodynamic correction term, and δ is a random error term.

[0062] Through the model-driven dynamic adjustment of the cooling agent, the dependence on manual experience is eliminated, the semi-steel composition fluctuation range is narrowed, the V2O5 content of the vanadium extraction slag is stabilized at 18-20%, and high-grade raw materials are provided for subsequent vanadium resource utilization.

[0063] More specifically, when the clean semi-steel with sulfur content ≤0.010% is added to the obtained semi-steel for secondary blowing, the following steps are specifically included:

[0064] The content of carbon in the molten pool is dynamically monitored;

[0065] tapping when the carbon content in the molten steel is not less than 0.040% and the temperature of the molten steel is 1560-1580℃, and controlling the temperature of the molten steel at 1500-1520℃ after tapping;

[0066] performing bottom argon blowing stirring treatment on the molten steel throughout the tapping process to ensure alloy uniformity;

[0067] performing deoxidation and alloying treatment on the molten steel during the tapping process, and adding active lime and fluorite to form slag;

[0068] adding low-nitrogen carbon additive to increase carbon content during the tapping process to ensure that the carbon content of the molten steel is 0.75%-0.81% when leaving the station.

[0069] By clean semi-steel addition and dynamic adjustment of the amount of active lime / fluorite, combined with real-time regulation of slag basicity, the "suction" of sulfur element in the secondary blowing stage is avoided, the dynamic monitoring of carbon content and the synergistic application of low-nitrogen carbon additive ensure that the carbon content of the molten steel can be maintained within the required range when leaving the station, the carbon segregation index is reduced by 40%, and at the same time, the nitrogen content is avoided to exceed the standard during the carbonation process, the bottom argon blowing stirring improves the uniformity of alloy elements throughout the process, combined with the adjustment of the slag based on the feedback of the composition of vanadium slag, the stability of the slag basicity is improved, the energy consumption of the LF furnace is reduced, and at the same time, the erosion rate of refractory materials caused by high temperature is avoided.

[0070] More specifically, the molten steel tapped is transferred into the LF furnace, active lime and slag forming agent are added to form refining slag, and when the basicity of the refining slag is controlled at 1.8-2.5, the following steps are included:

[0071] According to the detected harmful impurity content of P and S in the vanadium slag, if the content of one or more of P and S exceeds the preset threshold value, the proportion of active lime and fluorite is increased to increase the amount of slag, and the preset threshold value is P<0.02% and S<0.15%;

[0072] When the temperature of the molten steel reaches 1510℃ or above, high-carbon chromium iron is added, and the LF furnace leaving station temperature of the molten steel is controlled at 1550-1560℃.

[0073] Under high temperature conditions, high-carbon chromium iron is added, the composition and amount of refining slag are appropriately adjusted, and the refining time is extended to strengthen the dephosphorization and desulfurization effect, ensure that the P and S contents in the semi-steel meet the requirements of SWRH82B steel grade, and combined with accurate control of the leaving station temperature, the chromium iron dissolution rate can be ensured to meet the standard, the chromium element recovery rate is improved, and at the same time, chromium segregation caused by low temperature is avoided.

[0074] More specifically, when the proportion of active lime and fluorite is increased to increase the amount of slag, 3-5kg / t of lime is added, and fluorite is added simultaneously according to 20% of the lime increment.

[0075] The quantitative supplement of fluorite can effectively reduce the melting point of the high CaO slag system, improve the mass transfer conditions of slag-gold interface, improve the inclusion adsorption rate, shorten the refining time, and reduce the waste of excess slag.

[0076] More specifically, when the temperature of the molten steel reaches 1510℃ or above, the high-carbon chromium iron is added, and the following steps are further included:

[0077] Firstly, 60% of the total amount of high-carbon chromium iron is uniformly scattered on the surface of the molten steel, and the chromium content in the molten steel is detected in real time; the remaining high-carbon chromium iron is scattered at intervals of 3-5 minutes.

[0078] The phased scattering of high-carbon chromium iron combined with real-time chromium content detection avoids local supersaturation caused by one-time addition, reduces the dissolution rate of chromium element, and narrows the composition fluctuation range.

[0079] More specifically, in the case where the chromium content is below the detection threshold, chromium iron is added according to the difference calculation result, and the difference calculation result is obtained by the following formula:

[0080]

[0081] Wherein, K sup is the chromium iron supplement amount, Cr goal is the target chromium content, Gr real is the measured chromium content, G is the amount of molten steel, [Cr] melt is the real-time mass percentage of chromium iron, and a is the recovery rate.

[0082] More specifically, during the continuous casting process, the crystallizer cooling water amount is 1900-2100L / min, and the temperature difference between the inlet and outlet water is 4.7-5.2℃.

[0083] Accurate control through temperature difference can avoid the deterioration of center segregation caused by local supercooling, and the proportion of equiaxed crystals is increased to 35-40%.

[0084] More specifically, during the continuous casting process, the casting speed is 1.8-2.0m / min.

[0085] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application.

Claims

1. A method for producing SWRH82B based on vanadium-titanium magnetite, characterized in that: The following steps are involved: The vanadium-titanium magnetite raw material and coke are added to a blast furnace for smelting, and pulverized coal is sprayed through a tuyere and hot air and oxygen-enriched air are blown in for smelting to obtain vanadium-containing molten iron with a vanadium content of 0.28-0.35wt%. Use KR desulfurization stirring method to desulfurize vanadium-containing molten iron, add 0.8-1.2kg / t molten iron composite desulfurizer, and control the stirring time to 8-15 minutes; The desulfurized molten iron is transferred to a converter, and a multi-porous vanadium-extracting oxygen lance is used for top-blowing oxygen and bottom-blowing inert gas composite blowing, with the terminal temperature controlled at 1380-1420°C to obtain vanadium slag and semi-steel; Adding clean semi-steel with a sulfur content of ≤0.010% to the obtained semi-steel for secondary blowing, controlling the end point carbon content to 0.70-0.90wt% and the tapping temperature to 1620-1660°C; The tapped molten steel is transferred to the LF furnace, where active lime and slag-forming agent are added to form refined slag. The basicity of the refined slag is controlled at 1.8-2.5, and 1.2-1.8 kg / t steel of silicon carbide balls are added for diffusion deoxidation. The steel liquid after deoxidation and refining is subjected to a multi-stage electromagnetic stirring continuous casting process to obtain steel billets, with the casting temperature controlled at 1480-1490°C and the superheat at 15-25°C. The electromagnetic stirring parameters of the crystallizer are 300-350A current and 3-5Hz frequency, and the terminal electromagnetic stirring parameters are 300-350A current and 10-15Hz frequency.

2. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 1, characterized in that When the desulfurized molten iron is transferred into the converter and a multi-porous vanadium-extracting oxygen lance is used for top-blowing oxygen and bottom-blowing inert gas composite blowing, the process specifically includes the following steps: Dynamically monitor the carbon and vanadium content in the molten pool, and conduct rapid composition testing on vanadium slag with a V2O5 content of 15-20% used as a coolant before it enters the furnace; Based on the real-time detection results of vanadium slag and combined with the dynamic monitoring results of the molten pool, the amount of vanadium slag coolant added is dynamically adjusted through a preset cooling efficiency model. At the same time, a total of 17kg / t of molten iron coolant is added during the vanadium extraction blowing process to ensure that the terminal temperature of vanadium extraction is 1380℃. After vanadium extraction, the vanadium extraction slag is scraped off and 4kg / t of molten iron exothermic agent is added.

3. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 2, characterized in that: The cooling efficiency model is specifically shown in the following formula: Q slag =β0+β1V2O5+β2P+β3S+β4[V] melt +β5[C] melt +d Among them, Q slag is the amount of vanadium slag coolant added, V2O5 is the mass percentage of vanadium pentoxide in the vanadium slag coolant, P is the mass percentage of phosphorus in the vanadium slag coolant, S is the mass percentage of sulfur in the vanadium slag coolant, [V] melt is the real-time mass percentage of vanadium in the molten pool, [C] melt is the real-time mass percentage of carbon in the molten pool, β0 is the basic coolant demand constant, β1 is the vanadium pentoxide influence factor, β2 is the phosphorus compensation coefficient, β3 is the sulfur compensation coefficient, β4 is the dynamic adjustment factor of the vanadium content in the molten pool, β5 is the thermodynamic correction term for the carbon content in the molten pool, and δ is the random error term.

4. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 2, characterized in that: When adding semi-steel having a sulfur content of no more than 0.010% to molten iron after vanadium extraction in a converter for blowing, the method specifically includes the following steps: Dynamically monitor the carbon content in the molten pool; When the carbon content in the molten steel is not less than 0.040% and the molten steel temperature is 1560-1580℃, the steel is tapped. After tapping, the molten steel temperature is controlled at 1500-1520℃. During the whole tapping process, the molten steel is stirred with argon gas at the bottom to ensure the uniformity of the alloy; During the tapping process, the molten steel is deoxidized and alloyed, and active lime and fluorite are added to form slag; During the steel tapping process, low-nitrogen recarburizer is added to increase carbon content to ensure that the carbon content of the molten steel is 0.75%-0.81% when it leaves the station.

5. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 4, characterized in that: When active lime and glass or quartz sand are added for refining and the basicity of the refined slag is controlled at 1.5-2.3, the following steps are specifically included: For the detected harmful impurities such as P and S in the vanadium slag, if the content of one or more elements of P and S exceeds the preset threshold, increase the proportion of active lime and fluorite to increase the slag volume. The preset threshold is P < 0.02% and S < 0.15%; When the temperature of the molten steel reaches above 1510℃, high carbon ferrochrome is added to control the LF furnace outlet temperature of the molten steel to 1550-1560℃.

6. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 5, characterized in that: When increasing the proportion of active lime and fluorite to increase the slag volume, add 3-5kg / t of lime and add fluorite at the same time at 20% of the lime increment.

7. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 5, characterized in that: When the temperature of the molten steel reaches above 1510°C and high carbon ferrochrome is added, the following steps are also included: For the first time, 60% of the total high-carbon ferrochrome was evenly spread on the surface of the molten steel, and the chromium content in the molten steel was detected in real time; Spread the remaining high carbon ferrochrome every 3-5 minutes.

8. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 7, characterized in that: When the chromium content is below the detection threshold, ferrochrome is added according to the difference calculation result, which is calculated by the following formula: Among them, K sup is the amount of ferrochrome added, Cr goal is the target chromium content, Gr real is the measured chromium content, G is the amount of molten steel, [Cr] melt is the real-time mass percentage of ferrochrome, and α is the yield.

9. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 1, characterized in that: During the continuous casting process, the cooling water volume of the crystallizer is 1900-2100L / min, and the temperature difference between the inlet and outlet water is 4.7-5.2℃.

10. The method for producing SWRH82B based on vanadium-titanium magnetite according to claim 1, characterized in that: During the continuous casting process, pouring is performed at a continuous casting speed of 1.8-2.0 m / min.

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