CN113088800B - Method for recycling refining slag and molten steel casting residue of low-carbon aluminum killed steel LF furnace - Google Patents
Method for recycling refining slag and molten steel casting residue of low-carbon aluminum killed steel LF furnace Download PDFInfo
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- C—CHEMISTRY; METALLURGY
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Abstract
The invention belongs to the technical field of metallurgy, and relates to a method for recycling the refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF furnace. The method comprises the following steps: (1) when tapping is carried out by a converter, pouring 60-70wt% of refining slag and molten steel of an upper refining furnace into a ladle waiting for tapping, and pouring the rest 30-40wt% into a slag pot; feeding an aluminum wire during argon blowing; (2) lifting the ladle to an LF refining furnace for refining, and then feeding an aluminum wire and a calcium wire; (3) hoisting the molten steel subjected to the LF refining treatment after the weak blowing to a continuous casting ladle turret to wait for casting; (4) after the ladle is cast in a continuous casting mode, 30-40% of LF refining slag in the ladle is poured into a slag tank, and the rest of LF refining slag and molten steel are poured into the next cycle. The invention ensures that the ladle has a sufficient liquid slag layer when the LF refining is in place, shortens the time of making white slag, saves the consumption of slag making materials and saves one ladle pouring process.
Description
Technical Field
The invention belongs to the technical field of metallurgy, and relates to a method for recycling the refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF furnace.
Background
The LF ladle refining furnace has good refining effect on improving the purity of molten steel, homogenizing the components and temperature of the molten steel and removing non-metallic inclusions in the molten steel, so the LF ladle refining furnace is widely applied to the steel smelting industry. LF ladle refining furnaceThe main principle is that melting flux is heated by electric energy, refining slag has certain reducibility by a deoxidizer, the functions of deoxidizing, desulfurizing, removing impurities and the like of the refining slag on molten steel are promoted, and CaO and Al in LF refining slag 2 O 3 The refining effect of low-sulfur and low-oxygen content of the molten steel is ensured by the characteristics of high content, high alkalinity and strong reducibility, and the residual LF refining slag in the ladle after refining and casting has strong reducibility and desulfurization capability and a large amount of heat, so that the direct discharge is a great resource waste and pollutes the environment. In addition, in order to avoid slag dropping, a certain amount of molten steel remains in the ladle, and the consumption of steel materials is greatly influenced. Therefore, the research on how to utilize the heat, the reducibility and the desulfurization capability of the LF refining slag and reduce the emission is a problem to be solved urgently.
The patent with the application number of 'CN 201910256361.5' discloses a method for utilizing LF refining top slag in a hot state, which comprises the steps of pouring continuous casting residual molten steel and LF refining slag into molten iron treated by KR, and then adding the molten iron and the molten iron into a converter for blowing.
Patent publication No. CN104278131A discloses a method for recycling refining slag, which is to add the refining slag into oxides such as ore to modify, cool and solidify, and recycle the modified refining slag.
The invention patent with publication number CN101956043A discloses a recycling method of steelmaking slag, after the molten steel is poured, firstly 2-3 tons of molten steel are contained in a recycling ladle, then 2 tons of slag are poured into the recycling ladle, and 50kg of covering agent is added. The recovered ladle is transported to an electric furnace process by a transport vehicle, and the residue and the molten iron are poured into the electric furnace together, because the residue is still rich in CaO and Al 2 O 3 And the slag is in a liquid state, and can be poured into an electric furnace to replace lime for dephosphorization and desulfurization, so that the lime consumption is reduced, and meanwhile, the heat in the slag is effectively recycled, the consumption of the electric furnace is reduced, and the pollution to the environment is avoided.
The invention patent with publication number CN101403021A provides a method for utilizing steel slag generated in an electric furnace → LF refining (VD vacuum degassing) → die casting production process flow, wherein a slagging material is added into an LF ladle refining furnace for refining, the slagging material is added into each ton of molten steel for 20kg-50kg, then casting is carried out, the slag of the ladle furnace and the rest molten steel after casting are returned to the electric furnace for smelting, the slagging material is added into the electric furnace, and the slagging material is added into each ton of molten steel for 50kg-70 kg. The addition of slag-making material lime is reduced in the electric furnace smelting process, and the power supply of the electric furnace is reduced. And for steel types needing degassing, refining in an LF ladle refining furnace, adding a slagging material, sending the molten steel to a VD vacuum degassing furnace for degassing after slagging is finished, then casting, and returning the slag of the ladle furnace and the residual molten steel after casting to an electric furnace for smelting.
However, in the above patents, the treatment of the refining slag of the LF ladle is basically performed in the steel-making process links such as a converter, an electric furnace, desulfurization pretreatment or VD and the like, the flow is long, the heat utilization is insufficient, the reducibility and the desulfurization capability of the refining slag of the LF ladle can not be well utilized in the smelting process of the electric furnace, the converter and the like, and in order to prevent sulfur enrichment, the characteristics and functions of the refining slag of the LF ladle are changed by utilizing ores, so that the favorable conditions are finally destroyed, and only the characteristic of high alkalinity is utilized.
Disclosure of Invention
Aiming at the technical problems in the prior art, the invention provides a method for recycling the refining slag and the molten steel casting residue of a low-carbon aluminum killed steel LF furnace.
In order to achieve the purpose, the invention adopts the following specific technical scheme:
a method for recycling refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF furnace is suitable for producing low-carbon aluminum killed steel, and the molten steel has the following components: c: 0.03% -0.07%; si: 0.015% -0.050%; mn: 0.16% -0.25%; s: 0.005% -0.020%; p: 0.007% -0.025%; al: 0.016-0.035%.
The method comprises the following steps: (1) when tapping is carried out by a converter, pouring 60-70wt% of refining slag and the rest of molten steel of the refining slag of an upper refining furnace into a ladle waiting for tapping, and pouring the rest 30-40wt% of refining slag into a slag pot; opening a ladle bottom argon blowing valve immediately and introducing argon; the tapping temperature of the furnace is 1600-1630 ℃; after molten steel discharged from the converter enters a steel ladle for a certain time, adding silicomanganese deoxidized alloy and quicklime along with the molten steel, and increasing argon flow for stirring; after tapping, driving the ladle car to an argon blowing position, and feeding an aluminum wire during argon blowing; (2) lifting the ladle to an LF refining furnace for refining, adjusting the component temperature of molten steel in the LF furnace to 1580-1590 ℃, then feeding an aluminum wire and a calcium wire, adjusting the flow of argon and weakly blowing for more than 8 minutes, and keeping the refining period of the LF furnace for 30-35 min; (3) hoisting the molten steel after the LF refining treatment after the weak blowing to a continuous casting ladle turret to wait for casting; (4) after the ladle is cast in a continuous casting mode, 30-40% of LF refining slag in the ladle is poured into a slag tank, and the rest of LF refining slag and molten steel are poured into the next cycle.
Further, the initial flow rate of argon in the step (1) is controlled to be 0.2-0.4m 3 Min, the increased argon flow is 2.5-3.5m 3 Min; the argon flow is 1.0-1.5m after tapping 3 /min。
Further, feeding 1.3-1.7kg/t of aluminum wire during argon blowing in the step (1).
Further, after molten steel discharged from the converter in the step (1) enters a steel ladle for 30-40t, 1.4-1.8kg/t of silicon-manganese deoxidized alloy is added along with the steel flow, 0.8-1.5kg/t of quick lime is added according to the temperature of the molten steel, 1.5kg/t of quick lime is added when the temperature of the discharged steel from the converter reaches 1630 ℃, the temperature of the discharged steel from the converter is 1600 ℃, and the addition of the quick lime is reduced to 0.8 kg/t.
Further, in the step (2), the refining time of the LF refining furnace is kept between 0.7 and 1.3m 3 Argon flow per min, high-level power transmission for 7-10min, quick lime 4.5-5.5kg/t and efficient fluorite particles 0.8-1.2 kg/t.
Further, when the S content of the refining sample in the step (2) is more than 0.025 percent and the aluminum content is less than 0.010 percent, feeding an aluminum wire of 50-100m into a steel ladle, and feeding a calcium wire of 150-200 m.
Further, in the step (2), the Ar gas flow of the ladle bottom blowing is controlled to be 0.3-0.7m 3 /min。
The invention has the advantages and positive effects that:
1. the invention relates to a method for recycling refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF (ladle furnace), which fully utilizes the refining condition of the tapping of the converter, and advances a part of the refining function of the LF to the tapping process of the converter to complete the refining function, after the continuous casting of a steel ladle is finished, 30-40% of the LF refining slag in the steel ladle is poured into a slag pot, and the rest 60-70% of the refining slag in a molten state and the whole molten steel casting residue are poured into the steel ladle waiting for the tapping of the converter (rather than into an empty steel ladle); then the steel ladle is used for receiving the tapped molten steel, and part of slagging process and deoxidation alloying are carried out in the tapping process by utilizing the heat of the molten steel at the temperature of 1600-1630 ℃, and then the molten steel is refined in an LF furnace. The process fully utilizes the heat contained by 60-70% of molten LF refining slag and the residual heat of continuous casting of molten steel and the reducibility and the desulfurization capability of the molten LF refining slag, so that the steel ladle has a sufficient liquid slag layer when in position in LF refining, the time for making white slag is shortened, the consumption of slag making materials is saved, the electric energy is saved, the electrode consumption is saved, the alloy consumption is saved, the one-time ladle pouring process is saved, the pollution of the discharge of waste slag to the environment is reduced, and the process link is simplified.
2. Because 30-40% of LF refining slag is removed in each circulation, the enrichment and removal of harmful elements are balanced, the problems that the enrichment of harmful elements is easily formed after the LF refining slag is recycled for many times and the LF refining function is weakened are solved, and the LF refining slag is ensured to have a high-efficiency refining function all the time. Meanwhile, in the ladle for recovering the residual molten steel, the link of separating from solid slag is reduced, and the recovery rate is improved.
3. In the invention, after the rest 60-70 percent of LF refining slag and all the molten steel are poured into the steel ladle, the bottom argon blowing valve of the steel ladle is opened immediately, and the argon flow is controlled at 0.3m 3 And/min, preventing the air brick from being stuck by cold slag or cold steel.
4. The refining function of the LF furnace is completed in two stages, the first step is to pre-melt a part of flux lime by using the converter tapping temperature heat, and 0.8-1.5kg/t of ladle quicklime is added in the converter tapping process, so that the converter tapping temperature is required: 1600 ℃ to 1630 ℃ to ensure the heat required by the sufficient melting of the slag; and in the second step of the LF slagging function, 4.5-5.5kg/t of quick lime is added into the LF furnace, and slagging is carried out by electrifying to melt.
5. In order to further promote the slagging speed in the refining process of the LF furnace, 0.8-1.5kg/t of high-efficiency fluorite particles are added into the LF furnace.
6. The method utilizes the temperature heat of converter tapping to melt a part of slag quicklime in advance, so that the refining start time of the molten steel is advanced to the position before the ladle of the LF furnace is in place, the refining period of the LF furnace is shortened to 30-35 min, the refining time is saved, the production rhythm is improved, and the electric energy consumption is saved.
7. The method for deoxidizing the molten steel and the refining slag is mainly realized by a method of feeding 0.8-1.5kg/t of aluminum wire into a ladle after tapping of a converter, and the aluminum wire is fed for 50-100m in an LF refining furnace according to the aluminum content of the molten steel.
8. The tapping temperature of the LF furnace is 1580-1590 ℃ so as to ensure the castability of continuous casting.
9. The method reduces the quantity of the refining slag of the LF furnace which does not participate in circulation to 30-40%, and the refining slag is poured into a slag tank to be discharged, thereby reducing the environmental pollution.
Drawings
FIG. 1 is a schematic flow chart of the cyclic utilization of refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF furnace.
Detailed Description
The technical solution in the embodiment of the present invention will be clearly and completely described below with reference to the embodiment of the present invention; obviously; the described embodiments are only some of the embodiments of the invention; rather than all embodiments. Based on the embodiments of the invention; all other embodiments obtained by a person skilled in the art without making any inventive step; all fall within the scope of protection of the present invention.
As shown in figure 1, the invention discloses a method for recycling refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF furnace, which is suitable for producing low-carbon aluminum killed steel, and comprises the following steps: c: 0.03% -0.07%; si: 0.015% -0.050%; mn: 0.16% -0.25%; s: 0.005% -0.020%; p: 0.007% -0.025%; al: 0.016-0.035%.
Example 1:
the following experiments were carried out in this example using a converter 03-8903 as an example:
A. tapping by a converter: converter blowing terminalThe components: 0.046 percent of C; 0.07 percent of Mn; p: 0.015 percent; 0.039 percent of S; the refining slag of the previous furnace comprises the following components: SiO 2 2 ：8.88％；CaO：57.45％；MgO：7.75％；TFe：0.27％；Al 2 O 3 22.06 percent; 0.27 percent of MnO; binary basicity R 2 : 6.47 times;
the following operations are required when tapping from the converter: pouring about 40wt% of the refining slag of the previous furnace into a slag pot, and pouring the rest of about 1.5t of the refining slag and the rest of molten steel into a ladle waiting for tapping of the furnace (the furnace 03-8903) 5min before tapping of the converter; immediately opening a ladle bottom blowing argon valve, and controlling the flow of argon at 0.2m 3 Min, preventing the air brick from being stuck by cold slag or cold steel, and then driving the ladle car to a converter tapping position to wait for tapping; the tapping temperature of the furnace is 1630 ℃; after molten steel discharged from the converter enters a steel ladle for about 30t, 1.6kg/t of silicomanganese deoxidized alloy is added along with the steel flow, 0.8-1.5kg/t of quicklime is added according to the temperature of the molten steel, 1.5kg/t of quicklime is added when the tapping temperature of the converter reaches 1630 ℃, the tapping temperature of the converter is 1600 ℃, and the addition of the quicklime is reduced to 0.8 kg/t; the flow of argon is opened to 2.5m 3 Strong stirring is carried out every min to promote the melting of quicklime, the melting of cold steel and cold slag at the bottom of a ladle, the uniformity of alloy and the floating of deoxidation products; after tapping, the ladle car is driven to an argon blowing position, and the argon flow is adjusted to 1.0m 3 Min, feeding an aluminum wire at 1.3kg/t during argon blowing, and ensuring the deoxidation of molten steel and the reduction of top slag components;
B. lifting the ladle to an LF refining furnace for refining, wherein the following operations are required during refining: after the slag layer is blown away by the large argon flow, the temperature is measured and the sample is taken, and then the sample is kept at 0.7m 3 The flow rate of argon gas is/min, because the hot LF refining slag left in the upper furnace and the liquid slag formed by adding quicklime into the tapping are thick enough, the power is transmitted for 7 minutes at one time, the temperature and the power are adjusted for 4 minutes, 4.5kg/t of quicklime is added, and 0.8kg/t of high-efficiency fluorite particles are added; according to the composition result of sampling when the LF furnace is refined in place, alloy fine adjustment is carried out, and whether an aluminum wire is fed is determined according to the sulfur content and the aluminum content in the molten steel composition: when the S content of the refining sample is 0.027 percent and the aluminum content is less than 0.009 percent, a 100m aluminum wire (about 0.26kg/t) is fed into a ladle, and a 150m calcium wire (0.45kg/t) is fed after aluminum supplement to promote the denaturation of impurities and the floating of the impurities in the molten steel and are refined by LFSmelting slag and capturing, and simultaneously improving the castability of molten steel in continuous casting; after the calcium wire is fed, the Ar gas flow of the ladle bottom blowing is adjusted to 0.3m 3 Performing weak blowing for 8 minutes in min to ensure that a steel ladle slag layer slightly fluctuates and molten steel is not exposed; adjusting the component temperature of molten steel in the LF furnace to 1580 ℃, and refining for 30 minutes; the refining slag comprises the following terminal components: SiO 2 2 ：8.53％；CaO：60.41％；MgO：8.53％；TFe：0.26％；Al 2 O 3 20.49 percent; 0.26 percent of MnO; binary basicity R 2 : 7.08 times. Molten steel components: 0.057 percent of C; si: 0.027%; mn: 0.19 percent; p: 0.016%; 0.008 percent of S; al (Al) t ：0.022％；
C. Hoisting the molten steel subjected to the LF refining treatment after the weak blowing to a continuous casting ladle turret to wait for casting; and after the ladle finishes continuous casting, pouring 30-40% of LF refining slag in the ladle into a slag pot, and pouring the rest of LF refining slag and molten steel into the next cycle.
Example 2:
the following experiment was carried out in this example using the 03-9229 furnace as an example:
A. tapping by a converter: converter blowing end point composition: 0.039 percent of C; 0.10 percent of Mn; p: 0.019%; 0.035% of S. The refining slag of the previous furnace comprises the following components: SiO 2 2 ：8.33％；CaO：60.48％；MgO：6.59％；TFe：0.43％；Al 2 O 3 19.26 percent; MnO of 0.24 percent; binary basicity R 2 : 7.26 times;
the following operations are required when tapping from the converter: pouring about 30 wt% of the refining slag of the previous furnace into a slag pot, and pouring the rest of the refining slag of 70wt% and the rest of molten steel about 1.2t into a ladle waiting for tapping of the furnace (the furnace 03-9229) 5min before tapping of the converter; immediately opening a ladle bottom blowing argon valve, controlling the flow of argon at 0.4m 3 Min, preventing the air brick from being stuck by cold slag or cold steel, and then driving the ladle car to a converter tapping position to wait for tapping; the tapping temperature of the furnace is 1600 ℃; after molten steel discharged from the converter enters a steel ladle for about 40t, 1.5kg/t of silicomanganese deoxidized alloy is added along with the steel flow, 0.8-1.5kg/t of quicklime is added according to the temperature of the molten steel, 1.5kg/t of quicklime is added when the tapping temperature of the converter reaches 1630 ℃, the tapping temperature of the converter is 1600 ℃, and the addition of the quicklime is reduced to 0.8 kg/t; argon flowThe amount is adjusted to 3.5m 3 Strong stirring is carried out every min to promote the melting of quicklime, the melting of cold steel and cold slag at the bottom of a ladle, the uniformity of alloy and the floating of deoxidation products; after tapping, the ladle car is driven to an argon blowing position, and the argon flow is adjusted to 1.5m 3 Min, feeding an aluminum wire at 1.7kg/t during argon blowing, and ensuring the deoxidation of molten steel and the reduction of top slag components;
B. lifting the ladle to an LF refining furnace for refining, wherein the following operations are required during refining: after the slag layer is blown away by the large argon flow, the temperature is measured and the sample is taken, and then the sample is kept at 1.3m 3 The flow rate of argon gas is/min, because the hot LF refining slag left in the upper furnace and the liquid slag formed by adding quicklime into the tapping are thick enough, power is transmitted for 10 minutes at one time, the temperature and the power are adjusted for 3 minutes, 5.5kg/t of quicklime is added, and 1.2kg/t of high-efficiency fluorite particles are added; and determining whether to feed the aluminum wire according to the sulfur content and the aluminum content in the molten steel components: when the S content of the refining sample is 0.026%, and the aluminum content is 0.008%, feeding an aluminum wire 50m (about 0.26kg/t) and a calcium wire 200m (0.6kg/t) in LF refining; after the calcium wire is fed, the Ar gas flow of the ladle bottom blowing is adjusted to 0.7m 3 Performing weak blowing for 10 minutes in min to ensure that a steel ladle slag layer slightly fluctuates and molten steel is not exposed; adjusting the component temperature of molten steel in the LF furnace to 1590 ℃, and refining for 35 minutes; the refining slag comprises the following terminal components: SiO 2 2 ：9.08％；CaO：55.91％；MgO：7.77％；TFe：0.31％；Al 2 O 3 20.87 percent; 0.25 percent of MnO; binary basicity R 2 : 6.16 times. Molten steel components: 0.047 percent of C; si: 0.037%; mn: 0.19 percent; p: 0.021%; 0.013 percent of S; al (Al) t : 0.024 percent, and the refining period is 34 minutes.
C. Hoisting the molten steel subjected to the LF refining treatment after the weak blowing to a continuous casting ladle turret to wait for casting; after the ladle is cast in a continuous casting mode, 30-40% of LF refining slag in the ladle is poured into a slag tank, and the rest of LF refining slag and molten steel are poured into the next cycle.
The invention relates to a method for recycling refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF (ladle furnace), which fully utilizes the refining condition of converter tapping, and finishes part of refining function of the LF in the process of converter tapping in advance, firstly, after the continuous casting of a ladle is finished, 30-40% of LF refining slag in the ladle is poured into a slag pot, and the rest 60-70% of molten LF refining slag and the whole molten steel casting residue are poured into the ladle waiting for converter tapping (rather than into an empty ladle); then the steel ladle is used for receiving the tapped molten steel, and part of slagging process and deoxidation alloying are carried out in the tapping process by utilizing the heat of the molten steel at the temperature of 1600-1630 ℃, and then the molten steel is refined in an LF furnace. The process fully utilizes the heat contained by 60-70% of molten LF refining slag and the residual heat of continuous casting of molten steel and the reducibility and the desulfurization capability of the molten LF refining slag, so that the steel ladle has a sufficient liquid slag layer when in position in LF refining, the time for making white slag is shortened, the consumption of slag making materials is saved, the electric energy is saved, the electrode consumption is saved, the alloy consumption is saved, the one-time ladle pouring process is saved, the pollution of the discharge of waste slag to the environment is reduced, and the process link is simplified.
Because 30-40% of LF refining slag is removed in each circulation, the enrichment and removal of harmful elements are balanced, the problems that the enrichment of harmful elements is easily formed after the LF refining slag is recycled for many times and the LF refining function is weakened are solved, and the LF refining slag is ensured to have a high-efficiency refining function all the time. Meanwhile, in the ladle for recovering the residual molten steel, the link of separating from solid slag is reduced, and the recovery rate is improved.
The embodiments of the present invention have been described in detail, but the description is only for the preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made within the scope of the present invention shall fall within the scope of the present invention.
Claims (4)
1. A method for recycling refining slag and molten steel casting residue of a low-carbon aluminum killed steel LF furnace is applicable to the low-carbon aluminum killed steel and comprises the following components: 0.03% -0.07%; si: 0.015% -0.050%; mn: 0.16% -0.25%; s: 0.005% -0.020%; p: 0.007% -0.025%; al: 0.016% -0.035%; the method is characterized in that:
the method comprises the following steps: (1) when tapping is carried out by a converter, pouring 60-70wt% of refining slag and the rest of molten steel of the refining slag of an upper refining furnace into a ladle waiting for tapping, and pouring the rest 30-40wt% of refining slag into a slag pot; opening a ladle bottom argon blowing valve immediately and introducing argon; the tapping temperature of the furnace is 1600-1630 ℃; after molten steel discharged from the converter enters a steel ladle for a certain time, adding silicomanganese deoxidized alloy and quicklime along with the molten steel, and increasing argon flow for stirring; after tapping, driving the ladle car to an argon blowing position, and feeding an aluminum wire during argon blowing; (2) lifting the ladle to an LF refining furnace for refining, adjusting the component temperature of molten steel in the LF furnace to 1580-1590 ℃, then feeding an aluminum wire and a calcium wire, adjusting the flow of argon and weakly blowing for more than 8 minutes, and keeping the refining period of the LF furnace for 30-35 min; (3) hoisting the molten steel subjected to the LF refining treatment after the weak blowing to a continuous casting ladle turret to wait for casting; (4) after the ladle is cast in a continuous casting mode, 30-40% of LF refining slag in the ladle is poured into a slag tank, and the rest of LF refining slag and molten steel are poured into the next cycle;
the initial flow of argon in the step (1) is controlled to be 0.2-0.4m 3 Min, increased argon flow rate of 2.5-3.5m 3 Min; the argon flow is 1.0-1.5m after tapping 3 /min；
After molten steel discharged from a converter in the step (1) enters a steel ladle for 30-40t, adding 1.4-1.8kg/t of silicon-manganese deoxidized alloy along with the steel flow, adding 0.8-1.5kg/t of quicklime according to the temperature of the molten steel, adding 1.5kg/t of quicklime when the tapping temperature of the converter reaches 1630 ℃, reducing the adding amount of the quicklime to 0.8kg/t when the tapping temperature of the converter is 1600 ℃, and increasing the adding amount of the quicklime by 0.1kg/t when the tapping temperature rises by 4 ℃;
keeping the refining time of the LF refining furnace in the step (2) to be 0.7-1.3m 3 Argon flow per min, high-level power transmission for 7-10min, quick lime 4.5-5.5kg/t and efficient fluorite particles 0.8-1.2 kg/t.
2. The method for recycling the refining slag and the molten steel casting residue of the low-carbon aluminum killed steel LF furnace as claimed in claim 1, wherein: feeding 1.3-1.7kg/t of aluminum wire during argon blowing in the step (1).
3. The method for recycling the refining slag and the molten steel casting residue of the low-carbon aluminum killed steel LF furnace as claimed in claim 1, wherein: when the S content of the refining sample in the step (2) is more than 0.025 percent and the aluminum content is less than 0.010 percent, a 50-100m aluminum wire is fed into a ladle, and a 150-200m calcium wire is fed into the ladle.
4. The method for recycling the refining slag and the molten steel casting residue of the low-carbon aluminum killed steel LF furnace as claimed in claim 1, wherein: in the step (2), the flow of Ar gas blown from the bottom of the ladle is 0.3-0.7m 3 /min。
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| CN114085952B (en) * | 2021-10-28 | 2023-06-23 | 马鞍山钢铁股份有限公司 | Economical and environment-friendly LF deoxidization slagging method |
| CN114150106A (en) * | 2021-11-17 | 2022-03-08 | 阳春新钢铁有限责任公司 | Novel method for desulfurizing steel ladle by using manganese and calcium |
| CN114480772A (en) * | 2022-01-27 | 2022-05-13 | 日照钢铁控股集团有限公司 | Process for recycling thermal refining slag in converter smelting process |
| CN114540567B (en) * | 2022-03-09 | 2023-05-26 | 天津市新天钢联合特钢有限公司 | Technological method for recycling residual steel slag of continuous casting ladle in converter tapping |
| CN115537501A (en) * | 2022-11-03 | 2022-12-30 | 石横特钢集团有限公司 | Slagging method for adding fluorite and refining pellets in LF (ladle furnace) |
| CN116479214B (en) * | 2023-06-19 | 2023-10-27 | 江苏省沙钢钢铁研究院有限公司 | Synthetic slag and preparation method and application thereof |
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