CN115522114A - Method for preparing high-purity medium-high carbon molten steel in short process - Google Patents
Method for preparing high-purity medium-high carbon molten steel in short process Download PDFInfo
- Publication number
- CN115522114A CN115522114A CN202211211935.5A CN202211211935A CN115522114A CN 115522114 A CN115522114 A CN 115522114A CN 202211211935 A CN202211211935 A CN 202211211935A CN 115522114 A CN115522114 A CN 115522114A
- Authority
- CN
- China
- Prior art keywords
- vanadium
- iron
- carbon
- molten iron
- titanium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Abstract
The invention provides a method for preparing high-purity medium-high carbon molten steel in a short process, which comprises the following steps: (1) Mixing the iron ore containing vanadium, an additive and a reducing agent, and roasting at 1150-1300 ℃ for 0.5-6 h to obtain vanadium-containing iron water and titanium-rich slag; (2) Blowing carbon dioxide to the vanadium-containing molten iron in the step (1) for deep impurity removal treatment to obtain impurity-removed molten iron and titanium-containing slag; (3) And (3) blowing mixed gas of carbon dioxide and oxygen into the impurity-removed molten iron in the step (2) for decarburization treatment, and stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 0.25-1.70 wt% to obtain the medium-high carbon molten steel. According to the method, high-quality molten steel with the sulfur content of less than 30ppm, the phosphorus content of less than 50ppm and the titanium content of less than 10ppm can be obtained by only two-step impurity removal processes and through the final decarburization step, so that the high-purity medium-high carbon molten steel can be prepared in a short process, and the method can be used for subsequent smelting of high-quality medium-high carbon steel.
Description
Technical Field
The invention belongs to the field of ferrous metallurgy, relates to a method for preparing medium-high carbon molten steel, and particularly relates to a method for preparing high-cleanliness medium-high carbon molten steel in a short process.
Background
The iron and steel industry is an important basic industry of national economy, is an important support for building modernized strong countries, and is an important field for realizing green low-carbon development. At present, the development of high-end products with high added value and high cleanliness as main attributes increasingly becomes the main technical field of the competition of advanced steel enterprises. Clean steel is a steel grade with very strict control requirements on the content of impurity elements, and the content of sulfur and phosphorus of the clean steel is generally required to be not more than 0.01 percent. When clean steel is smelted, according to the requirements of steel types and purposes, the whole flow of 'pretreatment-steelmaking-refining-continuous casting' of blast furnace molten iron needs to be strictly controlled, and the strict management and control of the cleanliness of steel are realized in a high-efficiency fast-paced production organization mode. High-carbon steel is a high-quality steel with high carbon content, taking high-carbon chromium bearing steel as an example, at present, foreign advanced bearing steel enterprises can control the titanium content to be less than 10ppm, the sulfur content to be less than 20ppm and the phosphorus content to be less than 60ppm, and domestic enterprises still face a small gap.
The iron ore containing vanadium and titanium is a strategic resource which mainly contains iron and is accompanied by a plurality of rare high-value metals such as titanium, vanadium and the like, and is a well-known refractory mineral by taking vanadium-titanium magnetite of Panxi area and Chengde area in China as a typical representative. The current smelting process mainly comprises two types of traditional blast furnace process and non-blast furnace process: the process solves the problem of utilization of iron in the vanadium-titanium magnetite, but the produced titanium slag is low in grade and cannot be efficiently utilized, the steel-making process is heavy in task due to high sulfur and titanium contents in molten iron, and the recovery rate of vanadium elements is low; the non-blast furnace process mainly comprises a direct reduction-electric furnace process, a reduction-grinding process, a sodium treatment vanadium extraction-electric furnace process and the like, and the processes can realize effective separation of iron, vanadium and titanium only through two or even three steps of high temperature, thereby bringing the defects of long process, large investment, high cost, heavy pollution, low comprehensive utilization degree and the like.
In order to realize green high-value utilization of all components of iron, vanadium and titanium in the vanadium-titanium-containing ilmenite, a method for separating iron, vanadium and titanium in vanadium-titanium-iron concentrate through one-step conversion is developed by the research institute of process engineering of the Chinese academy of sciences (CN 106854702B), and comprises the following steps: (1) Mixing and roasting vanadium-titanium-iron ore concentrate and additive with a reducing agent to obtain vanadium-containing pig iron and vanadium-rich titanium materials; (2) Leaching the vanadium-rich titanium material in water, and filtering to obtain a vanadium-containing solution and titanium slag. The process constructs a low-temperature molten multiphase reaction separation new system through sodium-modification reduction coupling, realizes the reduction of iron, the sodium modification of vanadium and the melt separation process of iron and vanadium-rich titanium slag in one step, and produces three products, namely vanadium-containing pig iron, vanadium-containing solution and titanium slag.
The traditional smelting method of medium-high carbon steel is to add carbon powder into molten steel for carburetting operation, CN106435084A discloses a smelting method of ultra-low oxygen medium-high carbon steel, molten iron is pretreated to lead [ S ] to be less than or equal to 0.003 percent and is matched with special low-sulfur steel scrap; the end point [ C ] of the converter is controlled to be 0.1-0.2%, the end point [ S ] is less than or equal to 0.01%, carbon powder is adopted for primary deoxidation before tapping and in the tapping process, 50-65% of the total amount of the carbon powder is added before tapping, and 35-50% of the total amount of the carbon powder is added after tapping is started for 2-4 min. Carbon powder is used for recarburization, carbon burning loss is large, end point carbon content fluctuation is large, impurities such as titanium, silicon, phosphorus, sulfur and the like are inevitably introduced into auxiliary materials, and cleanliness of molten steel is influenced. In order to overcome the defects of the traditional recarburization method of medium-high carbon steel, CN114657311A discloses an operation method for directly smelting variety steel by duplex semisteel, the duplex semisteel is used for replacing the addition amount of a recarburizing agent, the molten steel of medium-high carbon steel is directly added, the used iron water amount is determined according to the contents of carbon, manganese, phosphorus and sulfur at the smelting end point of a converter, and only needed silicon and manganese alloys are added in the deoxidation alloying process. The method is complex to operate, and impurities in the semisteel can be introduced into the molten steel, so that the quality of the molten steel is influenced.
The vanadium extraction semisteel has natural advantages as a molten iron raw material for smelting high-carbon steel. CN113106320A discloses a method for producing medium-high carbon steel 65Mn by alloying molten iron after vanadium extraction, CN111100977A discloses a production method for hot-rolled high carbon steel, and CN102766722A discloses a method for smelting high carbon steel by semi-steel; the 3 methods all utilize the traditional steelmaking process of molten iron desulphurization → converter vanadium extraction → converter smelting → molten iron alloying → LF refining, avoid the loss of other elements such as C content and the like, save steelmaking alloy and reduce production cost. However, the vanadium extraction semisteel is limited by the characteristics of vanadium-titanium magnetite, the steel making process is heavy due to the high sulfur and titanium contents of molten iron, the high cleanliness of the molten iron is difficult to guarantee, and the recovery rate of vanadium is low.
Disclosure of Invention
In order to solve the technical problems, the application provides a method for preparing high-purity medium-high carbon molten steel in a short process by using vanadium-titanium-containing ilmenite, and the method can obtain high-quality molten steel with the sulfur content of lower than 30ppm, the phosphorus content of lower than 50ppm and the titanium content of lower than 10ppm by only two-step impurity removal process and the final decarburization step, so that the high-purity medium-high carbon molten steel is prepared in a short process and can be used for subsequent smelting of high-quality medium-high carbon steel.
In order to achieve the technical effect, the invention adopts the following technical scheme:
the invention provides a method for preparing high-purity medium-high carbon molten steel in a short process, which comprises the following steps:
(1) Mixing the iron ore containing vanadium, an additive and a reducing agent, and roasting at 1150-1300 ℃ for 0.5-6 h to obtain vanadium-containing iron water and titanium-rich slag;
(2) Blowing carbon dioxide to the vanadium-containing molten iron in the step (1) for deep impurity removal treatment to obtain impurity-removed molten iron and titanium-containing slag;
(3) And (3) blowing mixed gas of carbon dioxide and oxygen into the impurity-removed molten iron in the step (2) for decarburization treatment, and stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 0.25-1.70 wt% to obtain the medium-high carbon molten steel.
Wherein, the temperature of the step (1) firing may be 1160 ℃, 1170 ℃, 1180 ℃, 1190 ℃, 1200 ℃, 1210 ℃, 1220 ℃, 1230 ℃, 1240 ℃, 1250 ℃, 1260 ℃, 1270 ℃, 1280 ℃, or 1290 ℃, etc., the time of the step (1) firing may be 0.6h, 0.75h, 1.0h, 1.25h, 1.5h, 1.75h, 2.0h, 2.25h, 2.5h, 2.75h, 3.0h, 3.25h, 3.5h, 3.75h, 4.0h, 4.25h, 4.5h, 4.75h, 5.0h, 5.25h, 5.5h, 5.9h, etc., the content of carbon in the step (3) may be 0.30wt%, 0.35wt%, 0.40wt%, 0.50wt%, 0.60wt%, 0.70wt%, 0.80wt%, 0.90wt%, 1.00wt%, or 1.0%, etc., and the above-recited values are not limited to 1.30wt%, 1.35 wt%, 1.10%, or more.
In the invention, the sodium modification system has extremely strong advantages of phosphorus, sulfur and titanium, and can obtain vanadium-containing molten iron with low phosphorus, sulfur and titanium from vanadium-containing ilmenite in one step, the main characteristic of the molten iron is that the content of phosphorus and sulfur is extremely low, and the content of titanium and silicon in the molten iron is also very low and is far lower than that of the molten iron of a conventional blast furnace or other direct reduction processes, so that the impurities such as sulfur, phosphorus, titanium, silicon and the like can be controlled to be extremely low level from the source of the molten iron without the traditional 'three-removal of molten iron' pretreatment process, a high-purity molten iron base material is provided for a steelmaking process, and the impurity removal burden in the steelmaking process is reduced; in order to further improve the purity of the molten iron, CO is selected 2 Deeply removing impurities and decarbonizingCan reduce the blowing end point [ O ]]The concentration of the high-purity medium-high carbon molten steel is realized by a short process, and the high-purity medium-high carbon molten steel can be used for subsequent smelting of high-quality medium-high carbon steel.
In the invention, the temperature of the sodium reduction roasting in the step (1) is limited to 1150-1300 ℃, the time is limited to 0.5-6 h, and the conditions of the sodium reduction roasting are further optimized. The main reason is that proper reduction temperature and time are important factors for ensuring that the content of impurities such as phosphorus, sulfur, titanium and the like in the molten iron is low; when the roasting temperature is too low, slag iron cannot be fully separated, and when the roasting temperature is too high, excessive phosphorus, sulfur and titanium elements can be reduced to enter molten iron; when the roasting time is insufficient, slag and iron are badly separated, and the property of the slag is changed due to overlong roasting time, so that the impurity content in the molten iron exceeds the standard, and the difficulty is increased for the subsequent impurity removal process.
In the invention, in the smelting process, the oxidation reaction sequence of various elements in the molten iron at a low-temperature stage (such as 1300 ℃) is Ti, si, P, V, cr, mn and C; the carbon oxidation reaction starts as the temperature increases, and the oxidation reaction occurs in the high temperature stage (e.g., 1600 ℃) in the order of C, ti, si, V, cr, mn. Based on the principle, the step-by-step proceeding of impurity removal and decarburization can be realized. O is 2 Strong oxidizability, violent reaction during blowing and end point of molten steel [ C ]]The content is not easy to control, and a carburant needs to be added in the later period. CO 2 2 The oxidability is weak, the reaction is mild during blowing, carbon is hardly lost in the low-temperature impurity removal stage, and harmful impurities are basically removed completely; in the high-temperature decarburization stage, the carbon loss is slow, and the end point content of carbon is easy to control. Due to CO 2 + C =2CO is an endothermic reaction, resulting in a decrease in the temperature of molten steel, and therefore, in the high-temperature decarburization stage, a certain proportion of O may be mixed 2 The decarburization rate and the molten steel temperature are controlled.
As a preferred technical solution of the present invention, the vanadium-containing iron ore of step (1) includes any one or a combination of at least two of vanadium titano-magnetite, vanadium titano-iron concentrate, vanadium-containing iron concentrate or vanadium-containing ilmenite, and the combination is exemplified by, typically but not limited to: the combination of vanadium titano-magnetite and vanadium titano-iron concentrate, the combination of vanadium titano-iron concentrate and vanadium-containing iron concentrate, the combination of vanadium-containing iron concentrate and vanadium-containing ilmenite, the combination of vanadium-containing ilmenite and vanadium titano-magnetite or the combination of vanadium titano-magnetite, vanadium titano-iron concentrate and vanadium-containing iron concentrate, etc.
Preferably, the additive of step (1) comprises any one or a combination of at least two of sodium hydroxide, sodium carbonate or sodium bicarbonate, typical but non-limiting examples being: combinations of sodium hydroxide and sodium carbonate, sodium carbonate and sodium bicarbonate, sodium bicarbonate and sodium hydroxide, or sodium hydroxide, sodium carbonate and sodium bicarbonate, and the like.
Preferably, the reducing agent of step (1) comprises any one of coal, coke or graphite or a combination of at least two of the following, typical but non-limiting examples being: a combination of coal and coke, a combination of coke and graphite, a combination of graphite and coal, or a combination of coal, coke and graphite, and the like.
As a preferred embodiment of the present invention, the mass ratio of the vanadium-containing iron ore in step (1) to the additive is 100 (50 to 100), such as 100.
Preferably, in step (1), the mass ratio of the vanadium-containing iron ore to the reducing agent is 100 (25 to 40), such as 100.
As a preferable technical scheme of the invention, in the vanadium-containing molten iron in the step (1), the mass percent of iron is 90-96%, the mass percent of carbon is 3-5%, the mass percent of vanadium is 0.05-1.5%, the mass percent of titanium is 0.03-0.001%, the mass percent of phosphorus is 0.005-0.0002%, and the mass percent of sulfur is 0.003-0.0002%.
The mass percentage of iron may be 91%, 92%, 93%, 94%, or 95%, the mass percentage of carbon may be 3.2%, 3.5%, 3.8%, 4%, 4.2%, 4.5%, or 4.8%, the mass percentage of titanium may be 0.002%, 0.005%, 0.01%, 0.015%, 0.02%, 0.025%, or 0.029%, the mass percentage of phosphorus may be 0.0005%, 0.001%, 0.0015%, 0.002%, 0.0025%, 0.003%, 0.0035%, 0.004%, or 0.0045%, and the like, and the mass percentage of sulfur may be 0.0005%, 0.001%, 0.0015%, 0.002%, or 0.0025%, and the like, but is not limited to the above-mentioned settings, and other values not listed in the above-mentioned value ranges are also applicable.
As a preferred embodiment of the present invention, the temperature of the deep impurity removal treatment in step (2) is 1200 to 1450 ℃, such as 1220 ℃, 1250 ℃, 1280 ℃,1300 ℃, 1320 ℃, 1350 ℃, 1380 ℃, 1400 ℃, 1430 ℃ and the like, but is not limited to the above-mentioned settings, and other values not listed in the numerical range are also applicable.
Preferably, the time of the deep impurity removal treatment in the step (2) is 5-20 min, such as 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min or 19min, etc., but is not limited to the enumerated setting, and other non-enumerated values in the numerical range are also applicable.
As a preferable embodiment of the present invention, the flow rate of the carbon dioxide gas to be blown in the step (2) is 0.5 to 5Nm 3 /t Molten iron Min, e.g. 1Nm 3 /t Molten iron ·min、1.5Nm 3 /t Molten iron ·min、2Nm 3 /t Molten iron ·min、2.5Nm 3 /t Molten iron ·min、3Nm 3 /t Molten iron ·min、3.5Nm 3 /t Molten iron ·min、4Nm 3 /t Molten iron Min or 4.5Nm 3 /t Molten iron Min, etc., but are not limited to the recited settings, and other non-recited values within the numerical range are equally applicable.
In the present invention, the CO in the step (2) 2 The gas can adopt pure CO 2 Gas, or using CO 2 Gas volume ratio is not less than 50%, and the rest is Ar or N 2 Mixed gas of inert gas; said CO 2 Reference GB/T6052-2011 industrial liquid for gas raw material gasThe carbon dioxide is carried out according to the standard, and sulfides and phosphide are not required to exceed the standard; the blowing mode adopts top blowing, bottom blowing, side blowing or top-bottom combined blowing and other modes.
As a preferred embodiment of the present invention, the temperature of the decarburization treatment in the step (3) is 1500 to 1700 ℃, for example 1520 ℃, 1550 ℃, 1580 ℃,1600 ℃, 1620 ℃, 1650 ℃ or 1680 ℃, but the invention is not limited to the above-mentioned setting, and other values not shown in the numerical range are also applicable.
As a preferable embodiment of the present invention, the flow rate of the mixed gas of carbon dioxide and oxygen to be blown in the step (3) is 0.5 to 5Nm 3 /t Molten iron Min, e.g. 1Nm 3 /t Molten iron ·min、1.5Nm 3 /t Molten iron ·min、2Nm 3 /t Molten iron ·min、2.5Nm 3 /t Molten iron ·min、3Nm 3 /t Molten iron ·min、3.5Nm 3 /t Molten iron ·min、4Nm 3 /t Molten iron Min or 4.5Nm 3 /t Molten iron Min, etc., but are not limited to the recited settings, and other non-recited values within the numerical range are equally applicable.
In the present invention, the blowing in step (3) may be performed using CO 2 And O 2 Mixed gas in any proportion, or CO 2 And O 2 The volume fraction of the mixed gas is not less than 50% in any proportion, and the rest is Ar or N 2 Mixed gas of inert gas; said CO 2 The gas raw material gas is executed according to the GB/T6052-2011 Industrial liquid carbon dioxide standard, and sulfides and phosphide cannot exceed the standard; the blowing mode adopts top blowing, bottom blowing, side blowing or top-bottom combined blowing and the like.
As a preferable technical scheme of the invention, in the medium-high carbon molten steel in the step (3), the mass percent of carbon is 0.25-1.70%, the mass percent of titanium is 0.001-0.00001%, the mass percent of phosphorus is 0.005-0.0002%, the mass percent of sulfur is 0.003-0.0002%, and the balance is iron, conventional elements and other residual elements.
The mass percentage of carbon may be 0.30%, 0.35%, 0.40%, 0.50%, 0.60%, 0.70%, 0.80%, 0.90%, 1.00%, 1.10%, 1.20%, 1.30%, 1.40%, 1.50%, 1.60%, etc., the mass percentage of titanium may be 0.00005%, 0.0001%, 0.0002%, 0.0005%, 0.0008%, 0.001%, etc., the mass percentage of phosphorus may be 0.0005%, 0.001%, 0.0015%, 0.002%, 0.0025%, 0.003%, 0.0035%, 0.004%, 0.0045%, etc., the mass percentage of sulfur may be 0.0005%, 0.001%, 0.0015%, 0.002%, 0.0025%, etc., but the present invention is not limited thereto, and other values not recited in the above ranges of values are also applicable.
As a preferable technical scheme of the invention, the method for preparing the high-purity medium-high carbon molten steel in the short process comprises the following steps:
(1) Mixing vanadium-containing iron ore, additive and reducing agent according to the mass ratio of 100 (50-100) to 25-40, and roasting at 1150-1300 ℃ for 0.5-6 h to obtain vanadium-containing iron water and titanium-rich slag;
(2) Blowing carbon dioxide into the vanadium-containing molten iron in the step (1) at 1200-1450 ℃ for deep impurity removal treatment for 5-20 min, wherein the flow of the blown carbon dioxide is 0.5-5 Nm 3 /t Molten iron Min, obtaining impurity-removed molten iron and titanium-containing slag;
(3) Blowing mixed gas of carbon dioxide and oxygen into the molten iron subjected to impurity removal in the step (2) at 1500-1700 ℃ for decarburization treatment, wherein the flow rate of the mixed gas of the carbon dioxide and the oxygen is 0.5-5 Nm 3 /t Molten iron And min, stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 0.25-1.70%, and obtaining the medium-high carbon molten steel.
Compared with the prior art, the invention has at least the following beneficial effects:
the method can obtain high-quality molten steel with the sulfur content of less than 30ppm, the phosphorus content of less than 50ppm and the titanium content of less than 10ppm by only two-step impurity removal process and the final decarburization step, realizes the short-process preparation of the high-purity high-carbon molten steel, and can be used for subsequent smelting of high-quality high-carbon steel.
Detailed Description
For the purpose of facilitating an understanding of the present invention, the present invention will now be described by way of examples. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitation of the present invention.
Example 1
The embodiment provides a method for preparing high-purity medium-high carbon molten steel in a short process, which comprises the following steps:
(1) Mixing vanadium titano-magnetite, sodium hydroxide and coke according to a mass ratio of 100;
the vanadium-containing molten iron comprises 94.26% of iron, 3.6% of carbon, 0.0172% of titanium, 0.0014% of phosphorus and 0.0002% of sulfur by mass;
(2) Blowing pure carbon dioxide to the vanadium-containing molten iron in the step (1) at 1200 ℃ for deep impurity removal treatment for 20min, wherein the flow of the blown carbon dioxide is 0.5Nm 3 /t Molten iron Min, separating gold slag to obtain impurity-removed molten iron and titanium-containing slag;
(3) Blowing a mixed gas of carbon dioxide and oxygen (with a volume ratio of 1:1) into the molten iron subjected to impurity removal in the step (2) at 1500 ℃ to perform decarburization treatment, wherein the flow rate of the mixed gas of the carbon dioxide and the oxygen is 0.5Nm 3 /t Molten iron Min, stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 1.70%, and separating gold slag to obtain the medium-high carbon molten steel;
the mass percent of carbon in the medium-high carbon molten steel is 1.70%, the mass percent of titanium is 0.0007%, the mass percent of phosphorus is 0.0028%, the mass percent of sulfur is 0.0005%, and the balance of iron, conventional elements and other residual elements.
Example 2
The embodiment provides a method for preparing high-purity medium-high carbon molten steel in a short process, which comprises the following steps:
(1) Mixing vanadium titano-magnetite, sodium bicarbonate and graphite according to a mass ratio of 100;
the vanadium-containing molten iron contains 95.33% by mass of iron, 3.2% by mass of carbon, 0.0126% by mass of titanium, 0.0034% by mass of phosphorus and 0.0017% by mass of sulfur;
(2) Blowing pure carbon dioxide to the vanadium-containing molten iron in the step (1) at 1400 ℃ for deep impurity removal treatment for 5min, wherein the flow of the blown carbon dioxide is 5Nm 3 /t Molten iron Min, separating gold slag to obtain impurity-removed molten iron and titanium-containing slag;
(3) Blowing a mixed gas of carbon dioxide and oxygen (with a volume ratio of 1:1) into the molten iron subjected to impurity removal in the step (2) at 1700 ℃ to perform decarburization treatment, wherein the flow rate of the mixed gas of the carbon dioxide and the oxygen is 5Nm 3 /t Molten iron Min, stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 0.25%, and separating gold slag to obtain the medium-high carbon molten steel;
the mass percent of carbon in the medium-high carbon molten steel is 0.25%, the mass percent of titanium is 0.0004%, the mass percent of phosphorus is 0.00036%, the mass percent of sulfur is 0.0021%, and the balance is iron, conventional elements and other residual elements.
Example 3
The embodiment provides a method for preparing high-purity medium-high carbon molten steel in a short process, which comprises the following steps:
(1) Mixing vanadium-titanium magnetite, sodium carbonate and coke according to a mass ratio of 100;
the vanadium-containing molten iron comprises 96.44% by mass of iron, 3.5% by mass of carbon, 0.0019% by mass of titanium, 0.0008% by mass of phosphorus and 0.0003% by mass of sulfur;
(2) Injecting pure carbon dioxide into the vanadium-containing molten iron in the step (1) at 1350 ℃ for deep impurity removal treatment for 12min, wherein the flow of the injected carbon dioxide is 2Nm 3 /t Molten iron Min, separating gold slag to obtain impurity-removed molten iron and waterTitanium slag;
(3) Blowing a mixed gas of carbon dioxide and oxygen (the volume ratio is 1:1) to the molten iron subjected to impurity removal in the step (2) at 1600 ℃ for decarburization treatment, wherein the flow rate of the mixed gas for blowing the carbon dioxide and the oxygen is 2Nm 3 /t Molten iron Min, stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 0.5%, and separating gold slag to obtain the vanadium-containing medium-high carbon molten steel;
the mass percent of carbon in the medium-high carbon molten steel is 0.5%, the mass percent of titanium is 0.0001%, the mass percent of phosphorus is 0.0011%, the mass percent of sulfur is 0.0006%, and the balance of iron, conventional elements and other residual elements.
Example 4
This example was carried out under the same conditions as in example 3 except that the calcination temperature in step (1) was 1250 ℃ for 5 hours.
The mass percent of carbon in the medium-high carbon molten steel is 0.5%, the mass percent of titanium is 0.0002%, the mass percent of phosphorus is 0.0012%, the mass percent of sulfur is 0.0009%, and the balance of iron, conventional elements and other residual elements.
Comparative example 1
This comparative example was carried out under the same conditions as in example 3 except that the calcination temperature in step (1) was 1400 ℃.
The mass percent of carbon in the medium-high carbon molten steel is 0.5%, the mass percent of titanium is 0.0003%, the mass percent of phosphorus is 0.0076%, the mass percent of sulfur is 0.0024%, and the balance of iron, conventional elements and other residual elements.
Comparative example 2
This comparative example was conducted under the same conditions as in example 3 except that the calcination time in step (1) was 10 hours.
The vanadium-containing medium-high carbon molten steel contains 0.5% of carbon, 0.0007% of titanium, 0.0103% of phosphorus, 0.0037% of sulfur and the balance of iron, conventional elements and other residual elements.
Comparative example 3
This comparative example was conducted under the same conditions as in example 3 except that the temperature for removing impurities in step (2) was 1500 ℃.
The mass percent of carbon in the medium-high carbon molten steel is 0.5%, the mass percent of titanium is 0.0016%, the mass percent of phosphorus is 0.0013%, the mass percent of sulfur is 0.0010%, and the balance of iron, conventional elements and other residual elements.
The applicant states that the present invention is illustrated by the above examples to show the detailed process equipment and process flow of the present invention, but the present invention is not limited to the above detailed process equipment and process flow, i.e. it does not mean that the present invention must rely on the above detailed process equipment and process flow to be implemented. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.
Claims (10)
1. The method for preparing high-purity medium-high carbon molten steel in a short process is characterized by comprising the following steps of:
(1) Mixing the iron ore containing vanadium, an additive and a reducing agent, and roasting at 1150-1300 ℃ for 0.5-6 h to obtain vanadium-containing iron water and titanium-rich slag;
(2) Blowing carbon dioxide to the vanadium-containing molten iron in the step (1) for deep impurity removal treatment to obtain impurity-removed molten iron and titanium-containing slag;
(3) And (3) blowing mixed gas of carbon dioxide and oxygen into the impurity-removed molten iron in the step (2) for decarburization treatment, and stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 0.25-1.70 wt% to obtain the medium-high carbon molten steel.
2. The method of claim 1, wherein the vanadium-containing iron ore of step (1) comprises any one of or a combination of at least two of vanadium titano-magnetite, vanadium-titanium-iron concentrate, vanadium-containing iron concentrate, or vanadium-containing ilmenite;
preferably, the additive in step (1) comprises any one of sodium hydroxide, sodium carbonate or sodium bicarbonate or a combination of at least two of the sodium hydroxide, the sodium carbonate or the sodium bicarbonate;
preferably, the reducing agent in step (1) comprises any one of coal, coke or graphite or a combination of at least two of the above.
3. The method according to claim 1 or 2, characterized in that the mass ratio of the vanadium-containing iron ore in the step (1) to the additive is 100 (50-100);
preferably, the mass ratio of the vanadium-containing iron ore to the reducing agent in the step (1) is 100 (25-40).
4. The method according to any one of claims 1 to 3, wherein the molten iron containing vanadium in the step (1) comprises 90 to 96% by mass of iron, 3 to 5% by mass of carbon, 0.05 to 1.5% by mass of vanadium, 0.03 to 0.001% by mass of titanium, 0.005 to 0.0002% by mass of phosphorus, and 0.003 to 0.0002% by mass of sulfur.
5. The method according to any one of claims 1 to 4, wherein the temperature of the deep impurity removal treatment in the step (2) is 1200 to 1450 ℃;
preferably, the time of the deep impurity removal treatment in the step (2) is 5-20 min.
6. The method according to any one of claims 1 to 5, wherein the flow rate of the carbon dioxide gas to be injected in the step (2) is 0.5 to 5Nm 3 /t Molten iron ·min。
7. The method according to any one of claims 1 to 6, wherein the temperature of the decarburization treatment in step (3) is 1500 to 1700 ℃.
8. The method as claimed in any one of claims 1 to 7, wherein the flow rate of the mixed gas of carbon dioxide and oxygen to be injected in the step (3) is 0.5 to 5Nm 3 /t Molten iron ·min。
9. The method according to any one of claims 1 to 8, wherein the mass percent of carbon in the medium-high carbon molten steel in the step (3) is 0.25 to 1.70%, the mass percent of titanium is 0.001 to 0.00001%, the mass percent of phosphorus is 0.005 to 0.0002%, the mass percent of sulfur is 0.003 to 0.0002%, and the balance is iron, conventional elements and other residual elements.
10. Method according to any of claims 1-9, characterized in that the method comprises the steps of:
(1) Mixing vanadium-containing iron ore, additive and reducing agent according to the mass ratio of 100 (50-100) to 25-40, and roasting at 1150-1300 ℃ for 0.5-6 h to obtain vanadium-containing iron water and titanium-rich slag;
(2) Blowing carbon dioxide into the vanadium-containing molten iron in the step (1) at 1200-1450 ℃ for deep impurity removal treatment for 5-20 min, wherein the flow of the blown carbon dioxide is 0.5-5 Nm 3 /t Molten iron Min, obtaining impurity-removed molten iron and titanium-containing slag;
(3) Blowing mixed gas of carbon dioxide and oxygen into the molten iron subjected to impurity removal in the step (2) at 1500-1700 ℃ for decarburization treatment, wherein the flow rate of the mixed gas of the carbon dioxide and the oxygen is 0.5-5 Nm 3 /t Molten iron And min, stopping blowing when the carbon content in the impurity-removed molten iron is reduced to 0.25-1.70%, and obtaining the medium-high carbon molten steel.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2022111768160 | 2022-09-26 | ||
| CN202211176816 | 2022-09-26 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115522114A true CN115522114A (en) | 2022-12-27 |
| CN115522114B CN115522114B (en) | 2023-09-12 |
Family
ID=84701673
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211211935.5A Active CN115522114B (en) | 2022-09-26 | 2022-09-30 | Method for preparing high-cleanliness medium-high carbon steel liquid in short process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115522114B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102352423A (en) * | 2011-10-20 | 2012-02-15 | 攀枝花慧泰金属新材料有限公司 | Method for selecting and smelting titanium from vanadium titanomagnetite at low temperature |
| CN106167845A (en) * | 2016-09-27 | 2016-11-30 | 东北大学 | A kind of winding-up CO2or the method for carbon in limestone removing vanadium-bearing hot metal |
| CN106854702A (en) * | 2015-12-09 | 2017-06-16 | 中国科学院过程工程研究所 | The method that the conversion of one step separates iron, vanadium and titanium in sefstromite concentrate |
| CN108048618A (en) * | 2018-01-29 | 2018-05-18 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of converter CO2The method of vanadium extraction |
| CN109943719A (en) * | 2019-04-19 | 2019-06-28 | 冉显俊 | The method for preparing titanium slag and pig iron containing vanadium simultaneously as raw material using vanadium titano-magnetite |
| US20200340070A1 (en) * | 2018-11-07 | 2020-10-29 | University Of Science And Technology Beijing | Efficient long-service-life blowing method and system for vanadium extraction-decarburization duplex converters |
-
2022
- 2022-09-30 CN CN202211211935.5A patent/CN115522114B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102352423A (en) * | 2011-10-20 | 2012-02-15 | 攀枝花慧泰金属新材料有限公司 | Method for selecting and smelting titanium from vanadium titanomagnetite at low temperature |
| CN106854702A (en) * | 2015-12-09 | 2017-06-16 | 中国科学院过程工程研究所 | The method that the conversion of one step separates iron, vanadium and titanium in sefstromite concentrate |
| CN106167845A (en) * | 2016-09-27 | 2016-11-30 | 东北大学 | A kind of winding-up CO2or the method for carbon in limestone removing vanadium-bearing hot metal |
| CN108048618A (en) * | 2018-01-29 | 2018-05-18 | 攀钢集团攀枝花钢铁研究院有限公司 | A kind of converter CO2The method of vanadium extraction |
| US20200340070A1 (en) * | 2018-11-07 | 2020-10-29 | University Of Science And Technology Beijing | Efficient long-service-life blowing method and system for vanadium extraction-decarburization duplex converters |
| CN109943719A (en) * | 2019-04-19 | 2019-06-28 | 冉显俊 | The method for preparing titanium slag and pig iron containing vanadium simultaneously as raw material using vanadium titano-magnetite |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115522114B (en) | 2023-09-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110453032B (en) | Method for smelting ultralow manganese steel by using high-manganese molten iron | |
| CN101956044B (en) | Refining method for improving clean class of steel | |
| CN115369211B (en) | Method for enriching nickel by utilizing AOD furnace | |
| CN111020105A (en) | Utilization method of vanadium-containing iron block | |
| CN106319139A (en) | Smelting method for increasing nitrogen content of screw-thread steel | |
| CN115522114B (en) | Method for preparing high-cleanliness medium-high carbon steel liquid in short process | |
| CN115433808A (en) | Method for removing titanium and preserving vanadium from vanadium-titanium-containing molten iron | |
| CN113355477B (en) | Method for realizing high scrap ratio smelting of converter by bottom blowing hydrogen | |
| CN111074037B (en) | Process method for upgrading structure of manganese-rich slag smelting product | |
| CN112853194B (en) | Nitrogen-controllable vanadium alloying method for high manganese steel | |
| CN113025778B (en) | Method for reducing carbon powder consumption in electric furnace oxidation process | |
| CN111304523A (en) | Production process of low-aluminum ferrosilicon | |
| CN111020115A (en) | Method for refining molten steel outside furnace by using liquid blast furnace slag | |
| CN111235352B (en) | Method and system for preparing vanadium-rich slag and low-vanadium alloy from low-vanadium alloy and AOD (argon oxygen decarburization) duplex | |
| CN115466906B (en) | Bearing steel smelting process with low slag content | |
| CN111621686B (en) | Method for producing silicon vanadium nitride by smelting vanadium-rich slag | |
| CN114318015B (en) | Treatment and utilization method of waste vanadium catalyst | |
| SU1157109A1 (en) | Method of melting vanadium-containing alloys | |
| CN113025779A (en) | Method for reducing consumption of auxiliary materials in electric furnace oxidation process | |
| SU1092189A1 (en) | Method for making stainless steel | |
| CN115652023A (en) | Method for producing and processing high-temperature alloy by adopting novel triple-linkage method EBT + VIM + VAR | |
| CN113663816A (en) | Treatment process of tailings obtained by calcium method vanadium extraction | |
| CN116623063A (en) | Pure iron material for lithium iron phosphate battery and preparation method thereof | |
| CN111518983A (en) | Manganese vanadium slag and method for manufacturing manganese vanadium slag by converter | |
| CN113430317A (en) | Method for preparing pig iron, vanadium slag and titanium slag by using submerged arc furnace and smelting furnace |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |