Smelting method of sefstromite

Abstract

The invention provides a smelting method of vanadium-titanium-iron minerals, which comprises the following steps: carrying out reduction roasting on the vanadium-titanium-iron minerals by using a reducing agent to obtain a metallized material; and the metallized material and a slag former are smelted, the slag former comprises sodium salt, and vanadium-containing pig iron and active titanium slag are obtained after smelting is finished. According to the smelting method provided by the invention, a two-step smelting process of pre-reduction and sodium modification smelting is adopted for the vanadium-titanium-iron minerals, so that efficient separation of titanium and iron vanadium is realized, and vanadium-containing pig iron and titanium slag with high additional values are obtained. The titanium slag is high in grade, good in activity and high in acidolysis rate, and the problems that ferrovanadium and the titanium slag are difficult to separate in the vanadium-titanium-iron mineral smelting process, and the titanium slag is poor in activity, low in acidolysis rate and incapable of being economically utilized are solved.

Description

Technical Field

[0001] This invention belongs to the field of mineral smelting technology, and specifically relates to a smelting method for vanadium-titanium iron ore. Background Technology

[0002] Vanadium-titanium magnetite is a strategic mineral resource characterized by the co-occurrence of multiple metals such as iron, vanadium, titanium, and chromium. Vanadium is known as the "MSG of modern industry" and is a key component of high-end alloys and energy storage materials; chromium, as the "king of stainless steel," is irreplaceable in the field of corrosion-resistant alloys; and titanium, due to its lightweight and high-strength properties, is known as the "rising third metal" and "space metal," and is widely used in aerospace and marine engineering.

[0003] Currently, the smelting of vanadium-titanium magnetite is mainly carried out using the traditional blast furnace-converter process. This process is based on the core principle of "extracting iron, storing vanadium, and discarding titanium," which results in a serious waste of resources. After vanadium-titanium magnetite is smelted in a blast furnace, titanium is difficult to recover economically due to the high-temperature reducing environment, leading to a large accumulation of titanium-containing blast furnace slag and high environmental and economic costs.

[0004] The comprehensive utilization of vanadium-titanium magnetite is a global challenge. To address the problems of large solid waste emissions and low resource utilization rates in blast furnace processes, researchers have developed a series of non-blast furnace technologies, typically including direct reduction-electric furnace smelting, direct reduction-grinding, and smelting-reduction processes. Among these, the "direct reduction-electric furnace smelting" process, after extensive research and a 100,000-ton / year pilot demonstration, shows that even at temperatures above 1650℃, efficient separation of titanium slag from molten iron is difficult to achieve. Furthermore, excessively high smelting temperatures lead to stable titanium slag phases, making decomposition and transformation difficult, thus hindering the economic and effective utilization of the titanium slag. The "direct reduction-grinding" process, after thousand-ton-scale pilot tests, found that only when the metallic iron particles grow to a certain size can good separation of iron and vanadium-titanium be achieved, yielding iron powder and vanadium-titanium-containing slag. However, large-scale industrialization remains difficult, and the vanadium-titanium-containing slag cannot be utilized economically and effectively. The HIsmelt and Romelt smelting reduction technologies, according to some literature, have advantages such as strong raw material adaptability, high iron product quality, and suppression of TiC and TiN formation. However, the high TiO2 content and high viscosity of the slag in the smelted titanium slag make slag-iron separation difficult, increase iron loss, and the titanium slag mineral phase is stable, making the titanium extraction process complex and technically challenging, thus not economically viable. For example, CN106854702A discloses a one-step conversion and separation method for iron, vanadium, and titanium in vanadium-titanium iron concentrate. This method involves mixing and roasting the vanadium-titanium iron concentrate with additives and a reducing agent to obtain vanadium-containing pig iron and vanadium-titanium-rich material. The vanadium-titanium-rich material is then leached in water and filtered to obtain a vanadium-containing solution and titanium slag. CN107090533A discloses a high-vanadium pig iron and its preparation method, which involves adding vanadium-titanium magnetite to a carbonaceous reducing agent for smelting. After smelting, low-vanadium molten iron is released, and the slag is then added to a carbonaceous reducing agent and calcium oxide powder for smelting to obtain high-vanadium pig iron.

[0005] Existing roasting or smelting methods for vanadium-titanium ferromagnetic ore, while achieving the separation of vanadium, titanium, and iron, still suffer from limitations in low-grade vanadium-titanium ferromagnetic ore, low activity in the separated titanium slag, and difficulty in economically recovering it. Therefore, a technological breakthrough in the synergistic extraction of multiple metals is urgently needed through process innovation. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a smelting method for vanadium-titanium iron ore, which can achieve efficient smelting and separation of iron, vanadium and titanium for vanadium-titanium iron ore of various grades and improve the activity of titanium slag.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] This invention provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0009] (1) Vanadium-titanium iron ore is reduced and roasted using a reducing agent to obtain metallized material;

[0010] (2) The metallized material is smelted with a slag-forming agent, wherein the slag-forming agent includes sodium salt, and after the smelting is completed, vanadium-containing pig iron and active titanium slag are separated.

[0011] The smelting method provided by this invention adopts a two-step process of pre-reduction-sodium smelting. In the reduction roasting step, vanadium-titanium magnetite is first pre-reduced and roasted. During the pre-reduction process, the iron-containing phase of vanadium-titanium iron ore is reduced to form metallized material, and the metallization rate of the metallized material reaches more than 80%. Then, the metallized material is smelted with a slag-forming agent. The sodium salt slag-forming agent can lower the melting point of high titanium slag and inhibit the formation of Ti(C,N) phase and perovskite. Finally, iron is produced in the form of vanadium-containing pig iron with higher added value, and titanium forms highly active titanium slag. The efficient separation of iron and titanium slag is achieved at a lower temperature, solving the problem that titanium slag cannot be effectively recycled after vanadium-titanium iron ore smelting.

[0012] This invention utilizes a novel sodium-based smelting system to enhance the metallurgical process through chemical means. During the slag-iron separation process, sodium-based slag formation regulates the smelting temperature and titanium slag phase structure, inhibiting the formation of titanium compounds (Ti(C,N)) and perovskite. This achieves efficient separation of titanium slag from molten iron and directional control of the titanium phase at a relatively low smelting temperature (~1400℃). Over 95% of the titanium enters the separated titanium slag, achieving efficient separation of titanium from iron, vanadium, and chromium. Simultaneously, the separated titanium slag exhibits high activity, facilitating subsequent extraction and separation. After upgrading and conversion, the active separated titanium slag can produce active titanium-rich material with extremely high sulfuric acid decomposition activity (acidolysis rate >95%), which can be directly used in the sulfuric acid process for titanium dioxide production. The difference between this method and the one-step addition of reducing agents and sodium salts for smelting lies in the fact that in this method, vanadium and chromium enter the iron phase during smelting, separating from the titanium slag. In contrast, the one-step smelting process separates vanadium, titanium, and chromium slag from iron. The one-step process for vanadium and chromium extraction is relatively long, and there is currently no mature production technology for it.

[0013] Preferably, the vanadium-titanium iron mineral includes any one or a combination of at least two of vanadium-titanium magnetite, vanadium-titanium iron concentrate, chromium-bearing vanadium-titanium magnetite, titanium ore, or titanium slag. Typical but non-limiting combinations include a combination of vanadium-titanium magnetite and vanadium-titanium iron concentrate, a combination of vanadium-titanium iron concentrate and titanium ore, a combination of titanium ore and titanium slag, a combination of vanadium-titanium magnetite, vanadium-titanium iron concentrate, and titanium ore, or a combination of vanadium-titanium magnetite, vanadium-titanium iron concentrate, titanium ore, and titanium slag.

[0014] Preferably, the composition of the vanadium-titanium iron mineral, in mass percentage, includes: TFe 30%-60%, V2O5 0.15%-10.0%, TiO2 4%-55%, and Cr2O3 0%-10%.

[0015] The vanadium-titanium iron mineral contains 30%-60% TFe, for example, 30%, 32%, 34%, 35%, 36%, 38%, 40%, 42%, 44%, 45%, 46%, 48%, 50%, 52%, 54%, 55%, 56%, 58%, or 60%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0016] The V2O5 content in the vanadium-titanium iron mineral is 0.15%-10.0%, for example, it can be 0.15%, 0.5%, 1.0%, 3.0%, 5.0%, 8.0% or 10.0%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0017] The TiO2 content in the vanadium-titanium iron mineral is 4%-55%, for example, it can be 4%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50% or 55%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0018] The Cr2O3 content in the vanadium-titanium iron mineral is 0%-10%, for example, it can be 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0019] Preferably, the reducing agent includes a carbon-based reducing agent and / or a reducing gas.

[0020] Preferably, the carbon-based reducing agent includes any one or a combination of at least two of anthracite, bituminous coal, lignite, semi-coke, biomass, or coke. Typical but non-limiting combinations include combinations of anthracite and bituminous coal, combinations of lignite and coke, combinations of anthracite, bituminous coal, and lignite, combinations of bituminous coal, lignite, and coke, or combinations of anthracite, bituminous coal, lignite, and coke.

[0021] Preferably, the amount of the carbon-based reducing agent is based on the molar ratio of C in the carbon-based reducing agent to Fe in the vanadium-titanium iron mineral of (1-2.5):1, for example, it can be 1:1, 1.2:1, 1.5:1, 1.8:1, 2.0:1, 2.2:1 or 2.5:1, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably (1.2-2.5):1.

[0022] Preferably, the reducing gas includes hydrogen and / or CO.

[0023] Preferably, the amount of reducing gas used is 0.2-2 mg / L based on the mass of the vanadium-titanium iron ore. 3 / kg, for example, could be 0.2m 3 / kg, 0.5m 3 / kg, 0.8m 3 / kg, 1m 3 / kg, 1.2m 3 / kg, 1.5m 3 / kg, 1.8m 3 / kg or 2m 3 / kg, but not limited to the listed values; other unlisted values ​​within the range also apply.

[0024] Preferably, the reduction calcination temperature is 900-1300℃, for example, it can be 900℃, 950℃, 1000℃, 1050℃, 1100℃, 1150℃, 1200℃, 1250℃ or 1300℃, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0025] Preferably, the reduction calcination time is 0.5-4h, for example, it can be 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h or 4h, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0026] Preferably, the metallization rate of the metallized material is ≥80%, for example, it can be 80%, 82%, 85%, 88%, 90% or 95%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0027] In this invention, the metallization rate refers to the percentage of metallic iron content in the metallized material relative to the total iron content.

[0028] Preferably, the smelting method further includes adding a reducing agent in step (2) when the metallization rate of the metallized material is <80%.

[0029] Preferably, the sodium salt comprises any one or a combination of at least two of sodium carbonate, sodium chloride, sodium sulfate, sodium bicarbonate, or sodium borate. Typical but non-limiting combinations include a combination of sodium carbonate and sodium chloride, a combination of sodium sulfate and sodium bicarbonate, a combination of sodium carbonate, sodium chloride, and sodium sulfate, or a combination of sodium sulfate, sodium bicarbonate, and sodium borate.

[0030] Preferably, the amount of sodium salt used is 5-30 wt% of the metallizing material, for example, it can be 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt% or 30 wt%, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0031] Preferably, the melting temperature in step (2) is 1200-1550℃, for example, it can be 1200℃, 1250℃, 1300℃, 1350℃, 1400℃, 1450℃, 1500℃ or 1550℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0032] Preferably, the melting time in step (2) is 0.5-2h, for example, it can be 0.5h, 0.8h, 1h, 1.5h, 1.8h or 2h, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] (1) The smelting method provided by the present invention adopts a two-step smelting process of pre-reduction-sodium melting for vanadium-titanium iron minerals to achieve effective separation of iron, vanadium, chromium and titanium. Finally, the iron is produced as vanadium pig iron with high added value, and the titanium slag has high activity, high titanium dioxide grade, mild acid hydrolysis conditions and high acid hydrolysis rate, which solves the problem that titanium slag cannot be economically utilized after smelting vanadium-titanium iron minerals.

[0035] (2) The smelting method of the present invention has strong applicability to raw materials, especially for the separation of low-grade minerals with TFe content below 50%; compared with the one-step method, the additive utilization rate is high, which can effectively reduce the amount of additives used. Detailed Implementation

[0036] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0037] Example 1

[0038] This embodiment provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0039] (1) Low-iron vanadium-titanium magnetite is reduced and roasted with a reducing agent, wherein the composition of the vanadium-titanium magnetite by mass percentage includes: TFe 42.6%, V2O5 1.51%, TiO2 21.35%, the reducing agent is anthracite, the amount of the reducing agent is based on the molar ratio of C in the reducing agent to Fe in the vanadium-titanium magnetite of 1.6:1, the reduction roasting temperature is 1200℃, the reduction roasting time is 2h, and a metallized material is obtained, the metallization rate of the metallized material is 86%;

[0040] (2) The obtained metallized material is transferred to a melting furnace and smelted with sodium salt slag-forming agent. The sodium salt slag-forming agent is sodium carbonate, the amount of sodium salt slag-forming agent is 10 wt% of the metallized material, the smelting temperature is 1350℃, the smelting time is 2h, and vanadium-containing pig iron and active titanium slag are separated after the smelting is completed.

[0041] Example 2

[0042] This embodiment provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0043] (1) High-speed iron chromium-containing vanadium-titanium magnetite is reduced and roasted with a reducing agent, wherein the composition of the vanadium-titanium magnetite by mass percentage includes: TFe 53.88%, V2O5 0.52%, TiO2 12.19%, Cr2O3 0.69%, the reducing agent is anthracite, the amount of the reducing agent is based on the molar ratio of C in the reducing agent to Fe in the vanadium-titanium magnetite of 1.9:1, the reduction roasting temperature is 1200℃, the reduction roasting time is 2h, and a metallized material is obtained, the metallization rate of the metallized material is 83%;

[0044] (2) The obtained metallized material is transferred to a melting furnace and smelted with sodium salt slag-forming agent. The sodium salt slag-forming agent is sodium carbonate, the amount of sodium salt slag-forming agent is 15 wt% of the metallized material, the smelting temperature is 1400℃, the smelting time is 2h, and vanadium-containing pig iron and active titanium slag are separated after the smelting is completed.

[0045] Example 3

[0046] This embodiment provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0047] (1) The vanadium-titanium magnetite of high-speed rail is reduced and roasted with a reducing agent, wherein the composition of the vanadium-titanium magnetite by mass percentage includes: TFe 58.94%, V2O5 0.48%, TiO2 10.87%, the reducing agent is anthracite, the amount of the reducing agent is based on the molar ratio of C in the reducing agent to Fe in the vanadium-titanium magnetite of 1.3:1, the reduction roasting temperature is 1200℃, the reduction roasting time is 1.5h, and a metallized material is obtained, the metallization rate of the metallized material is 82%;

[0048] (2) The obtained metallized material is transferred to a melting furnace and smelted with sodium salt slag-forming agent. The sodium salt slag-forming agent is sodium carbonate, the amount of sodium salt slag-forming agent is 15 wt% of the metallized material, the smelting temperature is 1400℃, the smelting time is 2h, and vanadium-containing pig iron and active titanium slag are separated after the smelting is completed.

[0049] Example 4

[0050] This embodiment provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0051] (1) Low-iron vanadium-titanium magnetite is reduced and roasted with a reducing agent, wherein the composition of the vanadium-titanium magnetite, by mass percentage, includes: TFe 42.6%, V2O5 1.51%, TiO2 21.35%, the reducing agent is anthracite, the amount of the reducing agent is based on the molar ratio of C in the reducing agent to Fe in the vanadium-titanium magnetite of 1.2:1, the reduction roasting temperature is 1300℃, the reduction roasting time is 1h, and a metallized material is obtained, the metallization rate of the metallized material is 80%;

[0052] (2) The obtained metallized material is transferred to a melting furnace and smelted with sodium salt slag-forming agent. The sodium salt slag-forming agent is sodium carbonate, the amount of sodium salt slag-forming agent is 30 wt% of the metallized material, the smelting temperature is 1250℃, the smelting time is 1h, and after the smelting is completed, vanadium-containing pig iron and active titanium slag are separated.

[0053] Example 5

[0054] This embodiment provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0055] (1) The low-iron vanadium-titanium magnetite is ground, pelletized, and then placed in a gas-reducing vertical shaft furnace for reduction roasting. The composition of the vanadium-titanium magnetite, by mass percentage, includes: TFe 42.6%, V2O5 1.51%, and TiO2 21.35%. The reducing agent is H2 and CO, with a volume ratio of H2 to CO of 2:1. The total amount of H2 and CO used is 1.5 mg / L based on the mass of the vanadium-titanium magnetite. 3 / kg, the reduction roasting temperature is 900℃, the reduction roasting time is 4h, and a metallized material is obtained, the metallization rate of the metallized material is 85%;

[0056] (2) The obtained metallized material is transferred to a melting furnace and smelted with sodium salt slag-forming agent. The sodium salt slag-forming agent is sodium carbonate, and the amount of sodium salt slag-forming agent is 5 wt% of the metallized material. The smelting temperature is 1550℃ and the smelting time is 0.5h. After the smelting is completed, vanadium-containing pig iron and active titanium slag are separated.

[0057] Example 6

[0058] This embodiment provides a smelting method for vanadium-titanium iron ore. Compared with Example 1, the reduction roasting temperature in step (1) is controlled at 850°C, and the rest is the same as in Example 1.

[0059] Example 7

[0060] This embodiment provides a smelting method for vanadium-titanium iron ore. Compared with Example 1, the reduction roasting temperature in step (1) is 1400℃, and the rest are the same as in Example 1.

[0061] Comparative Example 1

[0062] This comparative example provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0063] (1) Low-iron vanadium-titanium magnetite is roasted, wherein the composition of the vanadium-titanium magnetite by mass percentage includes: TFe 42.6%, V2O5 1.51%, TiO2 21.35%, the roasting temperature is 1200℃, and the roasting time is 1h, to obtain roasted material;

[0064] (2) The obtained roasted material is transferred to a melting furnace and smelted with sodium salt slagging agent. The sodium salt slagging agent is sodium carbonate, the amount of sodium salt slagging agent is 10 wt% of the metallized material, the smelting temperature is 1350℃, and the smelting time is 2h.

[0065] That is, compared with Example 1, no reducing agent is added in step (1), and the rest is the same as Example 1.

[0066] Comparative Example 2

[0067] This comparative example provides a method for smelting vanadium-titanium iron ore, the smelting method comprising the following steps:

[0068] Low-iron vanadium-titanium magnetite, a reducing agent, and a sodium salt slagging agent are added to a melting furnace for smelting. The vanadium-titanium magnetite comprises, by mass percentage, 42.6% TFe, 1.51% V2O5, and 21.35% TiO2. The reducing agent is anthracite, and the amount of reducing agent is based on a molar ratio of C in the reducing agent to Fe in the vanadium-titanium magnetite of 1.6:1. The sodium salt slagging agent is sodium carbonate, and the amount of sodium salt slagging agent is 10 wt% of the metallized material. The smelting temperature is 1350℃, and the smelting time is 2 hours.

[0069] Comparative Example 3

[0070] This comparative example provides a smelting method for vanadium-titanium iron ore. Compared with Example 1, sodium carbonate in step (2) is replaced with calcium chloride by an equal mass, and the rest is the same as in Example 1.

[0071] Performance testing

[0072] The vanadium-containing pig iron and titanium slag obtained from the examples and comparative examples were analyzed for composition, and the results are shown in Table 1.

[0073] The titanium slag obtained in the examples and comparative examples was subjected to acid hydrolysis activity test. The specific steps are as follows: After grinding the titanium slag, it was mixed with sulfuric acid with a mass concentration of 60% at a solid-liquid mass ratio of 1:2, heated to ~60℃ for acid hydrolysis reaction, filtered after acid hydrolysis to obtain titanium solution, the concentration of titanium solution was measured and the acid hydrolysis rate of titanium slag was calculated. The results are shown in Table 1.

[0074] Table 1

[0075]

[0076] In the table, " / " indicates no data.

[0077] As shown in Table 1, the smelting method provided by this invention can effectively smelt and separate vanadium-titanium iron ore, achieving the separation of vanadium iron and titanium, producing vanadium-containing pig iron, and obtaining highly active titanium slag. The vanadium-containing pig iron has high Fe and V content. For chromium-containing vanadium-titanium iron ore, both vanadium and chromium enter the iron phase, forming vanadium-chromium pig iron. The active titanium slag has a high TiO2 grade and high activity, and acidolysis can be completed under low concentration (60%) sulfuric acid and low temperature (60℃) conditions, with an acidolysis rate exceeding 95%. Compared to Example 1, in Example 6, when the reduction roasting temperature is too low, the mineral metallization is incomplete, with a metallization rate of only 43%, resulting in lower vanadium separation and decreased titanium slag activity. In Example 7, when the reduction roasting temperature is too high, the metallization rate improvement is not significant, reaching 85%, but excessively high temperatures lead to high energy consumption, and the iron particles in the material are in a sintered state, making subsequent crushing and melting difficult, thus resulting in decreased product activity. In Comparative Example 1, roasting without adding a reducing agent prevented the minerals from being reduced and metallized, and even oxidation occurred. Subsequent melting processes were also impossible, resulting in no vanadium-containing pig iron or active titanium slag. In Comparative Example 2, a one-step method was used; at this temperature, the material remained in a sintered state, making melting impossible. In Comparative Example 3, a calcium-based slagging agent was used; similarly, melting was not achieved at this temperature. Calcium-based slagging agents require high melting temperatures, exceeding 1550℃. Excessively high melting temperatures also reduce the activity of the titanium slag. Therefore, sodium-based slagging agents can effectively lower the melting temperature and improve the activity of the titanium slag.

[0078] In summary, the smelting method provided by this invention employs a two-step smelting process of pre-reduction-sodium smelting for vanadium-titanium iron ore, achieving efficient separation of titanium and vanadium iron, and obtaining high-value-added vanadium-containing pig iron and titanium slag. The titanium slag has high grade, good activity, and high acid hydrolysis rate, solving the problems of difficulty in separating vanadium iron and titanium slag during the smelting process of vanadium-titanium iron ore, as well as the poor activity and low acid hydrolysis rate of titanium slag, making it uneconomical to utilize.

[0079] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for smelting vanadium-titanium iron ore, characterized in that, The smelting method includes the following steps: (1) Vanadium-titanium iron ore is reduced and roasted using a reducing agent to obtain metallized material; (2) The metallized material is smelted with a slag-forming agent, wherein the slag-forming agent includes sodium salt, and after the smelting is completed, vanadium-containing pig iron and active titanium slag are separated.

2. The smelting method according to claim 1, characterized in that, The vanadium-titanium iron minerals include any one or a combination of at least two of the following: vanadium-titanium magnetite, vanadium-titanium iron concentrate, chromium-bearing vanadium-titanium magnetite, titanium ore, or titanium slag. Preferably, the composition of the vanadium-titanium iron mineral, in mass percentage, includes: TFe 30%-60%, V2O5 0.15%-10.0%, TiO2 4%-55%, and Cr2O3 0%-10%.

3. The smelting method according to claim 1 or 2, characterized in that, The reducing agent includes carbon-based reducing agents and / or reducing gases.

4. The smelting method according to claim 3, characterized in that, The carbon-based reducing agent includes any one or a combination of at least two of anthracite, bituminous coal, lignite, semi-coke, biomass, or coke. Preferably, the amount of the carbon-based reducing agent is such that the molar ratio of C in the carbon-based reducing agent to Fe in the vanadium-titanium iron mineral is (1-2.5):1; Preferably, the reducing gas includes hydrogen and / or CO; Preferably, the amount of reducing gas used is 0.2-2 mg / L based on the mass of the vanadium-titanium iron ore. 3 / kg.

5. The smelting method according to any one of claims 1-4, characterized in that, The reduction calcination temperature is 900-1300℃.

6. The smelting method according to any one of claims 1-5, characterized in that, The reduction calcination time is 0.5-4 hours.

7. The smelting method according to any one of claims 1-6, characterized in that, The metallization rate of the metallized material is ≥80%; Preferably, the smelting method further includes adding a reducing agent in step (2) when the metallization rate of the metallized material is <80%.

8. The smelting method according to any one of claims 1-7, characterized in that, The sodium salt includes any one or a combination of at least two of sodium carbonate, sodium chloride, sodium sulfate, sodium bicarbonate, or sodium borate; Preferably, the amount of sodium salt used is 5-30 wt% of the metallizing material.

9. The smelting method according to any one of claims 1-8, characterized in that, The melting temperature is 1200-1550℃.

10. The smelting method according to any one of claims 1-9, characterized in that, The smelting time is 0.5-2 hours.

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